Why does my starter labour when it's hot?!

[rang-a-stang]

My truck has done this since I got it running. When the motor is warm or hot it labours to turn the motor over, sometimes. It's not consistent.

I have replaced:
The starter
the cable between the starter and the solenoid
the cable between the solenoid and the battery
the battery
the ground cable
I have not replaced the solenoid because the previous owner said he did and it looks new.
My timing is at 10 degrees and I am going BONKERS trying to get this truck to start when it's warm/hot!
When the starter does finally get the motor turning, it fires right up into a low idle. I don't understand what could possibly be doing this, that I haven't already replaced.

Should I make a heat shield for my starter? Does anyone else's do this?! GGGrrrr.....

[joe]

First guess is ign timing is too far advanced. 2nd guess would be timing chain is seriously stretched and sloppy.

[Don S]

..

Could also be somewhat flooded with fuel.

By the way have you noticed everybody here has an FSJ related avatar.

Just sayin'.. Good luck.. Don S..

[440sixpack]

Timing is a something to check, but normally you can tell it's kicking back if that's the problem.

I fought this on a '70 AMX I had and I did two things that fixed it. I put a heavier cable from the battery to the starter and I put a higher amp battery in it. but this was a built high compression engine.


This isn't normally the symptom of a failing solenoid, I would expect it to weld itself if it was making poor contact. and maybe it will. as cheap as solenoids are I'd replace it to rule it out. or next time it does it jump the solenoid and see if it turns over like it should. either one would rule it out.

[bufurd]

Easy to see if it's timing, pull the coil wire or power wire to ignition and see if it spins like it should. An old hotrod trick was to put a toggle switch in ignition feed, ya flip it on once engine was spinning..

[rang-a-stang]

Easy to see if it's timing, pull the coil wire or power wire to ignition and see if it spins like it should. An old hotrod trick was to put a toggle switch in ignition feed, ya flip it on once engine was spinning..

First guess is ign timing is too far advanced. 2nd guess would be timing chain is seriously stretched and sloppy.

Even when my timing was at 6* (Factory setting for smog check) it was doing this. Next time it does this (probably tomorrow since I am driving it to work tomorrow) I will try your suggestions, buford, and unhook the coil to see if that makes a difference.
Cam chat? Crap. Could be. I have no idea the internal status or even the mileage of this motor. Anyway to check it without pulling the chain cover? It idles like a swiss watch, though...

..
Could also be somewhat flooded with fuel.
By the way have you noticed everybody here has an FSJ related avatar.
Just sayin'.. Good luck.. Don S..

I hear you, Don. That's my avatar for literally, every website I can use an avatar on (paypal, Mazdaspeed forums, my work websites both on the unclassified and classified sides, etc.). I have been using it for about 10 years now. I will consider changing it for this site, though since you politely mentioned it.
I am hesitant to attack fuel only because once it does get turning, it starts pretty much instantly. Its one of the quickest starting carb'ed engines I have ever owned (once the starter actually kicks it over).

Timing is a something to check, but normally you can tell it's kicking back if that's the problem.

I fought this on a '70 AMX I had and I did two things that fixed it. I put a heavier cable from the battery to the starter and I put a higher amp battery in it. but this was a built high compression engine.


This isn't normally the symptom of a failing solenoid, I would expect it to weld itself if it was making poor contact. and maybe it will. as cheap as solenoids are I'd replace it to rule it out. or next time it does it jump the solenoid and see if it turns over like it should. either one would rule it out.

1) I will verify my timing tomorrow but I'm 90% sure its at 10* and like you said, I would think it would run like crap if it was so far advanced that was hard to start.
2) The battery I bought was a Costco Interstate. The cables were 10gauge I think (pretty fat). SOMETHING is failing though. Everyone else doesn't have this problem and it my truck is pretty much stock so the stock starting system should work.
3) I have a known good extra solenoid from an old Falcon Wagon I had so I'll throw it in just to check.

[Heep-J4000]

My J4000 did this too when engine hot or on hot days.
At first i made a heatshield between starter and exhaust manifold ,did not help,
Much later i burned the starter solenoid afther running out of fuel
Had to put a new solenoid in and it never happened again ,so it's worth a try to go for a new or other solenoid.

[rang-a-stang]

My J4000 did this too when engine hot or on hot days.
At first i made a heatshield between starter and exhaust manifold ,did not help,
Much later i burned the starter solenoid afther running out of fuel
Had to put a new solenoid in and it never happened again ,so it's worth a try to go for a new or other solenoid.

Oh dear Lord I hope this is the case for me!

[twmattox]

Double check your grounds. I was missing one from the engine to the frame and I had hard start issues (though generally all the time).

[rang-a-stang]

Copy. I have the battery ground wire attached at the A/C pump bracket. I cleaned the mounting position when I installed the new battery. I also have a specific body ground wire I added when I was having gauge cluster problems.

Tonight i checked my timing: 10* spot. Tomorrow I will replace the solenoid. It's literally the ONLY thing that I have not replaced.

[babywag]

Even new stuff can't be ruled out...
The off the shelf battery cables these days are pretty much junk.
A reman starter can also be junk right out of box.
Have the starter tested, most parts stores have tester, see what it draws when warm/hot.

[rang-a-stang]

I agree. (Even new stuff can't be ruled out...)

I bought a solenoid on my way to work today and will install it at lunch. Then I hope to make it to an exhaust shop for a couple estimates. We'll see if the solenoid makes a difference.

The starter I bought said it was new when I bought it but it had a FOMOCO logo on the housing. LOL! I didn't really care because it was $36 from RockAuto.

If the Solenoid does not make a difference I will pull the starter and bring it to AZ for testing.

[twmattox]

Another possibility is that the harmonic balancer has shifted or the timing chain was not installed properly (some have alternate installation configuration).

In other words, I have seen some where the mark for TDC is NOT TDC. I would remove the #1 plug and verify...

[rang-a-stang]

I put my new solenoid on my truck, op tested it twice, and it worked wonderfully so I put my tools away, got all excited to go to the exhaust shop, then went to start my truck and the solenoid stuck closed. I rush out and pull the negative cable to stop the starter from spinning. I tapped the new solenoid with a wrench and hook the battery back up and it sits nicely as it should. I went in, turned the key and it did the same thing (stuck closed). So I put my old solenoid back on and head back to my desk with my head held low.

I am also noticing that I have a pink wire connected to the back side of my solenoid (Starter motor side) that I do not know what it goes to. I do not see it on the wiring diagrams, either. I see I have battery (+) and Yellow connected to the left, LT Blue to S, Red to I, and starter motor and pink to the right.

[440sixpack]

Not sure about the wiring on your year of Jeep.

Sounds like you got a bum solenoid. not uncommon with the Chinese junk we get these days.

try another one , but keep in mind low voltage can weld a solenoid.