E30 M42 engine noise

[E30/318is]

As i stated in my introduction thread i recently acquired a "project".
This is my 1st BMW so needless to say i'm working my way through this via lots of m42club advice/thread info, & a little mech-background on my part.

I managed to get it running today although hesitantly as it sounds terrible & idles poorly. I liken the sound to ball bearings rattling around or a noisey diesel engine. It doesn't appear to be coming from the front or timing chain area, but from the intake side. Its loudest around the intake manifold but i don't know if thats a valvetrain issue funneling up through the intake assembly or not. I did a compression test & the #'s were from the front/rad to rear/firewall: 230#,230#,230#, & 235#'s. I pulled the valve cover to snoop around & judging by the cam area the chain does not seem loose, nor do i see any signs of damage to the cam lobes. Of course this is limited viewing, but thats all i could see. When running it (noise) doesn't dissipate or increase, but stays the same level & increases/descreases with acceleration/de-celeration. I let it idle for approximately 5-7 minutes & the coolant temp. leveled off in a normal zone. I did spray some TBI cleaner around the intake mounting area & it did increase rev's when i hit the middle of the manifold area. The plug's appear normal, no damage or carbon issues & the wires are a fairly new looking Bosch set.

Any thoughts or suggestions on my next step?
Also is the Bentley E36 manual the best source for working on an E30 M42?
I'd like to have a refernce source on hand, esp. if i have to start doing any teardown.

Thanks in advance for your help.

[DesktopDave]

Sounds like a good project...seems like the engine is tight, I can't think of anything that'd make a sound like that.  Maybe a rod bearing?

Vacuum leaks are a problem with these engines.  You might want to check out the TB heater threads, if you haven't already.

The e36 manual is great for the M42 engine.  The rest of the car is an e30, not too complicated.  It's nice to welcome a fellow Pennsylvanian to the club!

[E30/318is]

Thanks again Dave.
God i hope its not a rod bearing. *ugh*
Pardon my ignorance, but "TB heater" threads?
I'll order up an E36 manual.
Seems like alot of PA'ers dig the E30's.

[DesktopDave]

Yeah...the throttle body heater removal mod.  It's a big rat's nest of vac lines under the intake.  You have to see it to believe it.  Check it out on RealOEM.com:

http://www.realoem.com/bmw/showparts.do?model=AJ93&mospid=47318&btnr=13_0578&hg=13&fg=15

The e36 manual is on the site somewhere in the reference section.  I posted a URL for a download too...nice to have a backup copy.

Seems a lot of PA'ers have rusted hulks for BMW's too.

[romeomike]

A common thing for your M42 to-do list is replacing the timing chain tensioner:

http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=11-31-1-743-187-M40&catalog_description=Chain%20Tensioner%20Piston%20for%20Timing%20Chain%2C%20E30%20318i%20M42%2C%20318iC

I have Pennsylvania roots as well, having lived the first 21 years there (Schuylkill County).

[E30/318is]

Well i think i'm going to try the tensioner & cross my fingers.
After reading a few other threads on here of some others symptoms, one in particular resonated with my scenario. He changed it out & all is well. I work for a parts jobber & can get an o.e. tensioner for $29 + shipping so what the heck, its worth a shot.

Theres alot i'd like to do with this car, but before i even start i want to get it running obviously before making any further investments. If its integral & terminal, i may just part it or consider a swap.

[DesktopDave]

Keep us up to date, sounds like you're headed in the right direction.

[E30/318is]

Shall do.
This sit & wait part sucks.

[E30/318is]

Finally got a chance to install the tensioner between the storms.
Unfortunately its still the same.
The old one i took out was shorter in length & had an o.e. BMW stamping & part # on it
& was difficult to compress. Being an older type of tensioner (i don't know when they replaced the older version with the newer) i've got to wonder if/when it was ever replaced. The car does have 179K on it, but has excellent compression #'s as stated above. Also the engine & inspection lights are coming on now. The engine light goes off if rpm's are increased, but comes right back on when it levels out which is a very rough & stumbling idle.
Don't know which direct i should head next, maybe drop the lower pan this weekend & look for surprises i guess.
Any suggestions would be appreciated.

[Frank Gallegos]

There was a near by 318is for sale in my area that I went to check out.  When I started the m42 up it had a noise that sounded a lot like you have described in your post.  After further questioning of the seller, it turned out that he and his father had done a head job on the engine and revealed to me that not until after the work did they find out that there was not enough oil that was being pumped up into the upper part of the engine.  When the engine ran long enough and the revs were pushed up a bit the noise would fade away signifying that there now was adequate oil being circulated.  The seller than wanted to get rid of the car as he needed cash and did not want to put any more work into the 318.  

At this point I would point you in the direction of making sure your engine is working its oil properly through your engine.

Best of Luck,
Frank

[E30/318is]

Great weather today on our nations birthday & what better way to celebrate than dropping your oil pan & finding this:

Blocked p/u tube.

All this was inside the tube (excluding the bolt).

Same "stuff", just flipped over.

Nice teeth marks, *chomp*chomp* :rolleyes:

I reckon these are all timing component debris, but the item next to the bolt is a piece of a rubber,molded gasket of some sort. Can anyone shed some light on this if its not all timing pieces? The bolt was laying in the pan. This was not everything b.t.w. After taking these pic's i crawled back under & cleaned out at least 30 small pieces that were still inside the tube housing. My worries are that some of this crap got past the screen & well, you know.

I'm going to gather up everything i need to replace such as chain,gears,adjusters,& water pump. Anything i didn't add that y'all recommend would be appreciated. Of course i plan on changing belts,hoses, & taking car eof that vaccuum mess while its down too.

One last thing, i don't have a Bentley yet (thought a seller in the For Sale area woulda replied by now) so i'm going to order one online today. In the meantime whats the best link for info to start on this project?

Thanks in advance guys. I really hope to bring this car back to life.

[RED IS 91]

Here's a start

http://www.esatclear.ie/~bpurcell/318ismaintenance.html#timingchain

There is also an online manual

http://m42club.com/forums/showthread.php?t=2282

good luck

[E30/318is]

Thanks RED IS, i'll definately use them as a resource when i'm able to get around to it.
I was hospitalized tuesday morning for a few days & needless to say the medical bills take precedence over my M42 grocery list.
Can't wait to get it running though.