Random E34 info that may be applicable to E9's

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Healey3000

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Hi,

This may be completely unrelated to the E9 but I thought I'd share something I learned from my E34 and its M30 engine.

Have any of you experienced a long delay in the oil pressure light going off during cold starts? I had that suddenly happen on my 535i and had to do some sleuthing.

The oil filter canister has a check valve at the bottom to prevent the canister from draining once the engine is off. It turned out that the valve suddenly failed, which caused oil pressure to take much longer to build. Since the valve wasn't available, the entire housing had to be replaced; pretty expensive too.

Interestingly enough, the new canister (bought from the dealer) failed in the same way in a couple of months. Convincing them about the failure mode was challenging but the evidence was too compelling so they replaced it under the parts warranty.

I have no idea if the E9 has a similar design or whether the valve it has is prone to failure. Hope this proves helpful.

Regards.
 
Ummm, IIRC on the m30 used in coupes, isn't the oil pressure relief valve part of the pump, living down in the block?

I suppose one could scrutinize the realoem diagrams and maybe suss it out.
 
Funny

Mr. Healy. If you look at the photo I posted on the toothy wheel, you will see the offending oil filter can. Bad design as I saw it and I did not experiment with the part. I posted on this in the past. Thanks for bringing it up again however. I wonder how many engines are toast because of that cheesy check valve. Shame on the BMW engineers for this one.
 
pamp said:
Mr. Healy. If you look at the photo I posted on the toothy wheel, you will see the offending oil filter can. Bad design as I saw it and I did not experiment with the part. I posted on this in the past. Thanks for bringing it up again however. I wonder how many engines are toast because of that cheesy check valve. Shame on the BMW engineers for this one.
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That's precisely what reminded me about the check valve. I haven't looked for past posts but have you had trouble with the unit?

Regards.
 
Honolulu said:
Ummm, IIRC on the m30 used in coupes, isn't the oil pressure relief valve part of the pump, living down in the block?

I suppose one could scrutinize the realoem diagrams and maybe suss it out.
Click to expand...

Hi,

The pressure relief valve is in the oil pump but this valve is simply there to keep the filter full of oil. It acts as a check valve and doesn't regulate pressure in any way.

Regards.
 
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My coupe always takes 6-10 seconds to build up pressure from cold :roll:

Although I've always tried to let the engine crank without touching the throttle (hence not encouraging a quick start) to let the oil circulate, is there a fix?
 
dj_efk said:
My coupe always takes 6-10 seconds to build up pressure from cold :roll:

Although I've always tried to let the engine crank without touching the throttle (hence not encouraging a quick start) to let the oil circulate, is there a fix?
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Hi,

It's relatively easy to verify whether the canister is draining down overnight. Take the top off and look inside; if the check valve has failed, the filter and can will be fairly dry. A functional valve will keep enough oil in there that it will be apparent.

The only fix is to replace the canister as I don't believe the valve is serviceable (I don't know if these older engines used a different design). Will a canister from a more modern M30 fit this block? If so, there should be plenty in junkyards that you can test before you install.

Repeated dry starts will make for an unhappy engine. I think ten seconds is too long (I recall my M30 taking about two seconds on a cold start).

Regards.
 
Healey3000 said:
The only fix is to replace the canister as I don't believe the valve is serviceable (I don't know if these older engines used a different design). Will a canister from a more modern M30 fit this block? If so, there should be plenty in junkyards that you can test before you install.

Repeated dry starts will make for an unhappy engine. I think ten seconds is too long (I recall my M30 taking about two seconds on a cold start).

Regards.
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+1, even six seconds it is a ot of time, i remember reading about an immediate switch off the light required in a healthy engine,

my engine has been recently serviced including a new oil pump, the light disappears in a flicker of the eyebrows

i can not see the point of the previous discussion about the relief valve in the oil filter, the only valve that i know in that area sits inside the oil filter support and it seems clearly to be designed as a safety valve for a case of a blocked filter to act as a by-pass for the oil

need to say that i still have the old version filter system (bottom removal bolt)
 
Been a while...

I accumate a bit of scrap in this shop and try to recyle before it gets out of control. The upright can went away. If memory serves me correctly, the spring beneath the check valve was weak. So the idea that this to keep the can full makes sense vs a plugged filter by-pass.
Not sure though. That being the case, then why a slow pressure build up as Mr. Healy described? I was told that BMW upgraded the piece with a steel vs nylon seat and other improvements. Yet, Mr. Healy had trouble with the factory replacement as well.
Library-5904.jpg

Gasket is different for sure, top or bottom bolt vs the upright can....The picture is of a 35 block w/ the gasket on use on my engine.(3.0 / 3.3) The offending can ....
Library-5226.jpg

What is for sure is that one needs to plug the 35 block to use the older top or bottom bolt can. This makes me wonder. If it were me and I was running the 3.5, I would do the block plug and run the old school can, convenience be damned. The upright can makes me nervous.
 
I have..

An extra set up that came off a 1980 633 CSI if that would fit and you need one. It includes the part that attaches to the engine and the canister with the valve in the bottom. I could send it to you for the cost of shipping. I don't think I'll ever use it and have lots of spares around.
 
I have a 3.5 m30 in my e30 and went thru 3 oil canisters to get one that worked. They'll all usually have a problem eventually. Not shocking that a new one from the dealer did. Better pictures of the problem here.

http://www.bmwe34.net/E34main/Trouble/OilCanister.htm

The style of the oil filter off the old m30 won't have this for obvious reasons. Not sure how interchangable the oil filter housings are. Mine is fine now, but I have a remote oil filter and oil cooler set up going on my car that will also eliminate the problem.
 
revitoff1o said:
I have a 3.5 m30 in my e30 and went thru 3 oil canisters to get one that worked. They'll all usually have a problem eventually. Not shocking that a new one from the dealer did. Better pictures of the problem here.

http://www.bmwe34.net/E34main/Trouble/OilCanister.htm

The style of the oil filter off the old m30 won't have this for obvious reasons. Not sure how interchangable the oil filter housings are. Mine is fine now, but I have a remote oil filter and oil cooler set up going on my car that will also eliminate the problem.
Click to expand...

Yeah, that's me - "Adnan". I had forgotten about that website!
 
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