Need an opinion

[IDGAF27]

I had a thread about non starting engine.With help of you guys ,I solved that problem - I start it. Thanks a lot. Here is the link to thread:won't start C2

Now I want you to share an opinion, knowledge what could be cause of it. Flywheel sensor failure wasn't electrical. Look at a pics. It was brushed with flywheel . So I am thinking what could of bin a cause. Want to prevent happening that in a future.
Can it be that flywheel has to big freeplay. What could cause that? Berings or clutch? Or I missed some sort of gasket when was installing sensor. But I am 100% positive there was none.

Please share your knowlidge and thoutghs.

[Oracle]

Maybe the flywheel is too soft? Do you remember if you car got the upgraded flywheel (LUK?)

[bazar01]

Was any previous work done on the flywheel and sensor that could have upset the gap setting between the flywheel and sensor?
How was the sensor bracket bolt to bell housing before removal? Was it loose?

[IDGAF27]

By looking through the sensors opening I can tell - flywheel is original as well as clutch pressure plate.
Sensor braket sat nicely in it's own place.

I am aware of crankshaft longitudial freeplay and other cars because of faillure of bearing, which causes crankshaft sensor being eaten by crank.
But is it posible for engine run smoothly w/out any knocking noise and have worn main crank bearings to alow flywheel move in ecliptical circle ? Am I assuming worse? Or can it be some weird flywheel deformation?or anything else...

Here are some more pics of sensor and it's bracket.

[IDGAF27]

Originally Posted by Oracle

Maybe the flywheel is too soft? Do you remember if you car got the upgraded flywheel (LUK?)

What you mean by being too soft?
My car is all original , no upgrades.

[IDGAF27]

Originally Posted by bazar01

Was any previous work done on the flywheel and sensor that could have upset the gap setting between the flywheel and sensor?
How was the sensor bracket bolt to bell housing before removal? Was it loose?

I don't think so there is much to do to upset gap. Sensors bracket sit on trany housing w/out possibility to be adjasted. So I think gap is about 1mm ? for the sensor to be able to read flywheel rotations.
If that was relacement sensor eaten like that I would alow possibility sensor being to long. But in my case, that was original sensor .

So what could be the case? Any opinion

[Oracle]

The 964-C2 1990 - 1992 came with the Flywheel "Fredenberg" sometime in 1992+ the new and revised part is from a different supplier "LUK", the new part no. is: 964.114.012.02
It is possible the starter ring gear is a little off so it's not spinning totally straight.
To read more about flywheel I recommend the 964 bible: Porsche 911 Enthusiast Companion by Adrian Streather, Page 190.

[IDGAF27]

Hello guys. Need opinion and help.

NEW SENSOR HAS GONE SOUTH- BRUSHED FACE . Flywheel did it.

Thanks for input, but don't tell me to buy a book or take car to a dealer or mechanic. I'll fix the problem eventualy and in that time I want to learn and understand more about a car I love.

BTW I did ordered books it just takes long time to get them. Please any thoughts?

[IDGAF27]

[QUOTE
It is possible the starter ring gear is a little off so it's not spinning totally straight.
.[/QUOTE]

I never had taken clutch nor flywheel ,of Porsche, off. But through the sensor opening I can see two toothed surfaces. One is for starter and one for sensor reading. distance between them close to an inch. so starter ring ,I assume, is the one with triangular teeth and sensor reading piece is square . for starter ring to be able to touch sensor it should be totally off and lose ,and make noise like bunch of bolts and nuts in an empty metal bucket.

Correct me if I wrong.

[ischmitz]

The gap of the sensor can be adjusted by loosening the two allen screws that mount the bracket to the case. Use a feeler gauge and adjust to factory clearance of 1mm +- 0.2mm gap. You can use a penny to check clearance. It has the correct thickness. And rotate the engine at least once to check every position of the flywheel.

There is no way the flywheel is tumbing in the case. If this was happening your engine would feel like a diesel tracktor. Maybe something got caught in the DME teeth? More likley the clearance was not adjusted properly.

Ingo

[bazar01]

You have to gap the new sensor properly as Ingo had stated.

Glue a 0.8 to 1 mm small washer on the tip of the new sensor and mount it on the bracket. You cannot use the old sensor because it's been scraped already.
Rotate the crank so the flywheel teeth is right on the sensor location then mount the bracket and push the sensor against the teeth. Lock down the sensor bracket.
Pull just the sensor out leaving the bracket on the case, then remove the washer and remount the sensor. Rotate the crank a few times to check.

Good luck

[IDGAF27]

Originally Posted by ischmitz

The gap of the sensor can be adjusted by loosening the two allen screws that mount the bracket to the case. Use a feeler gauge and adjust to factory clearance of 1mm +- 0.2mm gap. You can use a penny to check clearance. It has the correct thickness. And rotate the engine at least once to check every position of the flywheel.

There is no way the flywheel is tumbing in the case. If this was happening your engine would feel like a diesel tracktor. Maybe something got caught in the DME teeth? More likley the clearance was not adjusted properly.

Ingo

Thanks Ingo. I am leaning to a idea of "something stuck in a DME teeth".
It is third day in a row, I am trying to rotate flywheel to inspect it. Haven't gotten around yet
Is there any EZ technique to rotate it, cause I am using flat screwdriver as elbow to rotate flywheel and it take so much effort. I tried planting socket on crank's pulley's nut, but then I can't squeeze ratchet in there to rotate engine EZ.

[IDGAF27]

Originally Posted by bazar01

You have to gap the new sensor properly as Ingo had stated.

Glue a 0.8 to 1 mm small washer on the tip of the new sensor and mount it on the bracket. You cannot use the old sensor because it's been scraped already.
Rotate the crank so the flywheel teeth is right on the sensor location then mount the bracket and push the sensor against the teeth. Lock down the sensor bracket.
Pull just the sensor out leaving the bracket on the case, then remove the washer and remount the sensor. Rotate the crank a few times to check.

Good luck

Thanks.
I don't think so bracket it self can be adjusted. Look at picture above. Two brackets holes totally circle , it doesn't give much room for adjustment.
I thought , might I missed any sort of gasket between bracket and sensor?

[bazar01]

The manual says it can be adjusted.
We are only talking of 0.8 - 1.2mm.

[IDGAF27]

Originally Posted by bazar01

The manual says it can be adjusted.
We are only talking of 0.8 - 1.2mm.

Any tricks how to rotate flywheel by hand except pushing teeth by teeth?
I don't want to put new sensor before I have inspected flywheel. Those sensors cost a bit
Is there any special tool/wrench to rotate crank with engine in a bay?

[bazar01]

I use the alternator/fan shaft with the triple square tool inserted in the bolt head and a ratchet handle while pushing down on the alternator belt to rotate the crank clockwise.

What you can do is put a mark on the tip of the worn sensor with a blue or black marker and put it back in and set it as close to the teeth without touching and rotate the crank a few times, pull it out and check for scraping instead of manually inspecting the teeth one by one for any burrs or raised areas.

[ischmitz]

The easiest way to rotate the engine is to use a remote starter. These can be bought for 15 - 20$ and make tasks like this a breeze. Also extremely handy for valve adjustments.

http://www.google.com/products?hl=en&rlz=1G1GGLQ_ENUS279&q=remote+starter+tool&um=1&ie=UTF-8&sa=X&oi=product_result_group&resnum=1&ct=title

Ingo

[IDGAF27]

Originally Posted by ischmitz

The easiest way to rotate the engine is to use a remote starter. These can be bought for 15 - 20$ and make tasks like this a breeze. Also extremely handy for valve adjustments.

http://www.google.com/products?hl=en&rlz=1G1GGLQ_ENUS279&q=remote+starter+tool&um=1&ie=UTF-8&sa=X&oi=product_result_group&resnum=1&ct=title

Ingo

Ingo you are DA MEN ! thanks. Bought remote starter - WOW, I did rotate and inspect flywheel in 10min.
what's an odds of little rock getting stock in flywheel teeth gap? I got one.
As I said and read a lot about flywheel sensor adjustment , there is not much play to adjust, but did my best and wroom-wroom is the best sound ever.

thanks for all the help putting my baby back on a road. Sad part is have to sell it now.
Good part is - I BOUGHT 1986 911 TURBO. That is the only reason i am selling it, or i just could live in a dog house.....