OK Dean .....firstly is this the engine i helped with for alex ? if so here goes ..........
\\\\\\\\\ { A few things ...
1. how well did the camshaft fit, was there any sideways movement when fitted,
2, did you put a duplex (twin chain) timing gear on, if so did you remove the tabs from the inside of the timing chain cover
3 how well did the followers fit, did you test each one and check
how well they fitted.
4,what was the trush washer at the end of the camshaft like, (the triangle thing with 3 bolts) was it badly worn, was it replaced
5, are the push rods hitting the side of the holes they go through in the head and block
6, was there any bad wear marks or scores in the piston bores
7, is it the same head that came with the engine or a different one, may be worth trying a new head, but thats a long shot,as it seems to be more on the block that the head but worth a try
if you have covered all them the only other thing i can think is that it could be mains and big ends,or may be cam bearings, but only at the first stages of going,
because if they have gone it would do it at idle as well as when the revs are lifted, but this seems to be only doing it when the reves are lifted,idle is quite, plus only at 1 end?
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to answer a few of your questions ,here goes .
1) no sideways slap
2) No replaced with normal simplex which came out
3) Followers were a good fit no play and free movement
4) old thrust was worn badly and subsequently replaced with another better one within tolelrance spec
5) Push rods located correctly and no interference .
6) no obvious or bad signs of heavy wear just normal polishing of bore.
7) couldnt tell you engine came to workshops without one fitted ?
The only thing i could specualte on this is it could be cam bearings ,i was going to fit the "other cam" but cant remember if i swerved it owing to its heavy pitting on the cam bearing face or not ? ive got a feeling i fitted the origional or an alternative with less significant wear on it ,this was a choice of two evils at the time with no other choice owing to money and time.
the bearings in the block were in good order so can not see immediate wear causing this much noise so quick .
i would sugest draining the oil to see if there is any debris in the oil to determin if its a bearing issue or otherwise .
engine was re- assembled here with austin rover workshop manual and tolerances were also adhered to including re facing the crank tail as someone had animaled it sometime in its recent past .many engines have passe this workshop with the relevant success too .
I am wondering if this is perhaps a bearing issue ,where the ignition is removed from the particular cylinder it stops so taking the ignite percussion from the cylinder tells me this cylinder may have an issue with either the small end (piston end of piston rod) or perhaps big end or crank cap on this end but as dean says unlikely as you would hear the crank and big's all the time .
awaiting your findings on the cylinder compression test could be as simple as head gasket !.
we can all speculate on a forum all day but untill it is seen and tested in someones workshop no one will know .
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