Strange noises in the engine

[Timj]

Hoping some of the engine gurus can help with this one. Standard 1977 2.25 4 cylinder Petrol engine. Had a head gasket give up on a trip on the weekend between cylinders 3 & 4. The rest of the gasket seemed fine. I have replace the gasket and put everything back together only to have a strange knocking noise happening. It is not consistent, if I turn the engine off and restart it will usually not be there, then if I rev it up it will come back and stay until the engine is turned off again. I have linked to a video that is really only useful for the sound track of when the noise starts. The engine is idling ok then given a rev and still ok, another rev and noises start. I am thinking it may be a sticking valve or something like that, tappets are adjusted correctly as far as I can tell.

https://www.youtube.com/watch?v=0c8gpQOi6gE

Any help appreciated :)

Thanks,

TimJ.

[Killer]

Tim, it is not as simple as a leaking manifold is it?

Cheers, Mick.

[Timj]

Hi Mick,

I don't think so. I never actually took the manifolds off, I just lifted the head off with manifolds still attached. Also it runs fine without rattling sometimes which I would not expect with something like a manifold leak.

Thanks,

Tim.

[Timj]

Well, found the problem. One of the pushrods was not perfectly seated in the cup at the bottom. Tappet was adjusted correctly but needed quite a bit more adjustment once the pushrod was properly in place. Now running fine.

TimJ.

[Killer]

Good to hear you found the issue Tim.

Cheers, Mick.

[Ozdunc]

How did you tell the pushrod was out?

[Timj]

The adjuster was sticking up through the lock nut more than the others. I had to back the adjuster right off and then could wiggle the rod and it dropped down a little into place.

TimJ.