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Discussion Starter #1
hello

I had the engine from my touring rebuild about 8 month ago and its still using 1 liter of TWS 10W60 pr. 1000km?

I decided to have it rebuild as it had 310000km on it and used about 1 liter of oil pr. 8-900km i used a professional workshop to due the work to have some form of security if something was not right. the workshop have done S38 before and did 4 or 5 last year.

The engine was disassembled and measured and all was within spec. all rings, main and big end bearings was changed, cylinder walls was slightly honed and chain, tensioners oil and water pumps was changed. the head was cleaned, all exhaust valves changed and inlet valves and all seats was reconditioned. all valve seals changed and all new springs, fuel injectors, spark plugs and coils. and the engine was assembled with all new seals.

Engine was adjusted, valves and TB adjusted and balanced all running fine.

Engine was run in for about 1300km and oil was changed and it was run lightly for another 1500-2000 km ever since the engine have used 1 liter of oil every 1000km and had full oil change one time and has run about 12000km.

I have had it to the shop 3-4 times and they have "looked" at the oil issue, changed some gaskets but it had no major leaks. but all in all no result.

I have a friend that is a mechanic not BMW but still skilled. he suggested to pull the spark plugs and 1-4 was perfect light grey 5 was all black and nasty and 6 was also black. so he thinks it is burning all the oil on these 2 cylinders.

I think there must have been some fault in the reassembly of the engine at the workshop and wants them to fix it at there expense.

What do you fellows think?? all advice is very welcome!
 

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Discussion Starter #3
Actually we were planing to do a compressiontest when my mate and I pulled the plugs but after cylinder 2 the tester broke and as I left for my job at sea the next day we decided it would have to wait till I return in 3 weeks time.

The funny stuff is i asked the workshop that rebuild the engine to do a compressiontest the last 2 times it was there for them to fix the problem but they did not do one they seems to think it will not say anything about oil usage??

I payed loads of money to get this rebuild done and I was fine with that if it did not still burn all that oil.
 

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Will a compression test say for sure where the engine is using oil?? Are there other tests I could do or get a workshop to do??

Can you remove piston 5 and 6 from the engine while it still in the car??

Any help is appreciated Thanks
 

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Will a compression test say for sure where the engine is using oil?? Are there other tests I could do or get a workshop to do??

Can you remove piston 5 and 6 from the engine while it still in the car??

Any help is appreciated Thanks
a compression test tells the cylinder pressure. If there is poor sealing, either rings or valves, you'll have low compression. A problem with the rings could certainly cause oil consumption. I would not attempt to remove pistons with the engine in the car. Realistically, with the right equipment and experience, removing the engine is not a big deal. Valve guide seals could also be a source of the oil into the combustion chambers.

(Compression test tell cyl pressure, a leakdown test can narrow down sources of leakage to rings vs valves)
 

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I'd certainly start with a compression test.

strikes me as very odd that the re-build company didn't want to do a compression test, and, that they arn't on the case of finding out why it's using so much oil.

My car (148,000 KM) uses 200ml (maximum) per 1000km.
 

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Discussion Starter #8
Will get some tests done and have another talk with the workshop when i come back home in 3 weeks time.

Thanks for the great advice. Keep em coming :D
 

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Strange story indeed. Especially the "professional workshop". Did you pay them already? Hope not. How can you pay for a partially rebuild engine (especially the failing parts causing oil usage) and the end result is basically the same. I would sew them if possible.
Is the engine running fine besides the oil usage. Reving, torgue, idle etc....?

Willem
 
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