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big end bearing fault, found strange broken ring/sleeve (solved)

Posted: Tue Dec 27, 2022 1:06 pm
by Frank +8
Hello friends,

happend again ...

short story:
Oil pump relive valve stuck,
big end bearing fault, crankshaft ok,

please have a look at the pictures,
I found a strange broken ring/sleeve,
the metal surface shines like galvanized brass color,
the outer diameter could be 8mm, I am not sure if these 3 pieces are the only ones?
see Attachement

does anyone have an idea where the sleeve came from?

Image

long story:
bought the car in very good condition, 3.5 SD1 Engine, SU´s,
engine overhauled by professionell (?) engine builder,
the main block looks like Alu flame sprayed,
after ~ 5.000 km, big end bearing fault,
the relive valve stuck, oil pressure was lost, although I switched of immediately,
the big ends bearing are killed,
crankshaft was ok, like new, I found abrasive sand in the sump,
I am sure the engine builder does sandblast the block, and waste of sand remaining inside the block/blind holes...

I polished the relive valve and the bore, it run pretty smooth then,
full oil pressure!
engine run perfekt for 10.000 km,

last autumn, it happend again, the valve stuck again,

now I bought the "tad pole" relive valve, it should help for the future,
I will clean up and rinse the block gain, every oil bore!

Thanks for your ideas!

Your Frank

Re: big end bearing fault, found strange broken ring/sleeve

Posted: Tue Dec 27, 2022 5:08 pm
by stevieturbo
It's a little like a valve collet, but it isn't

anything from the dizzy ? pump drive at the dizzy ?

can't think of too many small round parts

Re: big end bearing fault, found strange broken ring/sleeve

Posted: Tue Dec 27, 2022 5:52 pm
by ChrisJC
My first thought was a collett, but they are split into two, so as Stevie says, not a collett.

I can't think of anything else they could be!

Maybe ask the engine builder?

Chris.

Re: big end bearing fault, found strange broken ring/sleeve

Posted: Tue Dec 27, 2022 8:41 pm
by GDCobra
I also thought valve collet, possibly from more than one valve.
Any idea on material? Is it magnetic?
Based on the fact you've found "sand" in the engine previously it could also be something which doesn't belong in there which the un-professional engine builder allowed to migrate from elsewhere?

Any chance of a closer picture with the parts cleaned up?

Re: big end bearing fault, found strange broken ring/sleeve

Posted: Wed Dec 28, 2022 1:52 pm
by stevieturbo
Even looking through parts, not too many round cylinders

https://www.lrworkshop.com/diagrams/lan ... e/109in-v8

Core plug in end of rocker rails ? ( or other core plug ) but it doesn't look like a core plug.

part of dipstick tube ? seems unlikely.

locating dowel for something ? that clearly isn't where it should be ? can't think of any so small.

Re: big end bearing fault, found strange broken ring/sleeve

Posted: Wed Dec 28, 2022 4:39 pm
by Blown v8
The metal sleeve on some rocker cover gaskets ?

Re: big end bearing fault, found strange broken ring/sleeve

Posted: Wed Dec 28, 2022 6:44 pm
by Frank +8
Hello Blown v8,

you are right!

it is the sleeve out of the rubber sealing of the valve cover!!!

many thanks!

hopefully my cam ist ok, I will check for,

Your Frank