Starter damage on track

[Hermes]

I got some strange starter damage on track this weekend and was wondering if anyone has ever seen anything like this or has any theories.

After coming off track at the end of a session, I heard light zing and ticking sounds which were engine speed related. Just as I turned into my parking spot I blipped the throttle heard a light pop and the sound went away. I thought maybe I picked up some debris that was rubbing against a pulley, but I couldn't find anything on the ground. I left the car running and looked under hood and everything sounded and appeared to be normal.

When I went to start the car for my next session the starter gear did not engage the fly wheel so I loaded up, bump started the car and drove home [over 600 miles from Road America to Rochester NY]. When I got home I removed the starter and noted the last 4 mm of the gear was ground off as was about 1 mm of the housing face. This appears to have been machined by the flywheel. It would have had to move over 1/4" to do this. I plan to take some measurements from the flywheel to the mounting flange and will likely pull the tranny this weekend. Here's a picture showing the damage to the starter gear teeth as well as the surface that appears to have been machined by the spinning flywheel. By the way the car drove great on the way home, no vibrations, good power, etc.

 

[Berol]

That is really strange.

Dropping the transmission is a good idea to check if there is any debris in the bell housing. Would also be good to give the flywheel a good look over at this time too.

Were all 3 starter bolts snug when you went to remove the starter?

Not sure if you're still on the stock clutch, but I'd also consider replacing the clutch just to improve shifting. This is especially true if you notice any damage to the flywheel that require it to be replaced.

 

[06mach1]

I wonder if the ring gear moved on the flywheel. Once the started teeth were damaged, they would no longer mesh with the ring gear.

 

[ArizonaBOSS]

I've never seen anything like that before.

Might want to look into the starter solenoid and/or relay, and their associated wiring to make sure nothing was melted/shorted by the exhaust or some other issue that could have caused the starter to engage or protrude during engine operation.

 

[moto]

It looks like the starter didn't disengage all the way and probably just means the starter went bad. I doubt it damaged the flywheel at all but you should be able to visually look at it? I bet the damage on the housing was from the metal grinding off the teeth.

 

[TMSBOSS]

I wonder if the ring gear moved on the flywheel. Once the started teeth were damaged, they would no longer mesh with the ring gear.

Good point!! Somehow the relationship between the flywheel and or ring gear and the starter changed. Did the ring gear come closer or did the starter move to the flywheel???

Front to rear play of the flywheel is not a likely cause. Flywheel being loose, also not likely. Ring gear moving on flywheel could be it if the starter was tight.

As a minimum I would want to look at the ring gear. If this much damage was done to the starter, how is the ring gear??

If you are still on stock parts; clutch, flywheel, release and pilot bearing. Now would be a good time to replace and or move up.

The wear on the starter housing looks like its flush making me think the starter was firmly bolted in. This points more to a ring gear "Wandering".

Good luck with the repairs. Lets us know what you find.

 

[Hermes]

Thanks for all the great feedback.

The starter was tight onto the bell housing
I just checked the ring gear and it does not appear to have shifted, but I can't tell for sure without a new flywheel to reference.
I don't think this was a result of the starter gear engaging the flywheel. It may not be clear from the picture, but the stationary starter housing face was machined by whatever cut into the gear. Something that appears to have a diameter similar to the flywheel.
The ring gear teeth appear undamaged. They appear to be hardened and the starter gear is clearly soft by the way the metal smeared.

I just measured distance from the starter mounting face to the flywheel ring gear at 13.5 mm. Distance on the starter from the end of the gear to the mounting face is 17 mm. This indicates the flywheel in out of position by more than 4 mm toward the engine side and would probably chew up a new starter the same way.

Weird stuff!! I'll try to pull the trans this weekend.

 

[ArizonaBOSS]

If the flywheel is really out of position, I would think you would have some MAJOR problems and felt that at a bare minimum as a terrible vibration.

 

[TMSBOSS]

Are the clutch and fly wheel stock?

 

[Hermes]

ArizonaBOSS, I agree, it makes no sense that the flywheel would have shifted and that the car feels normal. Clutch engagement is normal, the engine and car feels very smooth driving [no vibration].

TMSBOSS, yes everything is stock on the entire powertrain and never been apart. I have about 36k miles on the car and never had any problems other than a couple of catalytic converter codes that were covered under warranty.

Won't have a chance to pull the tranny until this weekend. Hopefully that will reveal what happened.

 

[302 Hi Pro]

I have to agree with Drew, as the pic of the starter seems show the drive gear is partially extended. It pops in and out of the starter housing to engage the flywheel teeth. This is a probable cause why your measurements show contact between the driven and drive gears, (flywheel ring gear to starter drive gear related to the starter mount).

Once you have a new starter in hand to compare to the failed unit this should become apparent. It could be a failed starter drive, ground or wiring issue, (heat melted harness), etc., that caused the starter not to disengage. The housing wear is from debris while the teeth were being sheared.

These are very tight tolerances and shims are also available to ensure proper starter clearance is achieved upon install. You are right the starter bendix teeth are sacrificial.

Start with the easy things first, replace the starter and go from there. If you still have problems with clearence then tear in to the clutch and flywheel replacement. Just sharing my thoughts.

Keep us posted and good luck with your repairs,
302 Hi Pro

 

[Grant 302]

I've never seen anything like that before.

Might want to look into the starter solenoid and/or relay, and their associated wiring to make sure nothing was melted/shorted by the exhaust or some other issue that could have caused the starter to engage or protrude during engine operation.

+1!

I suspect an internal short related to the solenoid. Or something physically damaged prevented the gear from retracting fully. I'd check everything like Drew mentions above before trying a new starter.

 

[superhero]

seeing how it also wore the housing to the starter. It would have to be loose bolts on the starter. Do these cars have shims like others brands do??
If the starter had an electrical problem it would of only wore the gears and not he housing.
Assuming its the factory starter.
No way its the flywheel.
Last question...was the starter factory and was it ever out of the car to install headers or other mods??

 

[thehueypilot]

From the damage on the starter housing itself it looks like a loose flywheel contacted the starter housing as it matches up with the OD teeth on the flywheel's ring gear. It looks like it took out (machined off) each drive gear tooth as it forced it to turn. A loose flywheel would not always give you a vibration. I had a loose flex plate once (automatic transmission) that started moving around and elongating the mounting holes until finally it started making a clunking noise only when idling but had no vibration. I got black flagged as they thought the motor was going to throw a rod. I would check the flywheel's ring gear teeth as they might have issues as well. You could pry on the flywheel through the starter's mounting hole to see if it moves in and out before you pull the transmission. Good luck.

Tim

 

[k98dave]

I would think you could roll the engine over using the front crank pulley bolt with a wrench and check the flywheel ring gear for any signs of movement or marks. Actually I think you just had a stater fail. You said you heard a "zing" which sounded like the starter was still spining. I have seen this before when starters stay fully or partially engaged. If everything looks ok I would get a new starter and the start relay, and check starter harness for any shorts or damage. Compare the new starter gear with the old one and see if it failed to retract completely. I would try that before going thru trouble of pulling trans.

 

[El_Tortuga]

Count me in on the crowd that would assume bad starter bendix/wiring hanging it out in the engaged position as the most likely scenario. I'd certainly examine the flywheel closely to check if it has any chance of being loose. Let us know how it ends up.

 

[TMSBOSS]

With the grinding on the starter housing a simple starter drive is ruled out. Did the starter come loose and cock in the opening? Not likely. The loose or missing bolts would have been obvious on tear down.

I am leaning to a rind gear which has moved towards the face of the flywheel of a loose flywheel. I hope I am wrong. Not cheap fixes.

 

[SDS]

I had a similar problem with the starter gear grinding down.

Hot day on track and noticed a metal on metal screech pulling into the paddock.

The flywheel ring gear on my Mceod lighted steel unit is a press fit. The gear pulled away about 1/4" out of plane with the flywheel core on one spot. It was making contact with base of the starter gear and had destroyed the starter gear.

New clutch, flywheel, and starter and I'm back in business. Had the work done at Borelli's in San Jose and they hadn't seen this problem before.

FWIW, Check the flywheel for any gaps with the ring gear.

Steve

 

[302 Hi Pro]

I had a similar problem with the starter gear grinding down.

Hot day on track and noticed a metal on metal screech pulling into the paddock.

The flywheel ring gear on my Mceod lighted steel unit is a press fit. The gear pulled away about 1/4" out of plane with the flywheel core on one spot. It was making contact with base of the starter gear and had destroyed the starter gear.

New clutch, flywheel, and starter and I'm back in business. Had the work done at Borelli's in San Jose and they hadn't seen this problem before.

FWIW, Check the flywheel for any gaps with the ring gear.

Steve

Steve, thanks for posting this info on a McLeod ring gear failure, I've never seen this happen either. One more reason why I'm not a McLeod fan.

Your FWIW recommendation is very important to inspect the flywheel as one thing I've found in life is anything is possible. It could be damaged and/or slipped out of seat.

This is when you realize just how much you miss the inspection cover!

Thanks again,
2HP

 

[Hermes]

I did look into the gear ring possibly shifting, the front face of the gear is slightly behind the front face of the flywheel so it's not obvious that it has moved, but without a new flywheel to compare to, I can't tell for sure.

I did see something that was somewhat disturbing last night. I had my wife look at the front crank pulley while I pried the flywheel away from the engine and while I could not see any movement in the back, she said she saw it move about 1/4". Could be a good chance that I somehow lost the thrust bearing / washer on the engine. Now my course of action will be to pull the engine rather that the trans. It will be more work, but either way I'll have access to the flywheel and clutch. I'll just also gain access to the engine internals in case it is a bad thrust bearing / washer. The service manual shows the last lower crank bearing works in conjunction with an upper thrust washer to provide crank thrust control. Hopefully, there isn't too much damage inside when I get everything apart, after all it ran 700 + miles home from the track without any issues. I got it started last night to back it into the garage to make an engine pull easier and everything ran and sounded normal. I'll post some pictures and additional discussion once I get this sorted out. Hopefully no one else runs into this problem, cause it's turning out to be a lot worse than just a starter replacement.

Thanks to everyone for all the input. The response on this forum has been great.