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[Barnes]

Hi all,

I have just rebuilt a 63 750cc interceptor engine, the pistons and bores were still standard size, but when the heads were assembled with the head gasket the left hand piston hits the head gasket, it just clips it and will go past, but I am unsure why it is hitting only on the left unit.

Any advice would be greatly appreciated.

Thanks
Ed

[Dennis C]

Hi Barnes
I had a similar problem with my 59 Super Meteor but on both pistons.
The cause was the original head gaskets are cut on a taper round the inside and only fit one way up but the new gaskets are cut straight and not very accurately, carful trimming of the new gaskets cured the problem.

[Mark M]

Barnes, need to know if Cross rings (like piston rings) or conventional gaskets? Also, was it running before rebuild? REgards Mark. (Mk 1&2)

[Norm]

Mark I don't think any of the 750's had a gasket they were all cross rings, correct? but anything is possible you have those 700 VAX Inters , they probably have gaskets and then we have this 63 Super Connie out here, removable cam caps ( Connie only), late Connie rear guard but with Inter barrels and heads. Anything is possible

[Barnes]

Hi.

Thanks for the replies, it has the cross rings fitted, as to the engines history I have no idea I have rebuilt it for a mate, i think it came from America in the container that hitchcocks brought, they have been extremely helpfull in the rebuilding of the engine. It is just the last few details.

Dennis can you tell me how you managed to trim them, was it on a grinder or file. Will the engine run with it like this or do I need to sort it before starting.

Cheers
Ed

[Dennis C]

Hi Barnes
I am a bit confused now, Norm is absolutely correct here, the Mk1 Inters all used a Torrington ring to seal the head barrel joint and don't have a gasket for the piston to touch.
I think more information is needed, and no don't try running it as it is.

[Barnes]

Hi Dennis,

Yes it uses the Torrington ring, and it is this that the piston is hitting, without the ring and just the head it turns over fine, but as soon as I put the ring in and torque the head down the piston nips the ring.

It will go past this point but with some pressure. I was wondering if maybe the cylinder is worn and the ring is sitting too low in the groove, and it needs a +.20 ring inserting to lift it clear of the piston.

Cheers
Ed

[big al]

just a thought would it be possible to put an extra gasket on the cylinder base thus raising the cylinder up a few thou. May be some one can comment on this. the idea might not be any good and it might not work its just a thought
Looking forward to your comments alan

[Dennis C]

Hi Barnes
I have a Super Meteor and my Son has a Constellation both of which I now know inside out, but I have no experience of the Inter.

I am sure one of our resident Inter experts will be along shortly to advise.

[Mark M]

Barnes, this is why I asked whether it was Cross rings not a head gasket! (When referring to these items in the context of Interceptors they are referred to as Cross rings, made for RE by the Cross Engineering Company of Bath, and still in business by the way!) The Interceptor Owners Group,(come and join us at http://groups.yahoo.com/group/RE_Interceptor/ ), have had a few examples of poorly fitting rings, indeed I had the self same problem myself on my 1966 Mk1 last year. The rings should normally be replaced in oversizes to match the rebore, it sounds like you have at least 1 wrong ring. Hitchcocks should be able to help. The rings H's supply are made by a different process than the originals which may be where the problem lies. Do not attempt to alter the end gap, this is critical during manufacture! REgards, Mark