Cylinder heads refitting

[shyster]

Hi, just replaced piston rings and refitted pistons and i wanted peoples opinions on the best way to refit heads. Last time I fitted left first then right head, THEN the manifold. This was quite difficult to do and required shimming up with various size gaskets to get the best fit, and in the end I still had a very slight weep from one side.
The manual states to loosely fit the manifold to the heads FIRST, then tighten up left head, then right.
Is this a better way to do it? I just can't see how the heads will be properly torqued down if there is a great lump of inlet manifold bolted to the other head thus preventing the first head from seating correctly.
Opinions?

[V Mad]

Unless I am mistaken, I think you have misread the procedure. The idea is to use the inlet manifold to pull the heads into line with it. To do this, tighten down one head only; then tighten down the inlet manifold to pull the other head into position; then finally tighten the head.

[dasadrew]

Engine Training Notes:

loosely fit Left head to block
tighten LH Head to block
loosely fit Manifold to LH Head
loosely fit RH head to block
loosely fit Manifold to RH Head
tighten Manifold to LH Head
tighten Manifold to RH Head
tighten RH Head to Block

[flying farmer]

Personally, I always tighten down the heads first, then fit the manifold. Biggest problem is that when the heads have been skimmed the manifold becomes too wide to fit easily and I always worry that it will prevent the heads from seating down.
It can be a pain to get the manifold to fit properly, I tend to use a coarse file to remove material from the manifold, but when it is done the manifold gaskets are usualy ok.
I have had problems caused by the heads not being skimmed flat, and leaving a bigger gap at the bottom of the manifold seating face resulting in the gaskets blowing out of the rear waterways. After this happened twice in a couple of years I filed the manifold to fit and it cured the problem
Neil

[Peter]

I would agree with Neil, fit and torque the heads first then sort out the manifold. Manifold leaks are a pain but head gasket ones are worse. The manifold should be removable once assembled without lossening the heads, so I'd fit it last - I always use gaskets with silicone sealent on both sides. To fit the heads cut down two old studs to fit in the short bolt holes these will then hold gasket and head in place whilst you fit the studs and bolts.

Regards,

Peter

[Bob Heritage]

The idea of fitting the inlet manifold as you go is to keep the heads parallel. You could waste a set of head gaskets if you have to slacken them off again.

[V Mad]

The idea of fitting the inlet manifold as you go is to keep the heads parallel. You could waste a set of head gaskets if you have to slacken them off again.

Spot on Bob.

[GDPR]

But not the way it was done in the workshop - anyone can quote from a manual, but reality is different and I and others did/do it the way Neil does professionally

[Bob Heritage]

Good to have you back Russ

[drek1]

will i be encountering any problems when i refit my intake manifold as i have removed it to do the waterpump????
del..

hi kryten

[STAG1973]

will i be encountering any problems when i refit my intake manifold as i have removed it to do the waterpump????
del..

hi kryten

Just removing the manifold you will be ok.

When i did my HG`S i fitted the manifold after torquing down the head bolts it was a bit fiddly but went on ok with no leaks.

Cheers
Adrian

[Kevin Garrod]

It might be worth getting the holes helicoiled, they have been known to strip. But as the heads aren't off I would just give it a go with my fingers crossed!