Sad to hear this Steve, but is it really possible to have an M6 nut passing through the valve oppening ? Hard to believe...
Hope that you solve it without any damages.
Good luck!
Hope that you solve it without any damages.
Good luck!
Solved - bad engine noise!!
- Thread starter Stevehose
- Start date
I wouldn't think so either but if @stphers has seen it, I believe it.
FYI- the times I have seen this the object is NOT loose in the bore, it is imbedded in the combustion chamber or in the piston. The sound you hear is not a popcorn machine noise - it’s the sound you get from a piston hitting the head through a piece of metal. The last one was a washer standing straight up embedded in the piston.
Ugh... No Bueno...
Yes I have been having nightmares about your mentioning this, I don't see any evidence of this on the piston tops but it is top of mind. I'm going to start it back up without the valve cover on after my fiberglass oil shield is ready.
Got my fingers crossed for you Steve.
This whole thread has the hair on the back of my neck standing on end. Sun just came out here thing I’ll drive my car with the radio off for a while.
This whole thread has the hair on the back of my neck standing on end. Sun just came out here thing I’ll drive my car with the radio off for a while.
Here is the maximum you can press the valve, and this is under the maximum requirement of the Iron Maiden.
judge yourself
judge yourself
@deQuincey - I agree it's a close fit but Rick has seen it happen so I must consider all expert opinions until I sort this out
I appreciate the pics
Just in from Blind Squirrel Productions Inc. - the M30 oil spray shield:
stphers
Well-Known Member
Think about it, there are only 3 places for anything to get inside the chamber, intake, ex or spark plug hole. Hard to think anything will come in thru the ex and unless the plugs were out or something has broken off the plug, the only reasonable idea that something could get in is thru the intake. I did have a 2002 eng will a high lift cam have a nut go right thru it, noise was there for a few seconds and then gone, we did pull the head anyways and you could see the damage but no sign of any nut anywhere.
Are we really sure that the noise is coming from inside the hole or is it from the rod emulating the noise upwards? Just a thought Had a mini many years ago come into the dealership with a metallic noise from the eng, pulled the head and found a circlip was missing? lost ? It was British leyland The wristpin had walked its way right into the cylinder bore Quite a mess new bottom end was put in under warranty, wouldn't do a coplete?
Thanks, Rick
Are we really sure that the noise is coming from inside the hole or is it from the rod emulating the noise upwards? Just a thought Had a mini many years ago come into the dealership with a metallic noise from the eng, pulled the head and found a circlip was missing? lost ? It was British leyland The wristpin had walked its way right into the cylinder bore Quite a mess new bottom end was put in under warranty, wouldn't do a coplete?
Thanks, Rick
This will be my focus tomorrow, I am not sure it is coming from the cylinder or somewhere else close by. The missing M6 nut(s) by the carb intakes is either the cause or a coincidence at this point.
kladd
Member
More than 10 years ago I dropped 2275986 off at Jack Deren's shop. The purpose was to prep the car for participation in the 50 Years of Champions celebration at Daytona.
A few days later Jack called. "Did you know you have a mouse nest inside your motor?" Yep, mice had crept up the exhaust and thru the exhaust valves of I forget which cylinder. We know it wasn't from the intake side because the car was/is always stored with a string of tennis balls stuffed in the intake trumpets. Compressed air combined with a shop vac was used to remove all debris. The mice themselves apparently abandoned ship in time.
Fortunately there were no permanent affects and the car performed great. Its now always stored with big foam balls stuffed in the exhaust as well!
Hope all goes well. Stuff happens with cars.
A few days later Jack called. "Did you know you have a mouse nest inside your motor?" Yep, mice had crept up the exhaust and thru the exhaust valves of I forget which cylinder. We know it wasn't from the intake side because the car was/is always stored with a string of tennis balls stuffed in the intake trumpets. Compressed air combined with a shop vac was used to remove all debris. The mice themselves apparently abandoned ship in time.
Fortunately there were no permanent affects and the car performed great. Its now always stored with big foam balls stuffed in the exhaust as well!
Hope all goes well. Stuff happens with cars.
kladd
Member
Oh, and an unscrupulous mechanic would have had an absolute field day with my checkbook.
Thank you Jack!
Thank you Jack!
The news from the front is not super encouraging - my 2002 Tii owning brother in law and our friend who is a long time BMW mechanic came over to have a listen and we've come to the conclusion that the very disconcerting clanking noise sounds low in the block so we shut it down. I didn't get a video in time. It would not make the noise at idle but slightly off idle it kicks in and isn't pretty. We did it with the clutch in and out which made no difference. So the next step is to drop the oil pan gasket (I hate this job) and see if there is a horror show in the bottom half. My garage is not much bigger than the car so not a lot of room to do this.
We agree that the engine is likely coming out, so hopefully in a year or so I'll be back on the road as I don't have a lot of time on my hands yet I want to do this myself because I've always wanted to rebuild an engine. I'll continue this thread all the way to completion be it a total rebuild or otherwise. The cylinder head that I got from Don is in great shape so I won't have to mess with that. If I do a rebuild it's getting 10:1 pistons and anything else you all suggest (already has a Schrick cam). That's all for now, thanks for the suggestions!
We agree that the engine is likely coming out, so hopefully in a year or so I'll be back on the road as I don't have a lot of time on my hands yet I want to do this myself because I've always wanted to rebuild an engine. I'll continue this thread all the way to completion be it a total rebuild or otherwise. The cylinder head that I got from Don is in great shape so I won't have to mess with that. If I do a rebuild it's getting 10:1 pistons and anything else you all suggest (already has a Schrick cam). That's all for now, thanks for the suggestions!
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Thanks, better here than on the way to Sharkfest!
rod knock?
I did a spark plug pull on each cylinder which made no change (a simple test for rod knock) but we'll see when the pan comes off.
Well, that sucks. Steve, I recently discovered a similar noise on an '02 which turned out to be a worn main crank thrust bearing. I posted on the 2002 FAQ a few months ago with pictures. You can easily get a preview (before disassembling anything) of that by eyeballing the crank axial play. Mine was like 1/8-3/16" when it should be nearly imperceptible by eye.