xpost - timing belt and tdc alignment problem
10-10-2010, 04:40 PM
#16
Burning Brakes
Thread Starter
10-10-2010, 06:05 PM
#17
Rennlist Member
the thing is every 944 ive had ran at the center horzontal bar on the temp gauge- whether being driven easy or beaten on the track. If yours was running less than that, maybe the timing was retarded and you were not getting full advance. Now its running better because the timing is right and your temp is finally good.
10-11-2010, 03:58 PM
#18
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I did belts last spring and went through the same mark issues. This ain't rocket science. Saw a slight offset between pre / post work positions. With cam tower on mark fly wheel was off ~ 3/8" at groove on bottom. Flywheel on top top timing mark, cam tower looked off ~1/2 tooth. Tried 3 belts - First was new old stock (Porsche OEM), refitted old belt to check (same offset), went with new Gates (Porsche OEM supplier I think). Same slight offset. Cam shaft revolve at 1/2 speed of crank shaft (by design). No shifting of belt / cog would bring anything in better alignment, so I just went with it (manual engine rotation check first always). Engine ran fine.
If you've over tightened, that can cause whine. I suppose if you've under-tensioned, there could be slipping at the water pump. It would be very hard to close the cover up with the belt that loose. I used the Arnnworx tool set for tension adjustment. A great set up once you get the hang of it. I had my belt at the tight edge of range, very very slight whine (much much less than Arrnworx vid) until engine warmed up for about a month - Gone Now.
Porsche water pumps are a weak link. Over tension will shorten bearing life. If your car sounds like Arrnworx - probably need to recheck tension.
If you've over tightened, that can cause whine. I suppose if you've under-tensioned, there could be slipping at the water pump. It would be very hard to close the cover up with the belt that loose. I used the Arnnworx tool set for tension adjustment. A great set up once you get the hang of it. I had my belt at the tight edge of range, very very slight whine (much much less than Arrnworx vid) until engine warmed up for about a month - Gone Now.
Porsche water pumps are a weak link. Over tension will shorten bearing life. If your car sounds like Arrnworx - probably need to recheck tension.
10-11-2010, 07:33 PM
#20
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Thanks - Looks best from a distance 
~115K miles - First owner left it sit in a garage for almost 9 years and put 110K of the 115K miles on it. Second owner did some work but abandoned the effort (bought new Lotus). I've done what winds up becoming due, clutch, belts, etc. Fighting DME wiring now. But there is a reason many list 944's as their "daily drivers". These puppies just keep rolling. Had an early Boxster for 5 years. This old girl has more class and more axx.
Fantastic Duck - My need for 2 wheel speed is an R1. Its fast but only Italians know how to go round corners on 2 wheels
~115K miles - First owner left it sit in a garage for almost 9 years and put 110K of the 115K miles on it. Second owner did some work but abandoned the effort (bought new Lotus). I've done what winds up becoming due, clutch, belts, etc. Fighting DME wiring now. But there is a reason many list 944's as their "daily drivers". These puppies just keep rolling. Had an early Boxster for 5 years. This old girl has more class and more axx. Fantastic Duck - My need for 2 wheel speed is an R1. Its fast but only Italians know how to go round corners on 2 wheels
