Dean_Fuller

I am replacing the timing belt on my89. Using Pirtles write up. He states that at TDC the notches line up on cam gear and back plate...and mine do ( see first pic). At this point his instructions say to turn crank from TDC to 45 deg mark clockwise. When I do this my cam lines up in the second pic like so. I added a light black mark on cam at mar on back plate. The Porsche dealer did the last TB in 2002 and you can plainly see their ref mark in red DIRECTLY across on the cam gear. This mark WOULD line up IF the rotation clockwise from TDC to 45 degs included one full rotation past TDC.

Can some one PLEASE verify Pirtles directions of TDC directly to 45 degs. Either Im not doing this right or the Porsche dealer has one rotation extra....how would it run?
Am I mis-reading Pirtles directions???

Leon Speed

Dean, the crank makes two rotations for every one cam rotation. I don't see a problem, just that your cam timing might be off a degree or so. Do you have Porken's timing tool?

Dean_Fuller

I'm confused. From TDC clockwise directly to 45 degs is not a full rotation. If the instructions read rotate one full then to 45 degs my marks would line up with the Porsche dealer marks.....Their marks have me puzzled. I am not removing the cam gears...they look good so no need for timing tool right?...or am I wrong on that?
I am putting Ken's tensioner on though.

worf928

As long as the crank is at 45 degrees you are fine. It doesn't matter if you are on the intake or exhaust stroke.

That said, I usually rotate the crank through the full rotation and on to 45 degrees like the dealer apparently did. Mark the cam gear position before you remove the belt - the gears like to jump from the pressure on the cams.

Dean_Fuller

Thanks guys....I feel better....Im back at it!

ZEUS+

Like Dave said "the cam gears like to jump".
https://rennlist.com/forums/928-forum/428496-locking-cams-for-tbelt-replacement-and-battery-saver.html

Leon Speed

Make sure to check the condition of the cam gears once you have the belt off.

Mrmerlin

Dean to do this rotate the crank to TDC then go 1 and 4/5 ths of turns till the 45 is at the mark the cams will be about 1 inch from their marks ,(the cams will have a tendency to jump, the right cam likes to go CCW and the left likes to go CW once the belt is removed,) add some red paint to the new 45 deg mark on your cams, if the dealer did this the way i am suggesting then the dealer marks should line up.
From your picture you need to go another full turn.
To adjust (reposition the cams if they move)the cams remove the rotors and you will see 2 nut looking parts one is the hold down bolt (the smaller one) and the larger one is meant to turn the cams 30mm IIRC, turn the larger nut to get your marks in the correct place, once the belt is on and tensioned and the crank has been turned and the timing marks verified then install the rotors. It goes without saying that if any of the pulleys that the belt runs on are shiny polished then they should be replaced, pay careful attention to the oil pump gear it should have a dull finish on it as well as the cams To tell if your crank is at the 45 degree mark the keyway will be pointed to the 3 O clock position facing the engine and the damper can be read while facing the engine

Dean_Fuller

thanks guys...

Dean_Fuller

Its apart....will start reassembly Sunday...its beer thirty.
I think the cam gears and oil pump gear are fine to reuse. What do you think? I see little if any wear and very Little discoloration even.

Their never pretty in this condition. BTW...lots more work than the 16V I did last month.

marton

Gears look OK; is that oil coming from the oil pump?

Marton

Leon Speed

Looks like cooling fluid from removing the cooling hoses. Yeah, gears are starting to shine but I would leave those on.

Dean_Fuller

I have a serious power steering leak under the reservoir. Looks like the hoses are leaking. I know the oil pan needs doing. Not sure about the pump leaking. What the best way to get the crud off? Did just spill more coolant when the WP came off.

Mrmerlin

well now is the time to replace the PS resivour, the factory curved line and the short hose to the resivour (This gets the crimp cut off with a dremel),

You should also consider cleaning the oil pump area if the pump looks like its leaking then the seals should be replaced, that means the front radial seal, the big O ring and the 3 O rings on the bolts, also consider replacing the front main seal , check this for leaks.
The pulleys all look good, so can be reused.
When filling the tensioner ( you are rebuilding it ) I would suggest to use some STP instead of the thinner oils, ( thew thicker oil will not leak out as fast)

Rebuilding the tensioner includes removing the tensioner from the block replacing the gasket, replacing the Thin O ring and replacing the Rubber boot.

On the boot, Orient the inner clamp so that the open end is facing up IE its at the higest point of the tensioner, this will help to prevent leaks ,the outer clamp is best positiond at the 11 O clock area, test the tensioner to the front cover to make sure its not hitting before you crimp it.

The STP can be installed with a visene bottle that has had the tip enlarged to 1/8 in drill bit it .

Remove both bleeders and fill the tensioner after you have set the tension on the belt.
Fill from the hole futhest from the crank, using this botlle will also help to prevent over pressurising the tensioner and thus blowing out the iiner clamping ring BTDT

Dean_Fuller

Thanks Merlin...I'm not rebuilding the tensioner. I have Ken's tensioner I am using so one less oil filled problem area and I am told...no reason to check tension on belt! I will do some cleaning but it looks much cleaner behind oil pump gear.