Starter bendix not engaging

[Etheridege]

So I am still having difficulties with my '96 Yukon. I won't go into all the details (here is the thread detailing what problems I had and how I got it started. http://www.tahoeyukonforum.com/forum/showthread.php?t=55783) I finally got it running only to have it later fail to start. When I went to restart I just got the spinning sound from the starter and no flywheel engaging. Thinking it was the starter or solenoid failing. I took it off and had it bench tested at two parts places and it passed both times. I saw the starter throw pinion out and spin the bendix. I reinstalled the starter but I still go no bendix/flywheel contact. I can hear the pinion getting pushed out and the bendix spinning when attempting to start.

I have a good battery and I replaced the positive cable and then checked for voltage drop with my multimeter. Everything was fine with no drop. Flywheel is fine, no missing teeth.

Could a problem with the ignition coil prevent the pinion from coming all the way out to engage? Or the starter relay? I checked the starter relay with my multimeter and it read a resistance of .07 when multimeter set at 20k. I didn't power the relay to listen for the "click" though.

I appreciate any input or suggestions anyone may have. Getting desperate.

Thanks

 

[SunlitComet]

check to see if the mounting boss on the block is damaged or a possible misalignment of the starter install.

 

[retorq]

You are using real starter bolts and not normal hardware bolts right?? No alignment shims or anything??

 

[Etheridege]

Original starter bolts, no shims

I am using the original starter bolts and no shims. I am going to loosen the starter and see if I can reposition the starter a bit. It doesn't appear to be askew but I will check it out and see.

A friend of mine said that the starter could still pass a bench test but not start the vehicle. He mentioned that there is a spring that if damaged/broken could cause the pinion to free spin while the bendix stayed in one position, even if engaged to the flywheel, thus causing the whirr you hear. The bench test would show the bendix spinning, but when against the flywheel the resistance would only spin the pinion because the spring was broken/damaged. I only had a brief conversation with him in this regard and this is what I remember (sort of). Could anyone verify, or clarify this?

Thanks again for all your help.

 

[mudslinger96]

Had the same problem in my Yukon with the bendix being bad. You could simply take it to get fixed I fixed mine myself just got the parts at a local shop that fixes starters and altetnators. Got the parts for about $10.

 

[SunlitComet]

I am using the original starter bolts and no shims. I am going to loosen the starter and see if I can reposition the starter a bit. It doesn't appear to be askew but I will check it out and see.

A friend of mine said that the starter could still pass a bench test but not start the vehicle. He mentioned that there is a spring that if damaged/broken could cause the pinion to free spin while the bendix stayed in one position, even if engaged to the flywheel, thus causing the whirr you hear. The bench test would show the bendix spinning, but when against the flywheel the resistance would only spin the pinion because the spring was broken/damaged. I only had a brief conversation with him in this regard and this is what I remember (sort of). Could anyone verify, or clarify this?

Thanks again for all your help.

you are talking the the clutch and yes it could be broken. Since there is no resistance in bench testing it would just spin with the motor.