Engine re-build... strange noises!

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Engine re-build... strange noises!

Postby Quothcorvus » Mon Feb 24, 2020 9:02 am

Hi, I would be grateful for some advice concerning a bit of an unexpected noise coming from an engine currently being re-built

Its a '59, and we have replaced both the cams with new, and new pushrods. As the engine is turned over by hand, there is a clicking sound as both inlet cam lobes go over top (fully open). There is no sound coming from the exhaust side of things. The tappet clearances have been set correctly and checked, and the springs are not getting bound.

I'd be grateful for any help/suggestions what might be causing the noise, thank you.
TTFN

Jon.

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Re: Engine re-build... strange noises!

Postby MalcW » Mon Feb 24, 2020 10:12 am

Do you mean clicking as in a 'click click click' sound, or a single click? Can you identify whether it is coming from the valve or the cam end? Putting your ear against the handle of a long screwdriver with pressing the blade against various points on the engine while it is turned over can sometimes help to locate sounds.

Malc

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Re: Engine re-build... strange noises!

Postby mdt-son » Mon Feb 24, 2020 11:08 am

MalcW, going by the OP's description this has to be a single click.

Q, this is a long shot but I'd inspect cam follower bushes and valve guides for wear. Some parts appear to be moving laterally while under load ...

-Knut

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Re: Engine re-build... strange noises!

Postby 1608 » Mon Feb 24, 2020 11:03 pm

You are aware that '59 push-rods are a different length to '60 onwards rods and not that easily come-by Just a long shot!

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Re: Engine re-build... strange noises!

Postby Duncan » Mon Feb 24, 2020 11:04 pm

Possibly excessive endfloat on the camshafts if you have not already checked it, not much to strip down to check just see how much play you can feel on the timing gear.

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Re: Engine re-build... strange noises!

Postby G15 Roy » Tue Feb 25, 2020 7:47 am

1608 wrote:You are aware that '59 push-rods are a different length to '60 onwards rods and not that easily come-by Just a long shot!


Now in stock at Kettering.
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Re: Engine re-build... strange noises!

Postby Quothcorvus » Wed Feb 26, 2020 10:30 am

Hi everyone, thank you for taking the time to reply to my query.

In answer to the posts..

Malc, its a single click coming from the cam end, as it goes over the lobe, inlet cam only, but on both lobes. There is no noise from the exhaust cams.

Knut- cam followers were replaced less than 1000 miles ago, and were not showing any signs of wear. We'll double check value guides- I think they were checked for wear, but will make sure

1068- Yes, I was, thank you. I ordered a new set of pushrods "59 only" from Kettering.

Duncan, we will double check end float as well.

Thanks all!
TTFN

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Re: Engine re-build... strange noises!

Postby Expat » Wed Feb 26, 2020 3:37 pm

Different animal admittedly but it was excessive cam end float causing the ‘clack’ on my G3. The lobe contacts the tappet off center, turning it slightly to even out wear, thus pushing the camshaft axially sideways.

Apologies if I’m preaching to the converted.

Steve
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Re: Engine re-build... strange noises!

Postby Quothcorvus » Wed Feb 26, 2020 4:01 pm

That fine Steve, thank you. Its been suggested cam end float could be the issue, which we are going to check.
TTFN

Jon.

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Re: Engine re-build... strange noises!

Postby mdt-son » Thu Mar 26, 2020 6:42 pm

Hi. I'd be interested to learn [*]what your findings were.

-Knut

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