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ES2 Valve Spring issue

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My es2 has started to make a bit of top end noise, certainly more than it did so I wipped off the head this morning and think I found the culprit the edge of the valve Spring/ cap has been hitting the inside of the rocker box. I can only assume that the Spring is slightly too big orthe cap too lose? Any thoughts ?

 photo image_zpsj0ewanfe.jpeg Cheers Dan

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Dan, many years ago a valve guide came loose in the Alfin head of my 19S. In that case the engine lost some compression but still ran. I wonder if your valve/spring assy is wobbling enough to cause those marks? You will have to remove the springs to check out that possibility.

Cheers, Ian McD

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I've done that, they seemed ok but the springs are a bit wider than the cap, the guy I bought it off has used a multitude of parts so it may be that the springs are too wide, the seat is certainly off a different model it has been filed to make it fit over the wider valve guide. A new set of springs and caps might do the job, I'll see what's about tomorrow!

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Have you checked for valve seat recession? The valves sink into the seats. Unleaded fuel is said to cause this. It used to plague BMW boxer engines in the late 70s or early 80s.

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My ES2 did exactly the same. Valve seat recession was the cause, new valve seats moved the valve assembly further into the head and further away from the rocker box.

Good luck tomorrow

Andy

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Thanks I'm not sure it's that, I've had New valves, new seat on one side and new guides, the other seat was ok. the length of the valve was within the spec quoted by Mike Pemberton, so don't think it's that. The sides of the box are straight there, it's hard to see how a shorter valve above the guide would move the valve gear away?

I thought valve seat regression caused the rocker arm to hit the top of the rocker box?

Dan

 



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