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  • lynnl
    replied
    Originally posted by Willy
    Sooo, not to nag but when's that new solenoid getting hooked up?
    Good question ...

    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.

    Leave a comment:


  • bob_s
    replied
    First thing is to check the battery cable to see if it is sulphated.

    If it is the resistance will be significantly higher.

    Leave a comment:


  • Willy
    replied
    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?

    Leave a comment:


  • lynnl
    replied
    Originally posted by darryl
    ....

    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.

    Leave a comment:


  • darryl
    replied
    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.
    Last edited by darryl; 04-05-2012, 12:48 AM.

    Leave a comment:


  • J. Randall
    replied
    Originally posted by lynnl
    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

    Leave a comment:


  • hardtail
    replied
    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

    Leave a comment:


  • lynnl
    replied
    Originally posted by J. Randall
    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.

    Leave a comment:


  • hardtail
    replied
    Originally posted by Jim Caudill
    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......
    Last edited by hardtail; 04-04-2012, 12:36 AM.

    Leave a comment:


  • Bob Ford
    replied
    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

    Leave a comment:


  • J. Randall
    replied
    Originally posted by Jim Caudill
    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

    Leave a comment:


  • Jim Caudill
    replied
    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.

    Leave a comment:


  • J. Randall
    replied
    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

    Leave a comment:


  • lynnl
    replied
    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.

    Leave a comment:


  • Jim Caudill
    replied
    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.

    Leave a comment:

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