Distorted sump

[doffo25]

Hi Guys

I was replacing my sump back into position having changed the rings and big end shells. I had difficulty in raising the sump into position whilst keeping the gasket in position. I therefore decided to remove the oil cooler to make the job easier...which it did. The sump went in well and I tightened the sump bolts with no problems and little effort.

However when I raised the oil cooler into position I noticed it wouldn't sit flat but would rock around a high spot which is ringed in the pic. I reckon the high spot is some 3mm high.The perimeter of where the oil cooler sits is flat The oil cooler is flat.

I am at a total loss to understand what is going on.

Anyone have any bright ideas?

regards

David

[John37]

Well since no one else has replied here's my 2P worth.
You say the problem area is 3mm high. Is that measured at the edge of the sump? If so, 3mm there = 1.5mm in the middle. That's still not acceptable of course.
Is the oil cooler the original one? Have you put a straight edge across the sump? I'm wondering whether the high spot is the sump or oil cooler?
Castings have been known to creep with time and heat. I'm replacing my exhaust manifolds due to that. 2 done so far. They were about 2mm out of true. Despite being big lumps of cast iron, they had warped badly.
You say the sump bolted up easily. That may seem the case but is there any possibility there's something above it that's pushing that particular area down? Drop the sump again and check it's flat.
If you find the sump or oil cooler face is distorted, it looks to be a simple job to machine it flat.

[doffo25]

Thanks for your reply John.

I removed the sump and there is nothing trapped causing the distortion. The distortion is on the sump.

I did try to tighten the oil cooler bolts to see if the gap disappears when tightened and it did so quite easily.

I suspect the distortion was present before I disassembled it and it didn't leak before......

I believe the oil cooler sump is not pressurised (?) and so im hoping that a smear of Hylomar should do the job