Engine making tapping noise...

[abreut]

A common source of tapping noise around the head are exhaust leaks somewhere between the head and exhaust manifold, or exhaust manifold to down pipes to a lesser extent. I would check there as well, they sound exactly like noisy tappets.

[roccodingo]

Possibly the check valve in the oil filter / cooler bracket could be playing up as well. Wil try get you a pic of what to look for...

[dub be good to me]

Yesterday afternoon I swapped the oil back to 20W-50 (I only ran it with 10W for 10mins and heard no difference) and managed to get the sump off (found a 1/4 screwdriver/socket) and checked the oil screen... which was clean.

Re last three posts:

"I think it's a hardware problem not oil viscosity" (h100VW)
-What should I check next?
P.S Does anyone have an oil pressure gauge in the Eastern Suburbs I can borrow?

"A common source of tapping noise around the head are exhaust leaks somewhere between the head and exhaust manifold, or exhaust manifold to down pipes to a lesser extent. I would check there as well, they sound exactly like noisy tappets." (GrunMk1)
-I'm confident I do have an exhaust leak between head and manifold cause I can smell it, but not sure how this would cause a tapping noise?

"Possibly the check valve in the oil filter / cooler bracket could be playing up as well. Wil try get you a pic of what to look for..." (roccodingo)
-Removed the oil cooler bracket yesterday with no effect.

Thanks all, my Monday morning just got more interesting!

[abreut]

-I'm confident I do have an exhaust leak between head and manifold cause I can smell it, but not sure how this would cause a tapping noise?

On my cars it has caused an extremely tappety sound. Maybe its the sound of the valves snapping shut I'm not sure but the closer the leak is to to the head the more pronounced it is. Just recently I had one of the nuts holding on the exhaust manifold come loose, it actually came right off. Once i tightened it the tapping was gone.

[Jarred]

I've had an exhaust leak before. it sounds similar, but not the same as tappets imo. I have a reasonably good ear for different sounds though.

[roccodingo]

The image shows the three types of filter / cooler housings, part number 22 is the check valve for the upper oil galleries that run to the head, you need check that it isnt constricted with gunk or some other debris. All the ones i have seen are locked into the housing by having the thread peened over, wash the whole thing in a ggo carbon dissolving solvent then blow clean.

That is about the only point of restriction in the galleries to the head ( as far as i know) if the lifters are still rattley, its quite likely that the lifter bores are worn beyond specification allowing the lifters to rock in the bores to much, hence the rattle...



Would suggest the oil pressure check taken at the oil sender fitting at the end of the head before you get much further ...

[dub be good to me]

Dynamite, thanks mate.
I'll re-post this weekend when I've done the following:
-Check exhaust manifold for loose nuts and replace gasket if needed.
-Clean the check valve for upper oil galleys
-Checking oil pressure*
*Does anyone have an oil pressure gauge I can borrow?

[dub be good to me]

F#%k the weekend I sorted it last night

The winner is ..... Grunmk1!!

I got into it straight after work last night and discovered that in my haste to complete the kjet conversion in a weekend I made an elementary mistake

I had placed some of the exhaust gaskets on back to front (they aren't symmetrical) and mixed an odd gasket in with the set..
The back-to-front gaskets sealed but only just (blocking a considerable amount of exhaust), but the odd gasket was slightly thinner then the rest - hence the exhaust leak.

Replaced them with a full set of decent old gaskets I had lying around (getting an exhaust system next month so not to worried), bolted it down tight ... and it runs like a dream!

Thanks everyone for your posts, hugely appreciated

This weekend is now; Diesel fuel tank, hard fuel lines (if I can find any volvo ones!)

EDIT: Incidently, I replaced working tappets (i thought were the problem) with new ones. If anyone wants a good set of old tappets send me a PM

[abreut]

I'm glad you fixed the problem, I know how annoying that sound can be. Mine is sounding much better too after replacing the missing exhaust manifold nut!

[h100vw]

That happened to me on a 16V mk1 I built years ago. I had extractors on it and most of the studs wound out of the head when I took the std manifold off.

The gaskets swung out of place, as I fitted the manifold. It made a horrible noise!!!!

Gavin