I have done a lot of engine work on my Series III 4.2 recently. Now she is running well again, but I noticed a bit of valve chatter at some revs. It was not pinking, nor was it the dreaded loose valve guide problem, but just a bit noisier than I would like under some conditions.

I took off the cam covers to check that the valve gear was receiving sufficient oil. There was a good pool of oil in each recess. One at a time, I removed the cam bearing caps and confirmed that each bearing was in good condidtion and had a good film of oil. So no problems found there.

For a while, I have been running the car with the engine oil level about halfway from the low to the high marks on the dipstick. So I decided to top it off right up to the high level mark.

Now, the valve chatter is noticably reduced!

Has anyone else noticed the valves being noisier if the engine oil level is not right up to the full mark? Seems odd to me, but there it is!

 

Not what I would expect.

Your top-off would have been, what? A pint? A quart?

Given that the engine has an 8-9 quart sump I can't imagine how topping-off would change oil flow/pressure/distribution in any way.

But I'm just three sips into my first cuppa coffee

Cheers
DD

 

I'd double-check the timing chain tension. A slightly loose chain can make a similar noise, especially from a cold start.

 

It took about a litre and a half of engine oil. More than I was expecting actually. So from low to high mark on the dipstick must represent close to 3L

I’m reasonably confident the valve chain is at the right tension. Would noise be due to loose chain or over-tight? My chains are new, having been replaced during engine stripdown earlier this year

 

The primary (lower) chain has a hydraulic chain tensioner which is driven by oil pressure. So it would not be too loose or too tight
I doubt if the low oil quantity could contribute to low pressure in this tensioner

For non-metric persons 1 litre is as close as dammit to 1 US quart. (1 litre = 1.056 quarts)

 

I should have specified the secondary chain - which can be adjusted.

 

When the uppper chain was replaced, did you use a new after market tension set.

I've read of poor quality resulting in early failure.

Just a stab...

Carl

 

Yes the chain guides were replaced. I re-used the original hydraulic tensioner as it was in good condition and new ones were not available anyway. Gauze filter was cleaned out.

The upper chain is not slack. Could it be too tight? It looks and feels right to me, with a bit of “give” in it.

 

Andy, why not drive it for a bit and see if it settles down?