1988 S15 wil not start.

Greetings all,

Let me preface this with my admitting that I am not a "car guy". I have a basic understanding of how things work, slightly above average understanding of electrical circuits and probably way too many friends/acquantinances with advice. Please bear with me. :)

I have an 88 model S15 with a 2.8L engine that is really acting up. A few days ago it was acting a bit sluggish starting, like the battery was getting weak. It is a 2 yo Interstate but these things happen. Got up the next morning, it was sluggish again for 2 attempts then nothing. By nothing I mean there was no "action" from the starter. I hooked up my battery charger, flipped it to jump start, still nothing. Done some checking, I am getting power to the solenoid according to my light tester, so I suspected the solenoid itself to be bad. Removed solenoid and starter as a unit, took them to Oreilley and had them tested, passed test. The parts guy said that it could possibly be that it was not getting a good ground, so I took it back home, cleaned all mating surfaces, bolts, shims, posts and connectors, reassembled, still no love. GGGRRR!!! I am still getting a light with my tester when the key is turned to the start position, this is on the smaller post. I can not hear anything inside the engine compartment when the key is turned, I have a full display of lights on the dash with no dimming when attempting to start and I can also hear the fuel pump when the key is first turned on. I guess what I mean is there is no clicking from the solenoid, that I can hear, to indicate that it is working/getting power. I made a second trip to the parts store and was advised that I needed to check to see if the battery was putting out a full 12v, which I have not been able to do yet. But with the jump starter I would have thought that it would be putting out plenty of voltage, opinions?

I want to thank anyone and everyone in advance for any and all help/advice you might be able to give, this is my only means of getting to/from work so I really need to get this matter resolved soon.

Regards, Jim C Roberts

Reply to
Jim C Roberts
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First, try starting it in Neutral or moving the shift lever around while holding the key in start position to see if the neutral safety is out of adjustment. If no joy there, leave it in RUN position, emrg brake on, trans in park and use a jumper cable to jump from the positive terminal on the battery to the big terminal on the starter and see if that cranks the engine. If it does you know that the circuit that is supposed to operate the solenoid is not working right. Basically, start at the starter and work your way out.

Reply to
Ashton Crusher

"Ashton Crusher" wrote in message news: snipped-for-privacy@4ax.com...

Ashton,

First, thanks for your reply. Secondly, I have tried the moving the gear shift trick, did not work either, sorry that I did not include that in my OP. As for your other suggestion, I am a bit confused about the posts on the solenoid/starter. The best I can tell from looking at the assembly both on my truck and at the parts store is that the solenoid has 3 posts. 1 large one, ~3/8", and 2 smaller ones, ~#10. The larger one has 2 wires connected, 1 from the battery and 1 from a wiring harness, perhaps running to the alternator? 1 of the smaller ones has a wire connected to it from a wiring harness, this is the one that seems to energize the solenoid when the key is turned to Start. The 3rd post has a bus bar connected to it going to the starter itself. Is this where I need to connect the jumper cable? I want to think so, since it should complete the circuit engaging the starter. Although engaging the starter is not really correct is it? The starter will turn, but will it engage the flywheel? My rudimentary understanding of the solenoid/starter assembly is that the solenoid "throws" the running starter gear into the flywheel, correct? I think I can now see where your suggestion would prove advantageous. IF the starter spins when energized with the jumper cable then it pretty much shows that the solenoid is suspect. (Ashton, please don't take these last few sentences as "uppity", it just takes me a little while to verbally work through some things. Now if we were talking about how a high frequency TIG welder works or a pulse MIG I can keep up a little better. ;) I am still a little confused as to why it worked fine at the parts store but will not work in the truck, but it may be like the battery, no real reason for it not to work, it just doesn't.

Thanks again for your suggestions, I will try them and report back as to the success or failure.

Regards, Jim C Roberts

Reply to
Jim C Roberts

Greetings all,

Final diagnosis; Bad armature in the starter itself. After attempting Ashton's suggestions both in the vehicle and out with no success I returned to the parts store with the starter. A couple of rounds on the tester shut their machine down, dead short/overload. A tap on the starter would work for 1 or 2 more tries, then shut the machine down again. Purchased new starter/solenoid, installed, Joy on the first attempt!! Thank You Lord, Thank You Jesus!!! Oh yeah, Thank You Ashton too!!

Regards, Jim C Roberts

Reply to
Jim C Roberts

Hi!

Think about this. You've got what is nearly a twenty year old truck there, and it might be there already depending upon when GM put it together. Through the years both starter and solenoid have worked in bitter cold, burning heat and tons of dirt and ick that builds up one those parts over the years. The solenoid has had to put up with repeated makes and breaks which involved a few hundred amps of current to spin the starter motor.

The test you had done probably didn't place any sort of load against the starter motor, and it won't pull nearly as much power unloaded as it will turning that engine over!

Take a look at your starter solenoid. I think it is entirely possible that you have a worn out solenoid whose contacts are burnt up or degraded to the point where they won't even complete the circuit when the solenoid portion is energized.

Oh wait...I just read your "final diagnosis" post. Glad you got it fixed. I mentioned this and intended to post it anyway since the solenoid on my '84 GMC acted similar one day and crumbled to dust when I removed it in

2000/2001. The starter motor was still good, though.

William

Reply to
William R. Walsh

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