I’m looking for technical help or recommendations on: __Engine smoking after replacement fitted.
Hi all, please can I pick your brains on the following.
My partner has a 2010 NC, 1.8. The engine started smoking bluey-grey smelly smoke, large oil consumption and fowling plugs. I changed the PCV valve, but it made no difference and so, after advice from three mechanics, they agreed that the oil control rings had probably gone and that it was toast. It had 180 k miles on it.
I sourced an 85 k engine, which I witnessed running – with no smoke, good compression and sounding good.
I fitted it and I have exactly the same smoke characteristics as I had before. This is also with a new PCV valve. The oil consumption is high too – with darkened plugs.
I can’t believe both engines are toast in exactly the same way… So I now suspect the cats. The manifold one shows a slightly higher temp then the tail end of it, though it is difficult to measure with the shroud on.
The downstream cat’s temp’. seems to measure the same – so am I right in thinking that this cat looks to be US? I would have thought the manifold one would have been damaged first by the previous engine… Could collapsed Cats cause backpressure in the engine – causing the oil past the rings - causing the same smoking as with the previous engine?
The cats are expensive and I am wary of spending out on them if this engine is toast too.
It’s very frustrating as apart from the smoke the engine runs beautifully and manages 20 mph in 5th no problem - and on up the range.
Has the whole inlet from the prv and also the exhaust system been liberally coated in oil from the old engine and needs to have these items either cleaned out, especially the inlet side and then 'italian tuned ’ to get rid of the rest ?
Hi I used the inlet of the new engine, so it shouldn’t have been contaminated, the exhaust manifold etc though is from the old engine - so yes that could still be caked in oil. So far I have done about 50 miles.
My friends 1.8 was using oil, changed the engine to a “known” 60K engine and that also used oil.
I rebuilt his original engine, the issue was the oil control rings, there aren’t enough oil drains in the piston. He has now done 700 miles with no oil usage.
The only way to fix these engines is to rebuild them, your 80k mile engine will have the same issue.
My rebuild video is here:
I now have the second engine to rebuild at some point.
Hi, you may well be right and at some point soon I may well have to rebulid it. The thing I can’t get my head around is that I physicallt witnessed this engine running in the car it came out of - and there was no smoke. The smoke I am getting is exactly the same grey suliphuric smeeling stuff I had with engine number one, so my thinking is that it must be something common with the first engine (other than its desighn floor) Thanks for your link to the rebuild video. I nay well have to follow it closely and, as you say, rebulid this one. Cheers
One of my mates used sea foam ( bit like cataclean ) in his motorbike but got the dosing wrong ( too much )
His bike smoked until he got rid of the fuel that was in it and it got fresh untreated fuel through it.
You said this:
“I fitted it and I have exactly the same smoke characteristics as I had before. This is also with a new PCV valve. The oil consumption is high too – with darkened plugs.”
If the new engine is using oil, then its the rings, you wont be using oil if its residue left over in the exhaust for example.
You’ve removed one buggered engine and fitted it with another, well done. There is a good reason for this and it’s why the car the second car was scrapped - the engine was buggered.
If you want a link to an explanation let me know, otherwise it’s:
Engine rebuild time.
When engines are destined by default to destroy themselves they will, buying another untouched one won’t circumnavigate this feature.
Yes please send me the link . The car the engine was crashed and I observed the engine running and it appears to be the same engine.
There was about a three week gap between then and receiving the engine so maybe it gummed up when drained and transported. Either way I am preparing myself to rebuild it.