Rocker problem

[lee_rob]

Hey guys

Just had my head professionally rebuilt only to find my rocker cover won't now fit on. This is because newer type rocker arms have been fitted which have clamp bolts on them and these foul on the tapered cover. Anyone else had this problem and know how to get around it??

Lee

[ian judd]

How about fitting a really thick cam cover gasket to lift it up a bit? (You could experiment with some card first)

[lee_rob]

The cover fouls far too low down for a thick gasket to be of any use, we are talking the cover being about a good inch from the head face

[lee_rob]

Another thought, as I have a later 31 engine fitted to my car, which I think is the engine from the Family 8, did the rocker covers differ as from some pictures I have found the earlier OHC minor covers look different from the later family 8 ones.

[Ian Grace]

Lee,

This is a known problem with J2 rocker fingers which your rebuilder has fitted because new M Type/Minor fingers are not available. They fit inside the MG alloy rocker covers, but no t the Minor one. You can grind metal off the clamp bolt heads or bend the cam cover out a bit, or fit an alloy cover. The first option usually works.

[lee_rob]

Ian,

Hmm I guess they will have to be ground back then, not sure if I do it myself I will disturb the valve timing that has been set up by removing the bolt for grinding or if they can be put back easily??

Lee

[Ian Grace]

You should be OK as long as you don't rotate the eccentric bush in the finger while the bolt is out.

[Sam Christie]

Why not use an MG M-type/J2 cover if you can find one?

[lee_rob]

Ok am I also right in thinking that these should still be set up with the eccentric bush towards the cam or is this not as critical on the J type fingers?

[lee_rob]

Why not use an MG M-type/J2 cover if you can find one?

That is an option I guess but I would have to find one and also I guess they would be expensive being M type bits

[Ian Grace]

Ok am I also right in thinking that these should still be set up with the eccentric bush towards the cam or is this not as critical on the J type fingers?

Yes, as with the Minor fingers, you need the thick part of the bush towards the cam, otherwise the oilways don't connect. This has the effect of offsetting the finger inboard, actually helping the clearance with respect to the cam cover.

Check out the Tech Topics in M 103, which you can find in the Members' Area.

[ian judd]

Actually, it's only with the J type followers that the position is critical. With Minor and M the follower is fully enclosed so the oil will always find its way round. The J has a gap where the pinch bolt is. I think the MG cover can be bought new but I don't know how much they are. S + V probably do them.

[Ian Grace]

Here's the Minor rocker finger arrangement from the handbook, showing the arc within which the eccentric must be positioned in order to maintain oil to the finger.

[Ronald]

We have these new type fingers on MT now, and the engine came back with a minor cover fitted.... so i can only assume he ground the bolts back to gain clearance....... although, knowing him he most likely sourced shallower headed bolts!

[lee_rob]

We have these new type fingers on MT now, and the engine came back with a minor cover fitted.... so i can only assume he ground the bolts back to gain clearance....... although, knowing him he most likely sourced shallower headed bolts!

Who did your head?