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Topic: KR 16v Strange engine noise (Read 558 times) previous topic - next topic

KR 16v Strange engine noise

Hi

My 16v has developed a strange screeching noise. Immediate thoughts were the distributor as it sounds like a rotational noise coming from the gearbox side of the engine, topside. I have just fitted a newly reconditioned Bosch dizzy and the noise is still there (albeit it now idles a lot smoother so one improvement!)

Small backstory on the engine: Block and Head bought s/hand, both done a small number of hours running since recon prior to my purchase. Head is a Robert Cox polished & ported and block is standard 1.8. It has piper 270 cams with an adjustable vernier on the inlet cam. Done approx 2000 miles since install with zero issues until now.

A link to video showing the noise:

https://www.youtube.com/watch?v=nFw5DUmNpzs

It only starts doing it when the engine is hot and has no effect on how it performs/drives.

Any thoughts?

Thank you. :)

Re: KR 16v Strange engine noise

Reply #1 –
That's definitely coming from the gearbox end? It sounds just like an alternator with a failed bearing would do.
You could pop the auxiliary belts off and run it for a couple of seconds, see if that changes anything.
But obviously, don't leave it running, as the water pump won't be!

One other thing I could suggest is to use a long screwdriver like a stethoscope. Put it next to your ear and then on to various parts of the engine, to see if you can determine exactly where it is.
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Re: KR 16v Strange engine noise

Reply #2 –
Thanks for your reply.

Yes I have tried the old screwdriver trick. It seems pretty loud if you put it on the cam cover, dizzy end.

The alternator was a new unit fitted when the engine was built up. I may try running it without the belts momentarily just to rule it out. The noise is slightly 'behind' the engine revs. Do you think a vacuum/air leak could make the noise?
 

Re: KR 16v Strange engine noise

Reply #3 –
Sounds like a vacuum leak kind of noise to me.

Re: KR 16v Strange engine noise

Reply #4 –
If it only does it when it's hot could it be water related? or a bearing that running dry?
scs