Noise from 325 engine

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sshinx1
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Location: Newry, Ireland

Wed Oct 04, 2006 9:57 am

Hello all,

here's the story, my sport slipped the timing and broke a valve which in turn damaged the head and one piston, so replaced the damaged piston and came across a complete head from a low milegage 325 Automatic, so i put the new head on with a new head gasket new timing belt, new plugs etc giving a complete service, built her all up again and cranked the engine over, which in turn she more or less started first time, but when she started there was and still is a loud noise coming from the top of the engine which sounds like a rattle or tappets, but i dont think its tappets as it is quite loud, the engine seems healthy enough, but i am afraid to rev or let the engine run too long because of the noise, the head came off a car that was lying up with the bonnet off but engine was covered. Any help would greatly appreciated to try and rectify this problem.

Shane.
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Wed Oct 04, 2006 12:55 pm

Very tricky to diagnose remotely.

First I'd whip the cam cover off and check all valve clearances again, and visually inspect all valve springs etc. A compression test may be useful - although you have at least one new ringed piston (did you re-hone the bore?) which will need bedding in (by a proper drive - don't run in anything like a fairy, as fairys know little about modern engines).

Do clearances cold.
Make sure plugs are in (not tight - just actually all the way in), head is on with new stretch bolts, manifolds are tight.

If all that fails to show anything up, try listening down a long screwdriver to see where the rattle is coming from, and run without the cam cover (dust free environment only!!!) to check the cam is being lubed OK.

Bear in mind extended idling is not good for new cams (if you fitted one).
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gcorky
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Wed Oct 04, 2006 6:31 pm

is the cam running dry-,check with cover off to view spray bar?
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sshinx1
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Thu Oct 05, 2006 9:24 am

took another look last night and it defintely seems like the tappets, took the rocker cover off checked all, could not see anything that could be a problem, seems to be plenty of oil around the valves so im assuming the spray bar is working ok? i am going to set the tappets and see what difference this will make, the head that i put on would have not being used for at least two years, so maybe parts within the head have become ceased etc and may need to be freed up or replaced.
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