That valve looks great. The little pin at the top is what falls out on occasion and can make a mess when it does. Yours looks OK..now back to finding out what is causeing the problem in #3 well.
Ok so I did a leak down test today, and indeed #3 is bad, the first time it was leaking from the intake and the second time from exhaust. Is this normal, and I don't understand how is it, the rest of the valves are good except for one?
What do you mean "the first time and second time"
During the leak down you'll bring that piston to TDC on its compression stroke then add air pressure. Also we're dealing with oil in cylinder AND loss of compression. How about a blown head gasket?
Adam
What do you mean "the first time and second time"
During the leak down you'll bring that piston to TDC on its compression stroke then add air pressure. Also we're dealing with oil in cylinder AND loss of compression. How about a blown head gasket?
Adam
Doesn't sound right to have two different readings. Sounds like maybe a valve was hanging open during the second test?
I know your very mechanically inclined and not trying to offend you.
Compresses air into the system is only one obvious sign of a blown HG between the CYL and a water jacket. It could still be blown elsewhere. Maybe start it and remove the oil cap. See if your getting excessive pressure into the crank case? I know it's not typical to have loss of compression and oil in the hole at the same time but if it was a typical problem I don't think you'd be on here for input from others.
Doesn't sound right to have two different readings. Sounds like maybe a valve was hanging open during the second test?
I know your very mechanically inclined and not trying to offend you.
Compresses air into the system is only one obvious sign of a blown HG between the CYL and a water jacket. It could still be blown elsewhere. Maybe start it and remove the oil cap. See if your getting excessive pressure into the crank case? I know it's not typical to have loss of compression and oil in the hole at the same time but if it was a typical problem I don't think you'd be on here for input from others.
Is ok, I am not offend. Two heads is better then one. I did that and no excessive pressure, I just replace ccv about a month ago, when she started smoking.
Hmm. Yeah the CCV crossed my mind but if that was guilty you should have oil in all the holes and it of course wouldn't have anything to do with compression. IDK maybe do another leak down test to be more conclusive. So if I remember you right you said it had a large amount of oil on this piston right?
Hmm. Yeah the CCV crossed my mind but if that was guilty you should have oil in all the holes and it of course wouldn't have anything to do with compression. IDK maybe do another leak down test to be more conclusive. So if I remember you right you said it had a large amount of oil on this piston right?
So the misfire and oil started at the same exact as the knocking and ticking? Stating the obvious but I don't see this being a simple fix. Maybe slap an eBay engine in it and move on. In my past experience its not cost effective to rebuild an engine.
So the misfire and oil started at the same exact as the knocking and ticking? Stating the obvious but I don't see this being a simple fix. Maybe slap an eBay engine in it and move on. In my past experience its not cost effective to rebuild an engine.
The head is out and ready for the machine shop. From what I can tell is all my exhaust valves are cover with carbon and looks burnt. But # 3 is the worst. Off to the shop tomorrow.
This is #3
Other valves
That don't make sense. There should be no oil in the combustion chamber, intake manifold, or exhaust manifold. How was that cylinder flooded with oil? Not closing certainly would cause your low compression but wouldn't cause oil or the knocking/ticking. Also what was keeping the valves from closing? Just some ideas. I'd hate to see you go through the trouble of rebuilding the head and still have a ring issue.
That don't make sense. There should be no oil in the combustion chamber, intake manifold, or exhaust manifold. How was that cylinder flooded with oil? Not closing certainly would cause your low compression but wouldn't cause oil or the knocking/ticking. Also what was keeping the valves from closing? Just some ideas. I'd hate to see you go through the trouble of rebuilding the head and still have a ring issue.
I get what you are saying, I will find out for sure when I take it to the machine shop later today. But from what I can see, maybe a leaking seal cause oil to leak down the valves cover with carbon, and dry up with the heat in the engine, causing the valve not to close. Sorry these were taken with my phone. But this is a close up.
A leaky valve seal due to a very loose stem is possible I guess. That still don't explain the noise. Idk. Hopefully the machine shop finds something conclusive when the take it apart. I'd make sure to mention the noise to them. Maybe they will be able to find something in the head that was causing the sound. If not I think I'd do the lower end. Adam
A leaky valve seal due to a very loose stem is possible I guess. That still don't explain the noise. Idk. Hopefully the machine shop finds something conclusive when the take it apart. I'd make sure to mention the noise to them. Maybe they will be able to find something in the head that was causing the sound. If not I think I'd do the lower end. Adam
Thanks Adam, what I came up with is, due to open valve the lifter was loose causing the ticking, it was only ticking on #3. Only time will tell, I will know for sure later.
Well, theoretically the lifter should have been tighter with the valve open but who knows. I'm sure we've both seen stranger things happen! Keep us posted.
Check for bent exhaust valve #3. If so, maybe oil caused build up on piston. The bent valve may be secondary. The oil may have come from cracked head. Post a pic of the underside of the head.
I just have one thing to add. Right after you place head back on the block and torque the last bolt,hook up the leak down tester to check for air sounds, anywhere. Of course each cylinder at TDC. Don't ask me how I know. It should save you a lot of heartache after you reassemble everything and find out you have a leak
Alan
Thanks but I said underside, which you also got. The head looks odd - some exhaust thread post holes missing & a M mark. Looks like a previous head job, badly done? Head looks like a bad refurb unit?
Ok so after a no call from the shop yesterday, I was very worry. So I decided to give them a call, and I am happy to say that my head is good and will be ready for pick up tomorrow. #3 valve and seal was bad, from carbon buildup. From what I have read online this seem to be a common problem with m54 engine. A word of advise to m54 owners, I would do a treatment at every oil change.
Thanks for the pics and update. My car at 132k is losing oil every 4-5k and am not sure where it's going.(CCV done) No nasty noises so far and oil changes every 7.5k miles. Good to hear the head is fine. Numbers 1 & 2 piston tops look really clean though. Maybe too clean? Hope it all ends well.
No problem, as for the clean piston, 5 and 6 were also clean. Could be due to the fact I spray Pb blaster on all piston a week ago. As for your car is it smoking on start up?
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