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lynnl
03-27-2012, 11:49 PM
My JD mower, for quite awhile now, has been very erratic at starting.
Sometimes the starter will activate, but more often it will not. Yet after a long wait it will sometimes start.

I found a tip on the internet, recommending puting a relay in the circuit. The explanation being that the circuit doesn't have enough oomph to drive the solenoid and/or starter. So I did that, and it worked last time. But today - the same old problem.

Pulled the starter and solenoid off, applied power to the starter directly at the output lug on the solenoid, and the starter shaft spins ok, but the pinion does NOT pop up. Should it? ...if I'm bypassing the solenoid circuit?

Is there something in the solenoid circuitry that makes the pinion pop up, independently of the main power to the starter shaft?

Black_Moons
03-28-2012, 12:25 AM
Afaik, Most starters use helix grooves between the gear and starter shaft to make the pinion gear pop up. Maybe it needs a nice oil massage to free it up?

oldtiffie
03-28-2012, 12:32 AM
Maybe it needs a new battery with enough starting capacity or else the charging circuit needs checking out.

winchman
03-28-2012, 12:36 AM
If the starter doesn't have a fork to move the pinion, the pinion will slide on a spiral spline. The inertia of the pinion causes it to move toward the engaged position when the motor starts turning. Once it touches the flywheel gear, the torque on the spiral spline forces the pinion into complete engagement.

oldtiffie
03-28-2012, 12:55 AM
I had a similar problem with my "Toro" and "Simplicity" RO mowers on occassion. Both had singlem cylinder B&S engines. I just "jump started" it with a good fully charged battery to get the job done and until I could check it out. It was almost always a poor (just about buggered) battery on the mower. A trip to the mower shop for a new battery and I was on my way. Both of those machines had lead-acid batteries.

I now have a "zero turn" "Husquana" (sp?) mower (a great machine) that has a "gel" battery (to turn over a 19HP B&S single cylinder OHV motor). Never a problem.

jnissen
03-28-2012, 01:12 AM
Yep. Mower batteries are worthless lately. If I get a year out of mine they are doing well. Tried a larger GelCell and that worked a bit better but still no more than two years max. I figured it's the poor charge circuit in BS engines and the fact I only run the thing once every couple of weeks in the summer and once a month over the winter. May try a trickle charger to see if that helps.

Boostinjdm
03-28-2012, 01:16 AM
Clean connections and a good battery are a must. If you really have to crank it to start and then don't spend much time mowing, the charging system can't get the battery back up to full charge.

SteveF
03-28-2012, 03:21 AM
I have a Battery Minder that I use on my various pieces of machinery to keep the batteries up to full charge. Works well. Supposedly increases the life of the batteries but without doing a side by side test I can't vouch for that claim.

Steve

Weston Bye
03-28-2012, 08:08 AM
I must be living on borrowed time.

I'm going on my fourth season on the OEM battery in my Snapper with a B&S engine. When I got the mower, the dealer told me to bring the battery indoors for the winters. I did, and gave it an occasional topping-up charge; usually a half-hour or less on a trickle charger was enough.

But nothing lasts forever...

JCHannum
03-28-2012, 08:19 AM
Low battery could be a problem, but the pinion gear should be free enough to move out even with a sluggish battery on the bench. Give it a drink of penetrating oil on the spiral grooves and make sure it is free to move. It should move with little effort and no restrictions.

After that go for battery and connections. The internal contacts of the solenoid eventually wear and get pitted and starters can get dead spots on the commutator. These are lasts stop after the cheaper fixes have failed.

lynnl
03-28-2012, 08:40 AM
The battery is not the issue. It's relatively new and fully charged; also I've tried starting with a battery charger hooked up, in "Boost" or "Start" mode - makes no difference, I'll still get only the "click" response.

As I said, it will sporadically work, and on those occasions the starter spins up with plenty of power.

I can't see any helix or splines inside. What's the insides of a starter and a solenoid like? If I take it apart, are there things that go "sproin-nnng", or difficult to put back together?

lynnl
03-28-2012, 08:45 AM
.....
The inertia of the pinion causes it to move toward the engaged position when the motor starts turning. Once it touches the flywheel gear, the torque on the spiral spline forces the pinion into complete engagement.

Is that to say that since I've removed it from the mower and it can no longer touch the flywheel gear, I should not expect the pinion to move very much?

GKman
03-28-2012, 09:02 AM
On mine there is just really coarse threads on the gear and shaft. The gear is just a loose fitting nut on the shaft. I can manually twist the gear on the shaft and it will raise up. Hope this explains what we're talking about. I've been through the same process and found a fresh battery as the solution. I use a $30 charger/maintainer (Battery Tender) all winter and get 4 - 6 years where I used to get 1 or 2.

Black_Moons
03-28-2012, 09:37 AM
The battery is not the issue. It's relatively new and fully charged; also I've tried starting with a battery charger hooked up, in "Boost" or "Start" mode - makes no difference, I'll still get only the "click" response.

As I said, it will sporadically work, and on those occasions the starter spins up with plenty of power.

I can't see any helix or splines inside. What's the insides of a starter and a solenoid like? If I take it apart, are there things that go "sproin-nnng", or difficult to put back together?

Does the starter make any noise when it 'does not work'?

If the starter makes no sound other then the solenoid clicking, its something stopping the starter from turning (Low battery, Brushes, etc)

If the starter sounds like it spins up and down, then its the pinion not extending (Rust? Debris?)

lynnl
03-28-2012, 09:51 AM
On the side of the starter that faces the engine when installed, there's a little hole. I stuck a screwdriver in that hole and engaged a small slot in the bottom of the pinion, and I could pry the pinion upward. I could feel a spring tension resisting the upward motion.

The motion appeared to be straight up, not spiraling.

I'd kinda like to tear into both starter and solenoid, but I don't know what problems to expect, since I don't know how the innards work.

Bob Ford
03-28-2012, 09:56 AM
The starter solenoid contacts can form a oxide that does not conduct well. Quick and dirty check, connect the starter direct to battery. If it works like it should then the solenoid is bad. Most are a sealed unit and cost less then $10.

Bob

garagemark
03-28-2012, 09:59 AM
I have had several stater solenoids go bad. The contacts in them apparently got cruddy or burnt. They would read good with a multimeter but they would not carry enough current to run the motor. So even if it "clicks", it might not be sending enough current to the motor.

If you have a DC amp clamp you can see how much current is being sent to the motor. That lone test should narrow the problem down significantly.

Mark

JCHannum
03-28-2012, 10:34 AM
Do any of you youngsters know how to jump a solenoid with a pair of pliers? It was the standard fix for a bad solenoid back in the days.

Just put one (uninsulated) handle on the battery cable terminal on one side of the solenoid and the other on the other side. If the starter works, the solenoid is bad. From the later description, it does sound like the solenoid. I would also remove the relay that has been added. It serves no purpose but to confuse the situation.

Black_Moons
03-28-2012, 10:44 AM
Having someone hold a DMM in voltage mode to various points while you crank it can also tell you a lot.

Voltage at battery drops below 8v or so: Dead battery
Voltage at solenoid drops: Bad connections
Voltage at starter drops: Bad solenoid (or connections

Steve Steven
03-28-2012, 11:13 AM
Lynnl,
What engine do you have? I have a JD SRX95 with the Kawaski engine, my son who used to work for John Deer dealer for many years (now works for Toro Dealer!) told me the problem with that engine was with the starter circuit, it needed a "relay" which sounded to me like a capacitor from how he described it. He wasn't sure what it was or how it worked, but sounds like you found the same internet thing he knew about. He said the problems with the Kawasaki engine were well known.

Steve

RWL
03-28-2012, 11:14 AM
I have a Battery Minder that I use on my various pieces of machinery to keep the batteries up to full charge. Works well. Supposedly increases the life of the batteries but without doing a side by side test I can't vouch for that claim.

Steve

I've had a BatteryMinder on mine for several years. I got somewhere between 5 and 7 years on the OEM battery on my Grasshopper zero turn, and about 7-9 years on the auto battery that starts my Gravely. They stay connected to the trickle charger between uses. It makes a difference. With the BatteryMinder brand of charger I have not noticed any decrease in the water level in the cells.

JCHannum
03-28-2012, 11:22 AM
Without a model number for the mower or a photo of the actual starter/solenoid/Bendix involved, any suggestions beyond making sure the battery is fully charged are just guessing.

It could be anywhere in the system, including a the ignition switch or a safety switch making intermittent contact.

lakeside53
03-28-2012, 11:34 AM
I've had a BatteryMinder on mine for several years. I got somewhere between 5 and 7 years on the OEM battery on my Grasshopper zero turn, and about 7-9 years on the auto battery that starts my Gravely. They stay connected to the trickle charger between uses. It makes a difference. With the BatteryMinder brand of charger I have not noticed any decrease in the water level in the cells.


Yes, I get the same on my generators and other equipment. Before I was lucky to get 4 years. I use the small 3 stage chargers sold for boats.

lynnl
03-28-2012, 12:00 PM
Do any of you youngsters know how to jump a solenoid with a pair of pliers? It was the standard fix for a bad solenoid back in the days.

Just put one (uninsulated) handle on the battery cable terminal on one side of the solenoid and the other on the other side. If the starter works, the solenoid is bad. From the later description, it does sound like the solenoid. I would also remove the relay that has been added. It serves no purpose but to confuse the situation.

Right now the relay is disconnected. At one point yesterday, with it connected in the circuit, the starter was operating, but there was something that didn't seem right. It seemed there was voltage or forces opposing the starting effort. Kind of hard to explain. But it did blow a 15A fuse mounted on the back of the little switch circuit board/module. (Which I've replaced.)

A week or so ago when I was having problems, I installed the relay. Still no workee. So then I pulled out the switch module mounted on the console, and gave it a good cleaning/brushing to remove lots of dust and crud. Put it back in and the it started fine (without the relay). So hooked the relay back up just to test, and again it started. So I decided the cleaning solved the problems, and the relay wasn't needed, so I de-installed it. Mower worked fine that day.

This is the Kawasaki 14HP engine, LX176 mower.

I just opened up the starter. Everything looks pretty good. But sure enough, "sproin-nng" ...forgot about the brush springs. Luckily I didn't lose any. (YET!) :D Now the hassle of getting them back in.

Dropped a few drops of oil on the rotor shaft helices the pinion rides on. It's lifted by a plastic fork actuated by the solenoid.

Does the wire from the ignition switch to the solenoid carry 12V? Can I just touch a 12V wire straight from battery to that solenoid terminal to test it? (I'm not talking about the main heavy duty connection from battery to solenoid, but the smaller one.)

I hope the problem is NOT some stray, miscellaneous safety interrupt wire. There're wires running everywhere, and they're faded and crudded up so much, tracking that down will be a nightmare.

Jim, I'd thought about trying to "jump" past the solenoid, like you describe, but am a little leary. Will that "Zap" me, if I'm not touching the grounding system anywhere? We used to play with old hand cranked phone generators as kids, just to get shocked. But I'm older and wiser (i.e. more scared) now. :D

(added) Incidentally, this problem has been present for at least 3 or 4 years, maybe longer, at first just once in a blue moon. But it has gotten progressivelly worse the past couple of years.

My battery connections all look good ...no corrosion to speak of.

JCHannum
03-28-2012, 12:28 PM
You are only dealing with 12 volts, no Zap, things might get hot though, but it is usually gradual.

The progressive nature is more indicative of a switch in the circuit, ignition, safety, or the solenoid itself.

Wiring diagram;

http://ww2.justanswer.com/uploads/motoforge/2010-10-05_194625_JohnDeereLX-176WiringDiagram.jpg

lynnl
03-28-2012, 01:05 PM
Wiring diagram;

http://ww2.justanswer.com/uploads/motoforge/2010-10-05_194625_JohnDeereLX-176WiringDiagram.jpg

Ohmygosh! Looking at a schematic, I'm much like a hog looking at a wristwatch. :D

I got the starter back together. Tried to tear into the solenoid, but the plunger that engages the fork that manipulates the pinion doesn't want to release. I guess that needs to be done with the starter rotor free to move enough for clearance.

As I see it, even jumping across from the solenoid/battery terminal to the starter terminal will still leave that fork unactuated, so that the pinion will still not pop up to engage the flywheel.

I need to make sure that solenoid plunger is working. The audible 'click' would seem to suggest it is. As I understand the workings: when the switch sends a voltage to the solenoid, that energizes the coil which sucks down a plunger, which both lifts the pinion (via the fork) and simultaneously closes the circuit between battery and starter.

So, just touching that solenoid terminal w/12v should make the pinion pop up, ...right?

I do have a multimeter, but nobody's here to help me operate the switch whilst holding the meter leads. So it gets a little tricky with only two hands and two feet..

Oh, I do greatly appreciate the help Jim, and everybody!!! A lot!

Black_Moons
03-28-2012, 03:04 PM
I do have a multimeter, but nobody's here to help me operate the switch whilst holding the meter leads. So it gets a little tricky with only two hands and two feet..

Oh, I do greatly appreciate the help Jim, and everybody!!! A lot!

Find some tiny jumper clip leads then.

Bob Fisher
03-28-2012, 03:51 PM
For sure, lube the pinion,it should spin right out on the bench. The inertia of the pinion is plenty unless there is too much friction. I use a cheap HF float charger on my garden tractor and got 10 yrs on the original battery supplied by John Deere, hope the aftermarket batteries do as well. Bob.

lynnl
03-28-2012, 04:12 PM
Well I got the grass mowed.
I was able to jump start as Jim suggested, by connecting a jumper cable from battery to starter terminal, while simultaneously key starting at the switch.

It appears the solenoid operates the pinion just fine, but evidently isn't making a good circuit to the starter terminal.

Before putting it back on the mower I checked for continuity between the battery and starter lugs, while lifting the pinion with a screwdriver. Got no continuity. Of course I wasn't sure that would deflect the solenoid internals enough to close the circuit.

After mowing and then shutting it off, it would start ok just with the switch.

I may just hook a short pigtail on that starter lug, so it'll be easier to jump start, and use it that way.

I would just get a new mower, but this one has a 38" deck, which just fits through my gate between rear and front yards. All I the new ones I see nowadays have too big of a deck to fit. I do have a larger double gate, but that's a pain in the rear to open and close just for mowing. Also, other than the plastic hood is too broken up to use, this mower runs and mows just fine.

JCHannum
03-28-2012, 04:34 PM
It may be a safety switch then, you might try jumping them out. Probably three of them, seat, neutral and blades. The seat & neutral are most likely candidates.

lynnl
03-28-2012, 05:09 PM
I overrode the seat switch years ago, right after I got the mower.

I don't understand how safety interrupts could be a factor, since there's only one wire going to the solenoid (from the switch I presume), and I am getting the 'clicking' at the solenoid even when it doesn't start.
...I'm not arguing, I'm just not understanding.

Would the solenoid likely be sensitive to different voltages, which might vary depending on what those interrupts or lockouts are sending?

I'll go try to start it with the blades engaged, and see what the response is.

JCHannum
03-28-2012, 08:03 PM
The clicking at the solenoid is a symptom of a bad solenoid. It is pulling in, but not making contact. This, of course, assuming a good battery.

lynnl
03-28-2012, 08:39 PM
A while ago I engaged the blade control, then tried to start. No clicking, or any response at all. I then disengaged the blade control and when I turned the key the starter activated.

I'm now of the same opinion, Jim. I think it's a weak or malfunctioning solenoid. If I can assure myself I can replace it without too much trouble, I will do so. A web search suggests about $25 or so for a new one, so that's not too bad. I'll gladly pay that to avoid one day's worth of hassle and frustration.

Dealing with those brush springs is the only significant issue with disassembling the starter, and now I've learned to put a strip of tape over each one to keep them from popping out.

Thanks again for your assistance!

J. Randall
03-28-2012, 09:42 PM
Lynnl, this sentence, My battery connections all look good ...no corrosion to speak of., leads me to think you just looked at them and did not clean them. You can not tell by looking, and that is the first thing you should have done, was cleaned both battery posts and terminal ends, including where the ground cable bolts on to the frame. If that has not been done, there is a good chance that is where the problem lies.
James

oldtiffie
03-28-2012, 09:52 PM
A while ago I engaged the blade control, then tried to start. No clicking, or any response at all. I then disengaged the blade control and when I turned the key the starter activated.

..................................................



That is one of the safety interlock devices that are mandatory probably in the USA and certainly here and European Union and all are there to prevent you starting the engine or the mower unless you are seated, and have the blade control inactivated, the brake on and the gear-box in neutral. There are others.

Manufacturers have to have all safety/interlocks required of all juristictions where they intend to sell their product, so they include all interlocks to cover all bases.

Highpower
03-29-2012, 06:12 AM
The clicking at the solenoid is a symptom of a bad solenoid. It is pulling in, but not making contact. This, of course, assuming a good battery.

Yep. The plunger in the solenoid is supposed to make a connection between two copper plates inside the solenoid when the plunger pulls in. One or both of the the copper terminals are eroded away from arcing, and preventing battery voltage getting to the main starter power terminal.

You might be able to take the solenoid apart and clean up the copper plates a bit (if there is enough of them left) to get it to work a while longer. But for the cost of a new solenoid.... :rolleyes:

http://www.ebay.com/itm/STARTER-SOLENOID-John-Deere-Tractor-LX176-LX178-LX188-/230672752932?hash=item35b52ae124&vxp=mtr

JCHannum
03-29-2012, 07:38 AM
If it is like the GM solenoids, you can take it apart and turn the battery cable bolt 180 and use the other half for a few more years.

sasquatch
03-29-2012, 08:54 AM
Jim beat me to it, about turning the copper lug around, done that a few times over the years, and it will work again for years.

Also as posted above, ALL cable connections , including the ground on the frame should be the #1 thing cleaned first.

lynnl
03-29-2012, 12:19 PM
I like the idea of flipping the ends of the contacts in the solenoid. That sounds more thrilling and exciting than just buying a new one.

Does anyone know just how the solenoid comes apart? (It's a Nippondenso)
...or have any good ideas? I haven't been able to find any good instructions with google.

When I tried to pull the solenoid out of the upper casting that houses both the starter and solenoid, it would only drop down an inch or so. The upper end of the plunger is somehow engaged with the fork that extends through the casting and engages the pinion in the starter.

That was after I had already buttoned the starter back together. But..., when I had tried to pull the starter rotor down out of that casting, it would not come all the way, since it too was held by that fork.

It's kind of a chicken and egg situation. Don't know whether I should attack the chicken or the egg. :)

lynnl
03-29-2012, 05:07 PM
I like the idea of flipping the ends of the contacts in the solenoid. That sounds more thrilling and exciting than just buying a new one.



Well, scratch that idea. The solenoid is a sealed unit.

I suppose I could try to bend out the crimping, to pull out the bottom end. But to save $25 it's hardly worth the effort; plus, there may be other internal issues.

Called the local J.D. place and was quoted $81 and change! I would've paid more to get it locally. But more than TRIPLE? I think not.

Black_Moons
03-29-2012, 05:26 PM
Well, scratch that idea. The solenoid is a sealed unit.

I suppose I could try to bend out the crimping, to pull out the bottom end. But to save $25 it's hardly worth the effort; plus, there may be other internal issues.

Called the local J.D. place and was quoted $81 and change! I would've paid more to get it locally. But more than TRIPLE? I think not.


Yea I hate local places trying to rip me off. Yes I know you have overhead. Yes I know your part might last longer and have an easier to use warranty. No, Its NOT WORTH THAT MUCH!

Local computer stores want $40 for 1 gig of DDR3 1333 ram. 4gig of DDR3 1333 ram online is $25. I laughed in the salesman's face when he told me the price and told him to update his prices from 5 years ago to todays price, And that 1gig of ram online costs about $7~10 now apparently.

http://www.londondrugs.com/Cultures/en-US/Products/Computers.htm?BreadCrumbs=Computers;Computers;Memo ry;Computer Memory&Sort=0&Page=1
Compaired to: http://www.pricewatch.com/system_memory/

Cheapest ram they have: DDR3 2gig 1066 $30
Equivalent DDR3 1333 ram: $8.50

They have a stick of DDR400 1gig for $70. hahahahha. Need to move the decimal over buddy.

Willy
03-29-2012, 05:44 PM
Well, scratch that idea. The solenoid is a sealed unit.

I suppose I could try to bend out the crimping, to pull out the bottom end. But to save $25 it's hardly worth the effort; plus, there may be other internal issues.

Called the local J.D. place and was quoted $81 and change! I would've paid more to get it locally. But more than TRIPLE? I think not.

I'm not selling these:D , but if it's anything like this, a local automotive electrical shop should have something similar for roughly the same price.
They should not be anywhere near $81 unless you like collecting purty little green and yellow boxes.

http://www.amazon.com/Starter-Solenoid-Terminal-Intermittent-Replacement/dp/B0050PQIUG

Beazld
03-29-2012, 07:15 PM
I chased a similar problem on a 10 year old Cub Cadet with a Kohler 14 hp engine. Liked to drive me crazy. Finally found that the ground wire from the battery to the frame was not making good contact on the frame. Simple to fix after replacing the battery, starter and pulling out what little hair I had left.

lynnl
03-30-2012, 11:58 AM
Simple to fix after replacing the battery, starter and pulling out what little hair I had left.

Yeah, I'm getting a little thin on top too. :)

I ordered a new solenoid. It that doesn't work at least I will have eliminated that. All of my battery connections are good. I always coat them with a gel or goop made for that purpose. The cable terminals, I've scraped to a clean, bright coppery color.

Most of the other misc wiring is sheathed in a wiring harness. Of course there are numerous wire ends that are exposed to dust and grit and crud. I'm keeping my fingers crossed, in hopes that's not where the problem lies.

It's maddening! Back when I was wearing a younger man's clothes, all problems were clear cut and always solvable with a direct, orderly approach. I always looked forward to tackling the problems that arose. Nowadays they're just simply a bothersome pain in the a$$, and invariably arise at the worst possible time.

Life is hell! ...and then you die. :D

Back in the '70s I had a VW bug. One day at work, after driving it for a year or so, I started it up to go to lunch, and it died in the parking lot after going about 30 feet. A friend opined that it was a bad condenser, so he brought me a new one when he returned from lunch. We replaced the condenser and it worked fine. ...for a few months.

Over the next couple of years I acquired a whole glovebox full of condensers as a result of this thing's aperiodic failure while driving. Finally I discovered that putting an old condenser back in worked just as well.

After that discovery I spent the next 2 or 3 years rebuilding the carburetor (2 or 3 times), new wires, new distributor, fiddling with this and that, putting clothespins on the fuel lines (vapor lock voodoo) , and anything else I could think of. I'd always get it running again, and eventually the problem did seem to end ...at least for my remaining ownership. But to this day I don't know what the actual problem was.

But, since I was younger and more foolish then, that experience didn't seem as vexing to me, as I know it would now.

...or maybe I'm more foolish now. It's hard to know just what is the correct reference frame. :D

Jim Caudill
04-03-2012, 12:12 AM
This is a well known issue - as well as the solution is well known. There are so many safety switches in the starter circuit, that an excessive voltage drop occurs between the battery and the starter solenoid. The relay that is "added" is wired so that the original starting lead actuates the relay and not the solenoid. You create a very direct path from the battery terminal thru the relay contacts to the solenoid. The relay will tolerate a significant voltage drop and still actuate. When it closes, there will be a direct path from the battery to the starter solenoid. If you have an electric PTO switch, I have found that to be an area for a large part of the total voltage drop. The PTO switch must be in the "off" position to allow the starting voltage to pass thru. For several years, I have used a screwdriver to bridge between the blade terminal on the solenoid and the main battery cable connection. This essentially is what the relay modification does. You can buy the John Deere kit with a plug&play harness and schematic, or you can buy the relay at most "Big Box" stores for around $12 and make up your own harness.

lynnl
04-03-2012, 05:30 PM
Jim, I ran across that explanation on the internet last fall, and it makes sense. I found and downloaded a schematic and instructions for hooking up the relay, and bought one and wired it up.

After I got the relay ready but not yet installed, I cleaned all the crud from the switch circuit board and then I tried the starter without the relay. It started. So I then hooked up the relay circuit and it again started. (Wanted to make sure I had the relay circuit correct.) So I sez to myself, "self, cleaning the switch must've done the trick, no need for the relay."

Well the next time I tried to start it up, it again would not energize the starter. So I put the relay back in the circuit, thinking "Aha, this'll fix it." But it still would not energize the starter.

I just today received a new solenoid I ordered last week. But haven't yet installed it.

J. Randall
04-03-2012, 07:30 PM
Seems to me that if the solenoid is good and all connections are good, that another relay in the circuit to try and do the job the solenoid is designed to do, is just redundant.
James

Jim Caudill
04-03-2012, 07:49 PM
J. Randall, the issue is that the starter solenoid needs damn near 12v to actuate, otherwise it just clicks. That extra relay will actuate as low as 10volts or so. Bottom line is that the relay can tolerate the voltage drop caused by so many damned safety switches and connectors and contacts. The starter solenoid cannot.

J. Randall
04-03-2012, 11:48 PM
J. Randall, the issue is that the starter solenoid needs damn near 12v to actuate, otherwise it just clicks. That extra relay will actuate as low as 10volts or so. Bottom line is that the relay can tolerate the voltage drop caused by so many damned safety switches and connectors and contacts. The starter solenoid cannot.

Jim I understand the principle of what you are saying, just hard for me to visualize that being the sole problem when there are a multitude of other brands on the market with all those switches that don't have that problem. Just to satisfy my own curiousity I am almost tempted to google some schematics and compare them.
James

Bob Ford
04-03-2012, 11:59 PM
James,

The relay that is added draws maybe .1 amp. The solenoid draws about 3 amps. All the safety switches in series can likely only pass 3 amps when new. Dirt moisture and age lowers the rating.The added relay's contact gets power direct from the battery then passes this to the solenoid.
You could load test each safety switch and replace the bad ones or use a relay until that does not work. Then replace the bad switches.

Bob

hardtail
04-04-2012, 12:11 AM
This is a well known issue - as well as the solution is well known. There are so many safety switches in the starter circuit, that an excessive voltage drop occurs between the battery and the starter solenoid. The relay that is "added" is wired so that the original starting lead actuates the relay and not the solenoid. You create a very direct path from the battery terminal thru the relay contacts to the solenoid. The relay will tolerate a significant voltage drop and still actuate. When it closes, there will be a direct path from the battery to the starter solenoid. If you have an electric PTO switch, I have found that to be an area for a large part of the total voltage drop. The PTO switch must be in the "off" position to allow the starting voltage to pass thru. For several years, I have used a screwdriver to bridge between the blade terminal on the solenoid and the main battery cable connection. This essentially is what the relay modification does. You can buy the John Deere kit with a plug&play harness and schematic, or you can buy the relay at most "Big Box" stores for around $12 and make up your own harness.

I've found the Kawasaki engine to be good but JD's design with all the wiring and devices is close to insane for what is it again.......Oh yes a riding lawn mower.......#%@(*!&.......I used the screwdriver trick on the solenoid for years to get it to go but alas that finally wasn't enough either.....so I wired in a hot bypass with momentary contact to get things purring but by then the electrics were toast. It was actually on my winter tadu list to rewire that whold dam machine but now springs here guess that didn't get done......

lynnl
04-04-2012, 12:26 AM
Seems to me that if the solenoid is good and all connections are good, that another relay in the circuit to try and do the job the solenoid is designed to do, is just redundant.
James

My thinking, in ordering the new solenoid, is that maybe, while it's getting enough juice to pull down the plunger in the solenoid and trip up the pinion on the starter rotor, the old one's contacts have arced and eroded to the point that at times it isn't making good enough contact internally to provide the 12 volts to the starter coils.

If this new solenoid doesn't solve the problem I'll know that was wrong and start trying to track down a problem in all of the other wiring and interlocks.

hardtail
04-04-2012, 12:46 AM
If I didn't know better I would believe that they contracted Lucas to do their electrics...........

The engines great, the mowers is fantastic but then theres the electrics.....if it would ever start I would park it behind the bulldozer just in case I decided to backup first one day........of course I could just start parking the dozer in it's general vicinty........LOL

J. Randall
04-04-2012, 11:30 PM
My thinking, in ordering the new solenoid, is that maybe, while it's getting enough juice to pull down the plunger in the solenoid and trip up the pinion on the starter rotor, the old one's contacts have arced and eroded to the point that at times it isn't making good enough contact internally to provide the 12 volts to the starter coils.

If this new solenoid doesn't solve the problem I'll know that was wrong and start trying to track down a problem in all of the other wiring and interlocks.

That is exactly where I would start also, and before I added another relay I would probably go with hardtails solution and wire in a starter button in an out of the way place that would not be that noticeable to anyone but the regular user.
James

darryl
04-05-2012, 12:38 AM
It used to be that you could grip the end of the contact bolt lightly with vise grips, then loosen the nut on it, push the bolt inwards until it will turn, give it a 180 turn, pull it back and tighten the nut again- all without taking it apart at all. Do this to both bolts, then hook up the wires again and it would work.

The heads on the contact bolts used to be square- maybe they still are. They nest into a molded hollow in the end of the solenoid, so they should seat into any of four positions. If you find that you can push them in far enough to turn them, then you have to make sure they pull back into the seated position again before you tighten the nuts.

There's a few things- first, if the solenoid clicks once when the key is turned, it's working. If it goes through a continuous clicking process, that usually means the battery is weak. So with one click when it's activated, you are basically bypassing any interlock features like seat switches, etc. You get a click, then ignore the switches, wiring, etc. Secondly, if it clicks, it's working, but maybe something is preventing it from moving all the way. If it has a fork that moves the gear outwards, something in that mechanism could be binding. If you can rule that out, then what's left is the probability that the internal heavy current contacts just aren't making it reliably. Try the trick of turning the contact bolts around.

There's usually a copper plate inside that gets rammed onto the heads of those contact bolts to make the connection when the solenoid is actuated. That plate is going to have spots where it's burned off. The possibility exists that you could also turn that plate around. Of course that would require taking the solenoid apart. But if you did this, you'd basically have a fresh set of high current contacts in place, and the solenoid should work for almost as long again as it did up till it started having problems.

Of course, one of the quickest and easiest ways to see if the contacts are bad is to bridge the contact bolts with a conductor of some sort. If the starter spins up every time when you do this, but doesn't spin up always when you activate the solenoid, then you've basically just proven that the high current contacts are bad. The thing to be aware of then is that if the gear relies on the fork activated by the solenoid to push it into engagement, then the motor might turn but not crank the engine. You would then know that the solenoid actuation must work, and that the contacts need attention.

Of course if they are cheap enough new, and easily obtained, you might be best served by buying a new one.

lynnl
04-05-2012, 01:04 PM
....

There's a few things- first, if the solenoid clicks once when the key is turned, it's working. If it goes through a continuous clicking process, that usually means the battery is weak. ....


Of course, one of the quickest and easiest ways to see if the contacts are bad is to bridge the contact bolts with a conductor of some sort. If the starter spins up every time when you do this, but doesn't spin up always when you activate the solenoid, then you've basically just proven that the high current contacts are bad. The thing to be aware of then is that if the gear relies on the fork activated by the solenoid to push it into engagement, then the motor might turn but not crank the engine. You would then know that the solenoid actuation must work, and that the contacts need attention.

Of course if they are cheap enough new, and easily obtained, you might be best served by buying a new one.

Yeah, I've already determined that I can start it by bridging the two main lugs on the bottom of the solenoid, while SIMULTANEOUSLY turning the "start" switch with the key.

So, when the key is turned, the solenoid is properly jerking down the plunger which in turn engages the pinion with the flywheel. But it's just not making good internal contact between the battery and starter.

But your comment about continuous clicking sheds some insight. I have occasionally encountered that, though not recently ...not in this latest series of problems. It would do that briefly and then after a time or two it would go ahead and drive the starter properly. In hindsight, with what I now know, I think it was not indicating a weak battery, but rather the bad connections and loss of voltage through some of those interlocks or switches.

Willy
04-05-2012, 01:15 PM
The conditions you describe are exactly those that burn electrical contacts.
High resistance leads to low voltage and high amperage requirements, this in turn burns the solenoid contacts.

Sooo, not to nag but when's that new solenoid getting hooked up?:D

bob_s
04-05-2012, 03:24 PM
First thing is to check the battery cable to see if it is sulphated.

If it is the resistance will be significantly higher.

lynnl
04-05-2012, 03:27 PM
Sooo, not to nag but when's that new solenoid getting hooked up?:D

Good question ... :D

Been wrestling with computer issues the last few days. Bought a laptop yesterday and shot the entire day shopping and getting it and a new router set up. Today I'm keeping a five year old grand daughter. (Anybody here ever play "My Little Pony"? :))

But I put down some lawn fertilizer, so I'll soon be forced to take action.

Speaking of fertilizer, what's up with that ...other than the price is sky high?
A bag of Scotts is around $50, and a bag of regular old triple-13 is almost $20!! Not hard to see why food prices are so high.