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Rocker Cover holes. How many?

Rocker Cover holes. How many?

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SteveOS3

Original Poster:

424 posts

115 months

Wednesday 11th October
quotequote all
S3 2.9 V6

As part of the gearbox overhaul I've taken the n/s rocker cover off and see that there are 7 holes in the cover and 8 in the head. There looks to be a place for a hole in the cover, and there is a matching hole in the head, see below.

It's an alloy cover.

Is this normal?






Also, the bolts are of differing lengths, the corner ones have a section that extends beyond the threaded section; maybe to prevent overtightening?

I'd like to replace the bolts with stainless but not sure if I would need spreader plates as the current setup only has washers.
Thinking of getting these as per a link from RayTVR:

http://www.ebay.co.uk/itm/FORD-COLOGNE-V6-2-8-2-9-...


v8s4me

5,737 posts

143 months

Wednesday 11th October
quotequote all
The rocker cover gasket for the 2.9 has eight holes.

But stainless Allen bolts and spreader plates from HERE for the 2.9 only have seven bolts. I wonder if the supplier has used the wrong photo?

Not much help I'm afraid but I'm sure a 2.9 owner will be along shortly to clarify.

SteveOS3

Original Poster:

424 posts

115 months

Wednesday 11th October
quotequote all
Hmmm, picture shows 14 bolts but description says 16.

It also says that they won't fit the alloy cover but will fit the pressed steel. Maybe the pressed steel had 8 holes, my alloy cover has 7.




v8s4me

5,737 posts

143 months

Wednesday 11th October
quotequote all
It'll probably be because the alloy cover is thicker. So if you want the stainless spreaders maybe he can supply longer bolts for you to cut down.

Here's a picture of my 2.8 with the stainless spreader & bolt kit...


phillpot

13,362 posts

107 months

Wednesday 11th October
quotequote all
SteveOS3 said:
It's an alloy cover.
We know biggrin



SteveOS3 said:
Is this normal?
Those covers are not original to your car, they will have been taken from something like a 2.8 Sierra XR4i and someone has used a mish mash of bolts?
The top row of four are into alluminium and quite easy to strip, possible a longer bolt has been fitted to try and "find" some thread at the bottom of a stripped hole?
Whatever bolts you decide upon I'd strongly suggest you don't torque them up, I've seen threads stripped and gaskets squashed to nothing!
.......... I's all about "feel" wink

Use as they are or drill out the eighth hole.

Spreaders are to help prevent distortion to the original pressed steel covers, not necessary on cast alloy covers.

Looks like Ebay seller is using generic photo's or getting his 2.8 and 2.9's mixed up.


Genuine Ford (Motorcraft) gaskets , getting a bit hard to find these days, have little spacers in them to help prevent the gasket being over squashed. These are not required with the alloy covers because they don't distort and so clamp down far more evenly.





ETA. length?..... long enough but not too long!

I'd say you want about 15mm of thread once bolt has gone through washer, cover and gasket. Thread is M6,

Original bolts, with steel covers, would have had an unthreaded tip on the bolt, this makes them easier to get started, particularly in an mass production process with power tools









Edited by phillpot on Wednesday 11th October 14:23

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glenrobbo

8,996 posts

74 months

Wednesday 11th October
quotequote all
The answer is that the 2.8 heads have 7 holes in each, whereas the 2.9 heads have 8 holes.

Special spreader washers are required when using the original pressed steel rocker covers which are prone to distortion due to over-zealous tightening.
No need for them on the alloy rocker covers. The extra bolt length required for the alloy covers is minimal because the thick washers aren't required. It is perfectly ok to swap the screws for stainless. Allen cap head screws are easiest for access.

The original rocker covers are easily distorted by overtightening the screws, and so the genuine Motorcraft rocker gaskets were fitted with an alloy anti-crush sleeve in each hole to try to prevent this.
Rubber gaskets are available and although more expensive, can be re-used and are less likely to leak oil.

The 2.8 alloy cover in the OP's photo can easily be made into a 2.9 cover by simply drilling the missing hole in the blank lug. The two versions are otherwise identical.

HTH smile

SteveOS3

Original Poster:

424 posts

115 months

Wednesday 11th October
quotequote all
Cheers everyone.

I ordered gaskets from a few people online who had pictures showing the spacers but they turned out to be plain cork - I kept the plain cork set from Burton Power.

I'll drill out the blank tab and get some Allen cap bolts in M6 stainless.

That's the easy bit over with, tonight I'll be mainly dropping the diff' carrier to get the propshaft out. I hope there's enough give in the new rear diff' mount to drop the front far enough.

Thanks again,

Steve