Not_Sure

I've read quite a bit, but i tired of looking at the computer screen.

can anyone clarify:
On the 944/928 the cam tensioner can be removed with out removing the cams, can this be done on the 68?

also, Does the chain need to be replaced? 944/28 say it does NOT, and that a new chain could cause accelerated wear on the cam gears.

lastly to loctite or non the tensioner bolts?

H.F.B.

On a 968 you can't remove the cam tensioner, aka variocam, without removing the cams. Try searching 968 variocam replacement...🤫

Afaik, Porsche says the chain does not need to be replaced. But I did without any issues.

No loctite on tensioner bolts needed, just the proper tightening torque.

Zirconocene

These things come in waves, it seems, but from what I've read there was a point in time where it was all the rage to change the chains in the 928s (the 32V engines, so very related to what you're asking about) to the IWIS brand product. It's not clear to me what was driving this among the wrenching community but maybe that gives you a couple more search terms.

I'm now interested to go back and remember what was going on so if I can dig something up, I'll post it.

Cheers

Not_Sure

Ok I got the cams out and the tensioner seperated. However apparently the check valve doesn't have a spring! What would this have affected? Im sure I didn't lose it as I was really careful and waiting for it to pop out, and it never did, but when I was compressing the tensioner it popped up enough for me to pull it out, and I expected a spring to fall out but nope it was missing!
so where Can i get a spring?

Im assuming this means the tensioner/pads were probably replaced at some point then?

also is there any difference between the new and old pads? Will the New tan ones turn brown over time? I noticed the new pads had a "B" stamped in them, but one of the old ones had an "A" and one had a "B"

and lastly, why do I need to "test the" Tensioner with the special pressurizing tool?? what happens if I dont?

Not_Sure

any one got any input? trying to figure out if im safe to put this back together

jsheiry

Not sure about all the A and B codes but if you have any wear lines/marks in the pads then replace as they are cheap and if it were me I would replace even if not visually worn because they do get brittle with age and as I said they are cheap and at this point of dis-assembly and effort level I would replace to satisfy the compulsive "while your in there dis-order" that so many suffer from including me.

I may have a spring in an old vario cam unit that came out of a salvaged motor from fire, will check this weekend.

The pressure tool your referring too I believe is not necessarily for testing the vario cam unit but for assisting to setting up the timing of the cams and simulating oil pressure on the vario cam unit whilst turning cams and observing valve movement etc...

Not_Sure

Ok I locked my timing down, does that mean I can skip it?

thomasmryan

If you locked the existing cam timing by using longer bolts at the rotor button BEFORE you loosened the exhaust cam cog bolt, you should be good.

H.F.B.

Check this links
https://rennlist.com/forums/968-foru...l#post15905644

https://rennlist.com/forums/968-foru...am-timing.html

👆Hope this helps. 🙂🍿

Not_Sure

Ok Im not sure whats going on here.
So the check valve seems to be spring loaded, despite there being no spring in the bore
heres a clip of the check ball working,
and the under side of it. maybe its a newer version?