I installed a fidanza flywheel that was to fat and it caused interference with my bell housing. The car turned over but it damaged the outer edge of my original 102k mile ring gear... I went back to the factory flywheel and 'OEM' junk ring gear...

I just got my car back together. I put a KEP ring gear in. The ring only needed a light tap with a rubber mallet to seat. The starter sounds perfect just as before. Now, every time I go to start I'm wondering if it will work. Here's hoping this will be the end of it. I'll keep you posted as time goes on.

My two cents....
 

I think the heating of the ring gear is not such a good idea....I would prefer putting the ring gear in the sun and letting it set for a while and putting the pressure plate in the freezer. Having said that I have to agree with others, I have never had to do that. Normally they just tap on with a plastic mallet.

Now with the ring gear damage, you have to consider that the broken parts from one ring gear could cause castatrophic damage, not to mention two or three.
The problem at hand could be the result of previous weakening by the starter.

Also you need to consider that the starter might be the issue as well. What does the teeth look like on the starter gear. Did the starter completely retract after the start...a culprit could be a bad solenoid.

In aircraft, we see engine kickback that also causes starter ring failure.

Just some other things to consider.

It's been over a month now since I put in the KEP ring gear and everything is working great! I'm convinced the problem was either brittle metal in the OEM ring gears or heating the ring to help installation caused weakening of the teeth.
Here's hoping this is the end of my starting problems.

Well I went to start my car yesterday and guess what the starter just buzzed... I almost had heart failure... Immediately i rushed under the car praying it was just a starter problem.

After pulling the starter this is what I saw. It should be noted that I installed a new starter gear on the IMI starter when I installed the new Ring Gear.
http://forums.pelicanparts.com/uploa...1346346226.jpg

I immediately called IMI They then asked me to measure the depth to the Ring Gear. Mine was 34mm. i was then told that the start is coming out to far and I need to install a shim to prevent this. I was also told that they would send me a new starter gear. I was happy to hear they weren't going to charge me. I just really hope that this works... Frankly I'm thinking about just going back to a stock starter...

http://forums.pelicanparts.com/uploa...1346346539.jpg

Okay, I pulled the engine out of my race car because I needed to replace the clutch disc and send the pressure plate out to Kennedy to get the friction surface replaced. My ring gear had two teeth broken off this time which isn't too bad.

I ordered and installed a new pinion gear on the Hi Torque starter. The old one looks beat up compared to the new one. I'll have Kennedy send one of their ring gears to me when they send the pressure plate back.

tshebib, how is your Kennedy ring gear holding up? Have you had a chance to look at it recently? How about you, curoswiss? How is your ring gear and starter behaving?

Thanks,

Scott

Scott,

The car starts everytime without hesitation. It was a good month after I installed the Kennedy ring that I would jump in the car and not wonder if it would start. All is perfect so far- well, except now I need better brakes and suspension (the journey continues...)

Tom

Tom,

That is good to hear!! My brakes and suspension are great, I just need to good starter pinion gear and ring gear setup!!!

Scott

Hi Scott, yes all is good for me now... I also fixed my MFI cold start also and the prevents endless cranking...

Is it possible that the "Hi Torque" starter may be causing ring gear problems?

Did you read the whole thread? How about the first post?

Scott

Peter,

Would you ask Hayden this question?

Thanks,

Scott

update - possible cause

Whilst talking to the Kennedy Engineered Products folks yesterday regarding a different issue

I learned that certain Bosch 911 "cold weather" (i.e. high-torq) starters, like the one I bought new from Stoddards (1.5 HP) can cause this damaged ring gear problem

they quit using-selling the Bosch starters for this reason

it seems they have a thin nose bushing that "cracks" if you get a engine kickback while cranking

- and once that happens the pinion will be out of tolerance and start eating up the ring gear

(or maybe it just wears, with same result)

here is an old thread with a lot of chat about the IMI depth problem -
http://www.914world.com/bbs2/index.php?showtopic=75173&st=

BUT - I talked to Matt at IMI - (HI-Torque) today 11-13-2012 - - He says ALL the Porsche starters they make DO NOT REQUIRE SHIMS - says that ALL Porsche are 1.3 inches from mounting flange to contact-point of ring gear teeth (my IMI from Pelican is part number 101N - (I see others on web, eBay, etc that do not carry the N suffix) -

Here's the fix for puting new rings on older 911's -

RIMCO VW does it all - $130 includes ring -

http://www.rimcovw.com/shipping-procedures/.

Damn :-(

Just a reminder to anyone reading this thread. My first ring gear had approx. 10 teeth sheared off using my original starter. The second ring gear sheared off the exact same way using the high torque starter. Both ring gears were only a few weeks old. The damage I experienced was definitely NOT caused by the starter.

http://forums.pelicanparts.com/uploa...1351848224.jpg

Wow!

fwiw - I talked to Matt at IMI - (HI-Torque) today 11-13-2012

- He says ALL the Porsche starters they make DO NOT REQUIRE SHIMS

- says that ALL Porsche are 1.3 inches from mounting flange to contact-point of ring gear teeth

(my IMI from Pelican is part number 101N - (I see others on web, eBay, etc that do not carry the N suffix) -

also says there is a "clone" being sold on eBay that is giving them fits - it is sold as a "hybrid"

,

Larry,

I have the IMI-101 which is the 1.2kW model of the starter. The IMI-101N is the 1.4kW model.

My high compression race motor turns over just fine with the 1.2kW model.

KEP sent back my pressure plate with the new KEP ring gear installed. Unfortunately, my race car won't run again until March or April so I won't be able to report back with any useful data until sometime after that.

Scott

UPDATE 11-16-2012 - (search my posts on other threads for more...)

- Kennedy Engineering (KEP) says that Bosch had a thin nose bearing & it breaks on engine kickbacks - then the pinion goes out of tolerance & chews

- I found that was exactly the problem - the Bosch hi-torq starter was the definite cause -

I am switching to an IMI HiTorque - on KEP's advice - from Pelican, number is 101N, and IMI says it does NOT require shims

meanwhile - the ring gear CAN BE REPLACED by RIMCO - $130 - just got mine back today

http://forums.pelicanparts.com/uploa...1353107057.jpg

Good grief, glad you fiundthe culprit. Geez just unbelievable.