OT (Mostly) - Remember the Car Talk Puzzlers?

[A.K. Boomer]

Come to think of it --- the oversize alternator pulley did kinda make me laugh though lol so "good one"

[tomato coupe]

There was comedy thrown into the mix, but the "puzzler" questions were for real were they not? at least that's what the OP basically stated....

If not then the puzzler questions were a joke and ended with a "punch line" I really don't think that was the case was it???

The show clearly isn't for you.

[A.K. Boomer]

The show clearly isn't for you.

Correct - I thought we already covered that?

[A.K. Boomer]

For those interested --- I have a elementary "puzzler" sitting outside --- toyo/taco came in on the hook yesterday, "will not start" customer says on the phone they think the battery's dead,

it was about 4.30pm, I was done working for the day but wanted to quickly diagnose it to know what im up against for today because she lives in the mountains and can catch a ride to town later today....

so here you go, by the time you get done diagnosing this you should be left with only two simple choices, but one of the choices can be eliminated with common sense knowledge of basic operating principles,,,

Here's my 5 minute diagnoses that lead me to the answer - mind you - I don't have proof positive of the answer yet as I have not "fixed" the problem - but im very confident I know what's going on...

First things first --- I pop the hood and test the battery voltage --- it's 12.59 volts,,, its not the battery, secondly - I look at the batterys connections --- both positive and negative are clean as a whistle... ok ---------- head to the cab for a start, I instantly hear the small underdash relay click every time I turn the key to the start position, a millisecond after I hear that it's getting the "big boy" under the hood involved too, meaning the starter solenoid,

So i go into repeats with it - the vehicle is a 5 speed --- has to have the clutch pedal depressed to engage the starter - so I just do about 6 tries with the key and clutch pedal depressed, hear the "double click" of the relay and solenoid, then for the heck of it I lock the key in the start position and use the clutch pedal as a switch just to test it's integrity, all 6 more double clicks,,,

I already know it's one of two possibilities as most of you already do, but - im not content with that - I need to know more ---- so I go into a spastic engagement mode of repetitive attempts and finally get the starter to engage --- it turns over with ample "gusto" but then quits about 3 engine revolutions, was actually surprised the vehicle did not start --- I did want to get it started cuz the tow truck driver kinda left if too far out in the street so I kept at it again - and yet again got it to engage - but yet again about 3 revolutions and then it disengages ! damn and still no start,,, then third times a charm, get it to keep cranking and finally get it to clear its throat and start --- move the vehicle and re-park it,,,

I know it's the starter as most all of you do to --- but now I know what component in the starter is bad... the two choices were either brushes or solenoid contacts,,,

How did I determine it was one or the other?

So --- no takers on the above puzzle and how I knew what the in depth problemo was? vehicle is now fixed and it's exactly the problem I said it was,

got pics... somebody's going to get a gold star I just know it :-) was it brushes or solenoid contacts? and how did you arrive at the conclusion ?

[SVS]

I vote solenoid contacts.

The puzzlers were intentionally obfuscated. They were more “illustrations of possible truths” than TRUTH. Lots of times the answer involved something obscure like where on the car the gas filler was located, and using that fact to solve a “locked room” type mystery.

My wife hated the constant laughter, so no it wasn’t for everybody. More about thinking around corners, and regional variation in name spelling than actual technical data.

[A.K. Boomer]

I vote solenoid contacts.

Why?

[SVS]

Learned it from car talk……

Winding in bad spot, will probably never try, and won’t quit if it gets to rolling.

[Noitoen]

Why?

Because the main solonoid coil grounds through the armature which need the brushes to make this ground

[A.K. Boomer]

Learned it from car talk……

Winding in bad spot, will probably never try, and won’t quit if it gets to rolling.

But it did quit once it got "rolling" remember? in fact twice, so your first guess of solenoid was correct...

a dead spot in an armature will usually end up an intermittent disconnect - could vary from temperatures and stuff like that - and bad brushes or a dead spot in the armature will not "quit" once the starter motor gets going - they may arc and have reduced power but they will not just drop off with nothing more to give - too much variances in the armature run-out tolerance that will intermittently connect while running...

And Noitoen's is a good one but the solenoid actuation does not require a grounding through the starters brushes to make contact, it is an independent wire that excites the solenoids coils - the other end of the coil wire IS connected to the starter itself as a ground, but independent of the starters brushes...

So I guessed solenoid connections as in contacts - because I knew the coil was good and activating it - and also was almost positive the starters brushes were fine due to the starter cutting out instantly while running,,,

so first pic is going right to the source for "proof" of my theory and here's what i found;








This is actually very common - (but so are worn brushes)

anyways --- you can see the problemo, the contacts got very thinned out on one side --- it's a circular "solenoid plunger ring" that connects two copper 180 degree opposed pieces,,, the trouble with contacts of this nature is that one side always dominates meaning "is the first to engage" this leaves the other side to carry the "arc" every time, they may start out intermittently equal but as time goes by one side gets to engage and get established WITHOUT any electrical amperage to deal with - then the other side "loses" chunks of itself and gets even lower - then it snowballs and it's the one that takes the brunt every time,,,

the solenoid plunger goes up against a very heavy return spring,,, but once one contact side gets allot lower then the other it then has to "cock" the engagement ring on the plunger --- this too is built with a "cocking spring" to help with deviations,,, But it too takes energies to accomplish this,,,

so - hence the starter engaging once in a great while and actually running but then going into "disconnect" mode as the surface charge of the battery gets consumed and the solenoids coils get weaker and not enough to power both the robust plunger spring AND the cocking ring spring at the same time --- so even though it connected and got past the highest amperage draw factor (getting the starter going) it then disconnected after the solenoid could not hold it's positioning...

This hypothesis is what enabled me to tell the customer ahead of time - with just a simple 5 minute test at quitting time that she could pick up her car at such and such time the next day - even though I did not have brushes in stock, but did have a spare solenoid contact...

but make no mistake - I pulled the starters back cover and took a peep at the brushes just to make sure they had ample life left and they did - at least 3/4 life left probably more like 7/8's



So - these are the kinds of "puzzles" I deal with all the time and although while elementary you can see there are much finer details in the mix rather than just saying "it's got a bad starter" Or "it's got a bad solenoid"
Not exactly - the starter was actually in great condition including the bearing, and the solenoid was also in great shape except for one contact,,, the customer not only saved about 100 bucks --- I didn't have to bolt an "unknown" track record part back onto her vehicle - be it brand new or re-man, allot of parts are crap nowadays - or at least not up to the unit I repaired and put back into service...

She saved money and got a better job, and I made way more money than just being a monkey that bolted on a part...

[SVS]

I made one guess. Solenoid contacts.

[A.K. Boomer]

I made one guess. Solenoid contacts.

I now i see, your post in 52 was not another guess but was coming up with solenoid contacts due to it cannot be "winding in bad spot"

although that did not cover why it could not be starter brushes it's still looking at things in more detail,

Ok SVS - you get a GOLD STAR!!!!! good duty....

[Willy]

Missed this thread until just now, interesting read. Never had the chance to listen to the Car Talk Puzzlers show but I can appreciate AKB's disdain.
Likely one of the main reasons I stopped watching TV and movies for the most part. If you are going to be a critic, which I was, don't watch.

Wish I had 5 bucks for every time I had to crawl under a truck or a piece of equipment in order to smack the starter with a hammer so as to get the solenoid contacts in phase with the planets.
Brings back some fond memories. Well they weren't so fond at the time.

[Noitoen]

Unless the starter solonoids have changed lately, they had 2 windings. A "pull in" winding with thick wire connected to the solonoid contact together with the motor and a second thin wire "maintain with low current" winding, effectivly connected to the ground. This coil alone is unable to pull the solonoid in by itself.
The thick wire solonoid serves another very important function. Since it's connected i series with the motor it allows the motor to start rotating slowly aiding in the engaging of the stater's gear with the flywheel ring gear. Without ground through the brushes you will not hear the clicking of the starter.

[A.K. Boomer]

Unless the starter solonoids have changed lately, they had 2 windings. A "pull in" winding with thick wire connected to the solonoid contact together with the motor and a second thin wire "maintain with low current" winding, effectivly connected to the ground. This coil alone is unable to pull the solonoid in by itself.
The thick wire solonoid serves another very important function. Since it's connected i series with the motor it allows the motor to start rotating slowly aiding in the engaging of the stater's gear with the flywheel ring gear. Without ground through the brushes you will not hear the clicking of the starter.

You are correct SIr - it has both I did not look until right now as it's in the pic above ---- one is independent like I said but one CLEARLY goes to the starters brushes side like you said so your diagnoses is very good I just did not take you seriously cuz you gave a sticking out your tongue guy after it lol

I think your right the system is a "start-up" for engagement and might also allow for boosting and adding to the initial coils main windings that are more responsible for solenoid engagement --- but those are the independent smaller wire not the bigger ones...



So for diligent Duty - and for taking your thinking to a higher level,,, I have to award another GOLD STAR to Noitoen... initial coil had the umph to get the job done - but contacts bad - yet once in a great while they connected - and even with the "fortifier" coil they were still was not enough and I think that's due to my one explanation of there being too much resistance to overcome - both the main spring and the one that allows of deviation/cocking - therefore after about 3 revolutions the surface charge got yanked off of the battery and Both coils suffered holding power losses and contacts disconnected...

Thanks for chiming in guys and making this fun I like to speculate on the theory of "why" too.

[A.K. Boomer]

Missed this thread until just now, interesting read. Never had the chance to listen to the Car Talk Puzzlers show but I can appreciate AKB's disdain.
Likely one of the main reasons I stopped watching TV and movies for the most part. If you are going to be a critic, which I was, don't watch.

Wish I had 5 bucks for every time I had to crawl under a truck or a piece of equipment in order to smack the starter with a hammer so as to get the solenoid contacts in phase with the planets.
Brings back some fond memories. Well they weren't so fond at the time.

Yes the old smack the starter with a hammer trick - really works great if you have someone in the cab spring loading the key and then usually just one "tap" and it's off and running... in that case - kinda hard to pick apart what was wrong - as that trick works good for both bad brushes and bad solenoid contacts....

I would say if it's working and you don't have anyone in the cab to load the starter and it still works after you get out and tap the starter then get back in that it's leaning more towards brushes at that point....

Willy - ever try not even getting out of the vehicle and just loading the key and then a major (almost dent the floorboard) stomp on the belly pan ?

I did try that with this vehicle and it did not engage - but can attest Iv created enough "change" to get a starter to engage once in awhile as it vibrates the whole vehicle and that's what your looking for,,, nothing like a tap on the culprit with a hammer but damn in the dead of winter it's worth a shot rather then getting out in the cold.... plus your already pissed off - might as well take advantage of it lol