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Ok here we go... I've got a 2002 Trailblazer LT with 67,000 miles. Not all of the time but most of the time this happens, when I start the vehicle its like the starter is to slow to disengage itself in time and makes a noticable grinding sound. Could it be just the starter is on its way out. I'd hate to throw parts at it and not correct the problem.
What do ya'll think ?
 

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with starters, when you apply the key- theres a little device that pushes (solenoid I think theyre called) the starters gear forward to engage the flywheel. once its done- its pulled back and it no longer engages the flywheel.
2 things can happen.
the solenoid fails and the starter turns- you hear a whirring sound as the starters spins in place........... the gear never moves and never touches the flywheel.

the other thing that can happen is that the solenoid gets lazy or the spring mechanism that pulls it back also weakens or fails..... when this happens, you hear the starter engage the flywheel, engine starts, but it then doesnt let go and you have the engine turning the starter...... makes a very distinct noise.
it could also be that the starter needs to be shimmed. they add these little spacers (shims) to make the started straight and keep the grinding sound from happening.
though I have not read about this on here........
very common on older chevys friends had... wed buy shims- put them on and problem solved.
 

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Starter

I agree with the above comment, but another problem is the shaft that the bendix(the started motor gear) gets dry and the bendiks is slow in returning.I do not know if this is the case for our trucks but I have had problems on other vehicles before so I would try this:confused:
 

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:iagree: I think you hit it on the head. It really sounds like a slow Bendix operation. Probably gonna have to change the starter ....sooner than later. I hate getting stranded. Especially if it knocks some teeth off the ring gear! :x
 

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Did they put the starters in an easy to get to spot on these things? On my '91 blazer the stupid starter went out multiple times and I had the remove the front driveshaft in order to remove the dust cover, in order to remove the starter. Total pain in the butt. I eventually started driving it around without a aluminum dust cover.
 

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Bad bendix

Years ago you could actually rebuilt just the bendix I don't think that's an option any more but you might be able to pull the starter and lube the shaft and bearing at the tip of bendix :undecided
 

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Did they put the starters in an easy to get to spot on these things?
:laugh: you will need two people to do this job.... I removed the PCM to get ample space b/c the starter is below the PCM. When i did mine, I had my friend on the ground under the truck and i crawled in the engine bay and removed the starter and aligned it while he took all the bolts and connections off. its a major PITA. I had the the same problem you did too... it would crank really slow and sometimes the gear would slip and grind the flywheel. New starter fixed it. I got it off ebay, brand new (non oem) for less than 100 dollars. Took about 1-1/2 hrs to install.
 

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with starters, when you apply the key- theres a little device that pushes (solenoid I think theyre called) the starters gear forward to engage the flywheel. once its done- its pulled back and it no longer engages the flywheel.
2 things can happen.
the solenoid fails and the starter turns- you hear a whirring sound as the starters spins in place........... the gear never moves and never touches the flywheel.

the other thing that can happen is that the solenoid gets lazy or the spring mechanism that pulls it back also weakens or fails..... when this happens, you hear the starter engage the flywheel, engine starts, but it then doesnt let go and you have the engine turning the starter...... makes a very distinct noise.
it could also be that the starter needs to be shimmed. they add these little spacers (shims) to make the started straight and keep the grinding sound from happening.
though I have not read about this on here........
very common on older chevys friends had... wed buy shims- put them on and problem solved.
Its called the bendix.. not the selinoid
with starters, when you apply the key- theres a little device that pushes (solenoid I think theyre called) the starters gear forward to engage the flywheel. once its done- its pulled back and it no longer engages the flywheel.
2 things can happen.
the solenoid fails and the starter turns- you hear a whirring sound as the starters spins in place........... the gear never moves and never touches the flywheel.

the other thing that can happen is that the solenoid gets lazy or the spring mechanism that pulls it back also weakens or fails..... when this happens, you hear the starter engage the flywheel, engine starts, but it then doesnt let go and you have the engine turning the starter...... makes a very distinct noise.
it could also be that the starter needs to be shimmed. they add these little spacers (shims) to make the started straight and keep the grinding sound from happening.
though I have not read about this on here........
very common on older chevys friends had... wed buy shims- put them on and problem solved.
Its called the bendix..
 

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Ok here we go... I've got a 2002 Trailblazer LT with 67,000 miles. Not all of the time but most of the time this happens, when I start the vehicle its like the starter is to slow to disengage itself in time and makes a noticable grinding sound. Could it be just the starter is on its way out. I'd hate to throw parts at it and not correct the problem.
What do ya'll think ?
I think that if you can't be bothered to reply to a post you started over a decade ago, you don't really give a crap what we think.
with starters, when you apply the key- theres a little device that pushes (solenoid I think theyre called) the starters gear forward to engage the flywheel. once its done- its pulled back and it no longer engages the flywheel.
Yes. The solenoid pushes the starter drive via the "shift fork". The solenoid plunger and shift fork is spring-loaded so the starter drive is pulled away from the ring gear when power to the solenoid "S" terminal is disconnected.
2 things can happen.
the solenoid fails and the starter turns- you hear a whirring sound as the starters spins in place........... the gear never moves and never touches the flywheel.
No. The starter can't crank unless the starter drive is pushed forward. The solenoid is designed to not make the electrical contact with the starter motor unless the drive is pushed back to engage the flywheel teeth.

What you're describing is a failed (slipping) starter drive. Starter motor cranks, starter drive slips, crankshaft does not turn.

+1 for bendix...new starter time
Bad bendix
Years ago you could actually rebuilt just the bendix I don't think that's an option any more but you might be able to pull the starter and lube the shaft and bearing at the tip of bendix
"Bendix" is a brand name. The name of the part is "starter drive". Not all starter drives are made by the Bendix Corporation. Starter drives were never rebuildable in my experience, but they were easily replaced.

you will need two people to do this job.... I removed the PCM to get ample space b/c the starter is below the PCM.
Inline six 4.2L Vortec? Go in from the driver's side wheel well. Not from the top. One person job. Not hugely fun, but very do-able.
Its called the bendix.. not the selinoid

Its called the bendix..
Solenoid not selenoid..my bad lol
It's not called a "bendix", and it's not a selenoid. The person you're "correcting" was right. The solenoid on the starter motor causes the starter drive to be pushed into engagement with the ring gear teeth. Once engaged, the starter motor activates to crank the engine.
 

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There's a lot of good information here so far.... but.....

GM starters do not have a Bendix Drive. A Bendix drive is a passive gear, a coil spring and a ramp cut into the starter motor shaft that when the motor spools up, the gear winds up the recoil spring and it jumps into the flywheel gear teeth.

Ultimately, the gear starts spinning and slams into the ring gear. This is why GM won't//doesn't use them.

That's it's sole purpose, physics-wise anyway. Let me see if I can find a picture of a true Bendix Drive.... brb....

55141

The gear on a Bendix Drive can face either away from the starter motor or toward the starter motor. It doesn't matter - they both just spin and then slam into the ring gear.

GM uses a solenoid that by it's action forces the gear into the flywheel first, then spins the motor once the solenoid reaches full travel and the gear is fully into the ring gear. .
  • A GM Delco-Remy style solenoid is mounted ON the starter and has mechanical linkage to move the gear drive into position.
  • The positive battery cable goes directly to the big stud on the starter solenoid, and that connection has been used in the past as a BUSS Terminal for the heavy Amperage devices on the vehicle. That job is now handled primarily by the fuse panel on the driver's fender
  • A Bendix Drive usually has a solenoid on a fender or firewall and it is there to handle the high Amps that the starter needs to run the motor to spin the engine - etc, etc, etc.
  • Many times, this B+ post on the solenoid is also used as the heavy Amperage Buss Terminal for Ford vehicles. That isn't written in stone - it just USED TO BE that way.....Ford used to put their fusable links here too.
GM has even gone to a newer version of their great starter drives with a "Soft Start" option....where they start gently turning the starter motor to help it get into contact with the ring gear a littler more easily.



This next video is a really good explanation of the Delco-Remy Style starter drive. If you can understand the British twang, it should be a good lesson...





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