Cam Tower Fit

[Jon944]

Hi All
I am working on my 86 944. It's been off the road for many years due to a persistent miss fire that I have still not been able to track down - tried many things. Alas I only get short periods of time to spend on it and they are often spaced far apart.

Anyway, had this thought that there might be a broken valve spring -> lazy valve -> poor combustion so pulled the cam tower - no sign of a broken spring as far as I can see, all have similar pressure when I try to compress them just a little so now am putting the tower back on.

I've read many posts here and the Clarke's Garage procedure which I am trying to follow.

I have 2 concerns - need some reassurance or advice.

1. WIth the tower off & upside down, lifters fitted (should be the matching ones but they did come out some time ago and memory fades...) when I turn the timing belt gear, some of the lifters seem to bind making it impossible to turn the cam. Some wiggling of the cam back and forth and the lifter eventually frees and the cam turns. Lifters were not well stored nor pre-soaked (just read about this). Lifters had some heavy grease applied to hold them in the tower during the reassembly. This does not feel right but I could equally imagine that there are different forces at work in the assembled condition. What should I expect in this condition - smooth operation of the cam and lifters (assuming I push them back in to their bores manually as the grease holds them up)?

2. Moving past item 1, I put the tower to the head. At TDC, 2 lifters protrude. Reading around, it sounds like a simple task to screw down the tower but I find that the 2 protruding lifters require 2 valves to be compressed before the bolts will even reach the head. For me this is not something I was able to physically do. In the end I used 2 longer M8 bolts in the manifold side holes as alignment guides and had to back the cam off to about 30-40 degrees before TDC to get the tower close enough for the bolts to reach and begin tightening. I still have a gap between the tower and head (stopped for dinner and contemplation) but I can't turn the cam to get back to TDC mark. The question is, should I expect to be able to fit the tower at TDC (meaning compressing 2 valves) or is the 30-40 rotation the usual route to getting the job started? Also, should I be able to rotate back to TDC with moderate force? This might be item #1 again....

Thanks for reading, any thoughts appreciated.

Jon

[89-944NA]

Let me get this straight, you couldn't get all the cam housing bolts to start in their respective holes, so you removed the cam housing and rotated the cam 30-40 degrees and put the housing back on? It is going to be tough, as you said, 2 lifters are protruding, and this is as it
should be.

Remove the cam housing and realign the timing marks, then put the housing back on the head. Put all the bolts in place, then use the other 13 bolts to draw the cam housing down just enough to get the remaining 2 bolts started. Once all the bolts have been started, snug down the housing then torque, following the clarks garage procedure.

[matty89]

and dont go to fast.... i whent to fast and one of the threads in the head came out .. had to TIME SERT one hole just my 2cents go slow a little at a time all bolt equal.

[Jon944]

Engage sheepish mode...
Thinking over the days work last night it suddenly came to me...
Ahem - lifters in upside down!

It's probably something one should "just know" - I can see a confirmation in the PCNA "Parts & Tech Ref" exploded diagram confirming my error.

Let's see if there's any damage done - heading out now.

On the plus side I can check the lifters for softness and putting that cam tower back should be a smoother ride this time around.

Doh.

Sorry for the noise & thanks for responses.

Jon

[Gawernator]

Sounds like something I would/will do!

[Jon944]

2 lifters damaged by cam.
Parts place closed for the holidays.
Lesson learnt.
Sigh...

[89-944NA]

Ouch, lifters for these cars are not cheap, somewhere in the $70 each range....solid side to cam, hollow side with the plunger to the valves.