[kwikt]

Just purchased a 92 968 6-speed and am in the process of checking the timing and tightening the balance belt which had about 1 inch of play. I got most of the info from the service manuel on this site(thanks). I took the starter off ... thinking I can see the tdc marks on the flywheel..... nope....... Is there an inspection cover or maybe does the cover on the bellhousing have to come off? Anyone have a picture where I can see where I need to be? I also took the valve cover off and am replacing the leaky seals( one of my spark plugs holes was filled to the top with oil).This is the only thing holding me up now. Next is thermostat, plugs, power steering hose. Thanks!



Kevin

92 968

72 911T/E

03 330i

01 Harley fatboy/ S&S kit

Partial Post: Please Login or Register to read the full post.

[sasilverbullet]

if the belts are still on, if you bring the camshaft to it's mark, then you can look at the flywheel and the marks will be obvious.



Most folks just line up the mark on the camshaft, put the flywheel lock in, and then do whatever needs to be done...I did it that way and all went well.

Partial Post: Please Login or Register to read the full post.

[rustech]

The hole that you check for TDC is on the top of the bellhousing. The manual calls for a mirror that you hang from the hood that allows you to see down behind the motor into the inspection port.



Remember that the camshaft pulley rotates twice for every one rotation of the crank, and so it only gives you 50% chance of TDC, so you must verify it by other means (piston one up, or tdc marks).



Good luck.

Partial Post: Please Login or Register to read the full post.

[kwikt]

[quote name='rustech' post='39776' date='Aug 11 2007, 10:25 PM']The hole that you check for TDC is on the top of the bellhousing. The manual calls for a mirror that you hang from the hood that allows you to see down behind the motor into the inspection port.



Remember that the camshaft pulley rotates twice for every one rotation of the crank, and so it only gives you 50% chance of TDC, so you must verify it by other means (piston one up, or tdc marks).



Good luck.[/quote]



No wonder...... I was looking underneath. Thanks for the info guys! Hopefully I'll have her running today.



Kevin

Partial Post: Please Login or Register to read the full post.

[sasilverbullet]

hmmm, I thought it was the other way around, two rotations of the crank to one of the cam?



If you're right, then how come when ever match up the cam markings, all the balance shafts line up also? Do they also do two per one revolution of the crank?



Another thought - why does it matter? If you line up the cam marks and lock the crankshaft, and replace the belts, what's the dif?



Inquiring minds want to know! <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" /> <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />

Partial Post: Please Login or Register to read the full post.

[rustech]

[quote name='sasilverbullet' post='39779' date='Aug 12 2007, 06:19 AM']hmmm, I thought it was the other way around, two rotations of the crank to one of the cam?



If you're right, then how come when ever match up the cam markings, all the balance shafts line up also? Do they also do two per one revolution of the crank?



Another thought - why does it matter? If you line up the cam marks and lock the crankshaft, and replace the belts, what's the dif?



Inquiring minds want to know! <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" /> <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />[/quote]



Dope! you're right. I forget who I was talking to that got me confused on the issue, it's been a couple years since I've been in there. Two rotations of the crank to one of the cam.



Regarding why it would matter would simply be that he wants to verify that his timing is correct; he needs to make sure the tdc marks line up.

Partial Post: Please Login or Register to read the full post.

[kwikt]

Never did find the tdc mark. So I made a unit that excepts a dial indicator and screwed it in #1 cylinder. The valve cover was off so I could see it was at tdc of compression stroke. It worked great. Lined my marks up and everthing is fine for now except..... I need an alternator now and still trying to get that da## snap ring out for my thermostat. BTW there are 2 strokes of tdc, compression stroke and valve overlap tdc.



Kevin

Partial Post: Please Login or Register to read the full post.

[rustech]

Make sure it is in fact the alternator and not just the voltage regulator. I have hardly ever heard of the actual alternator failing on these cars.



For the snapring, I had to ground hooks on the tips so that it wouldn't slip off. It makes it much easier.

Partial Post: Please Login or Register to read the full post.

[kwikt]

I changed the regulator today and it only shows 12.45 volts while idling and revving the engine doesn't change the volts either. So I'll probably order one tomorrow. Oh... and I finally got the thermostat snap ring off. Went over to the local Harbor Freight and picked up a set of assorted snap ring pliers($9 for the set of 6), one which happened to have a 90 degree bend, and no time flat ...out came the snap ring. It took me longer to jack the car up than to replace the thermostat!!!!!!Tomorrow new plug wires, cap, rotor and alternator. I hope that's it for now.



Kevin

Partial Post: Please Login or Register to read the full post.

[Scott Collins]

[quote name='kwikt' post='39872' date='Aug 13 2007, 06:04 PM']I changed the regulator today and it only shows 12.45 volts while idling and revving the engine doesn't change the volts either. So I'll probably order one tomorrow. Oh... and I finally got the thermostat snap ring off. Went over to the local Harbor Freight and picked up a set of assorted snap ring pliers($9 for the set of 6), one which happened to have a 90 degree bend, and no time flat ...out came the snap ring. It took me longer to jack the car up than to replace the thermostat!!!!!!Tomorrow new plug wires, cap, rotor and alternator. I hope that's it for now.



Kevin[/quote]



Kevin-



Just reading your post and hoping to contribute to the discussion. Sorry if you have moved on.



I had a similar problem with my '87 944 n/a. Car ran fine but I thought my alternator was going bad. Seemed like it would labor and the voltage would drop, according to the readings on my dash. I had the Princeton Porsche shop check this twice for me. (2nd time was no charge. Service manager was very cool.) They said that the alternator was fine, readings were good, and that it was probably just a "tired" diode.



Hope this helps.



-Scott

Partial Post: Please Login or Register to read the full post.

[kwikt]

Well Scott, just finished replacing my alterator today. I checked the volts and it read 13.4 so I guess I sort of needed one. BTW I bought it at the local Advance Auto for $110 plus a $105 core if you keep your old one....not a bad price! Oh also.... I never could find the marks for TDC.



Kevin

72 911T/E

92 968

95 Yamaha PW50 (for sale)

01 HD Fatboy

03 330i

07 F150

Partial Post: Please Login or Register to read the full post.

[Scott Collins]

[quote name='kwikt' post='41607' date='Sep 23 2007, 04:59 PM']Well Scott, just finished replacing my alterator today. I checked the volts and it read 13.4 so I guess I sort of needed one. BTW I bought it at the local Advance Auto for $110 plus a $105 core if you keep your old one....not a bad price! Oh also.... I never could find the marks for TDC.



Kevin

72 911T/E

92 968

95 Yamaha PW50 (for sale)

01 HD Fatboy

03 330i

07 F150[/quote]



Kevin,



Cool. It is great when you can find the culprit. $110 is a great price, from Advance? That's a surprise.



Check the DIY's for a post on Balance Belt Replacement - let me see if I can get the link...



http://www.968forums.com/index.php?act=Att...e=post&id=1



I am right in the middle of doing my belts and rollers, and found the above very helpful. It's an

outstanding write-up on replacing balance and timing belts, rollers, etc., and it includes a description

of how to get TDC. It helps to have a friend do this with you - one looks while one cranks - saves time and helps to have another set of eyes to validate what you are seeing, especially if it is your first time doing this "fun" job.



Cheers and good luck!



-Scott

Partial Post: Please Login or Register to read the full post.

[Ryan]

I went through this "where the hell is the tdc mark thing" and can tell ya it was all very confusing. The flywheel mark is viewed from the bottom of the car looking back from the front of the car. If you are under the car looking back at where the flywheel would be, there is a 3/4" plastic plug at the center front down low. Pull out the plug and shine in your light. There are 3 marks like "lll" and the center mark is the one used. When this mark is visable as well as the mark lining up on the cam gear and housing you are at TDC on #1. I stuck a long wire down the sparkplug hole to show me it was at the top of the stroke as well. Hope this helps as there are too many wrong locations discussed.

Partial Post: Please Login or Register to read the full post.

[kwikt]

Yes Ryan, I found the same plug to find tdc. I still lean towards a dial indicator though.



Kevin

Partial Post: Please Login or Register to read the full post.