SICAMG

Engine and trans back in and running after a long battle with the custom exhaust system....on my back in the garage,.... and only to have the same ...but better , oil pump whine from engine ! Had a feeling it would be there but hoped for the best. The engine was gone through with a fine tooth comb and every possible avenue was explored for this noise and nothing was found. Even the feared hardened O ring was not that bad so couldn't even point to that.
Anyone know where oil pressure should be hot at idle?

E55Greasemonkey

These cars had an oil pump whine when they were brand new. Was yours exceptionally loud?

SICAMG

Not really but when cold ….yes. The Bizol oil made a very big difference but always still there. I have heard other cars and they where very loud compared to mine ……..but then again some where much more quiet.
I put in a new pump,chain ,tensioner, bearings on the lower end and although better, still hear it. Mind you that was not just the reason for going into the engine. Head studs arp rod bolts timing chain and some porting and header/exhaust build..{really sucked} where done along with building the trans so if the engine was quieter that would have been great.

StarvingArtist

Your car is well cared for. Someday I'll do a round of maintenance like that on mine How much were the bottom end bearings?

SICAMG

$400.00 for rods and 180.00 for mains. Kinda pricey for just bearings and is why I didn't get them coated. Everything else was fairly priced.
Engine also only has 70,000 miles but I figured do it all now so I can go race and crank up the boost for years to come.
Awesome engine to work on !!!

E55Greasemonkey

How'd the rod bearings look? I was told of an E55 throwing a rod by another dealership tech. Don't know the circumstances of it though.

SICAMG

Pretty good considering the beating that's been put on it !!!!

SICAMG

Also found these engines have an interesting oil pressure swing from 25-30 psi at idle to 90 psi hot.

BC928

SICAMG

Ebay has them for the same price as my dealer did. Original factory too from the Ebay dealer aswell.

rilonprime

Check out this video, I just found on another thread re: engine/tranny whine:


If we can figure out what's going on here, maybe we can solve our whine issues?

SICAMG

Pump cavitation.

rilonprime

That's what I think too. How do we solve it? Is there a way to bleed the tranny?

SICAMG

No such thing as bleeding the transmission.

I did my part with this issue so we will let someone else take a stab at it LOL

stroock6394

it's the oil pump that makes noise not the transmission

because of the way the M113K is so enormous, it wouldn't fit into the W211 engine bay without modifying the oil pan to fit around the subframe, so there's two separate oil pickups and it's noisier

the S and CL don't need to do this so they don't make as much noise (5:53 in this vid)


i've also noticed the pump is noisier if there's a little bit too much oil in the pan, such as right after changing the oil i'd pour in the full 9 quarts, and i guess since not all the oil had drained the level was still a bit high and the pump was noisier... but after driving enough and oil gradually burns off it quiets down

stroock6394

easiest (while being the least messy and risky) thing to do is take a little fluid transfer pump (such as: https://www.fcpeuro.com/products/flu...RoCiLEQAvD_BwE) and suck out some transmission fluid through the filler tube toward the back of the engine

but this won't change the oil pump making noise

SICAMG

It is believed through our testing that the front scavenge is sucking the front pan dry , giving the cavitating type sound. This was "sort of" verified by removing the front drain plug when the engine was running and very little oil came out meaning there was not enough drain back to the front scavenge to feed the demand from the suction side of the pump. Not a big deal since this is not where the oil supply to the engine comes from, but just a secondary feed to the pressure side.
I could be totally wrong on this as I am not an engineer.

StarvingArtist

I usually get a couple quarts out of the front when I drain it, but I can't remember if the whine starts immediately or waits a few seconds. I think it's immediate, which would mean it has oil to pump. I'm not an engineer either, but don't sell yourself short. Being sensible and reasonably intelligent goes a long way in this world

SICAMG

Starving ..I never get more than 3/4 to 1 quart from the front.....strange.
We also dissected the pumps to learn exactly how they work. Over engineered as usual LOL but interesting none the less..
I also forgot to mention that I strongly believe that bearing clearance plays a role as well. The more miles, the wider the clearances get with more oil being "used" by the engine and not being "backed up " by way of pressure. So the pump is acting a little different ???? That is why I think oil thickness and cold start play a very large role in the noise due to pressure ??

stroock6394

hey you don't need to be an engineer to have correct info lol... but this sounds about right

StarvingArtist

I don't think I've ever measured how much oil comes out, but it's at least a quart plus.