Author Topic: Yet another Timing Chain Tensioner Post! (Read 7481 times)

e30s4evr · « **on:** August 08, 2007, 10:49:29 AM »

I just changed my timing chain tensioner last night, since there was no record of it ever being changed and the car has 155K miles -20K under my care. Being used to an S14 I always considered the M42 to be a pretty quiet motor. But now it's Lexus quiet at idle!!!

I released the piston before putting it in, which added about 2-3 minutes extra to the whole 15 minute procedure! There is absolutely no reason to not release the piston! When I started the car there was a brief rattle for 1-2 seconds and then everything was super quiet. The tensioner that was removed was also an M44 style tensioner and was of the same length and seemed to have the same spring stiffness as the new one. This weekend the lower oil pan comes off!

bmwman91 · « **Reply #1 on:** August 08, 2007, 11:07:53 AM »

Good man. Prevention is the best (& cheapest) medicine.

bmwpower · « **Reply #2 on:** August 08, 2007, 11:16:26 AM »

So the M44 tensioner, without a doubt, is the one you should get, right?

doucy2 · « **Reply #3 on:** August 08, 2007, 11:18:15 AM »

nice that you are keeping it up, PO let my m42 sit in a field for a 2 year, i had 4 bolt come off the lower oil pan, it was spilling oil everywhere, it is defiantly a weak point on the motor, good that you are going to check it out.

tjts1 · « **Reply #4 on:** August 08, 2007, 04:04:30 PM »

Quote from: bmwpower;31230

So the M44 tensioner, without a doubt, is the one you should get, right?

I think at this point only the M44 tensioner is available.

e30s4evr · « **Reply #5 on:** August 08, 2007, 04:20:39 PM »

True! Pelican parts comes up with the M44 tensioner when you put the E30 M42 part number in the search.

OT- I just drove someone else's 318is with a M40 flywheel in it (21 lbs) and it was so much faster than mine I'm wondering if something is wrong with my car! The flywheel can't account for so much. I expected more in 1st and 2nd, but 3rd was significant too. Even in 4th I think I noticed a difference. By the time I was in fifth there was no difference at all. Going back to my car, my tach seems to move like molasses! So I bought an M40 flywheel and clutch kit at lunch! I was told that I can easily shave 4 pounds off this -mostly near the outer edges so that would be significant. Can anyone confirm that?

Wise Old Dog · « **Reply #6 on:** August 08, 2007, 06:07:22 PM »

Mine ended up at 17.6 lbs. The machinist didn't want to go any farther. But he was used to working on American V-8 flywheels. 17 seems reasonable. Make sure you got the non A/C clutch. It will have springs on it.

KenC · « **Reply #7 on:** August 08, 2007, 08:47:24 PM »

Part Number for the chain tensioner?

tjts1 · « **Reply #8 on:** August 09, 2007, 01:28:22 AM »

http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search.cgi?command=show_part_page&please_wait=N&make=BMW&model=BE30§ion=ENGcam&page=3&bookmark=15&part_number=11-31-1-743-187-M40

http://www.m42club.com/forums/showthread.php?t=2925

Quote from: e30s4evr;31250

OT- I just drove someone else's 318is with a M40 flywheel in it (21 lbs) and it was so much faster than mine I'm wondering if something is wrong with my car! The flywheel can't account for so much. I expected more in 1st and 2nd, but 3rd was significant too. Even in 4th I think I noticed a difference. By the time I was in fifth there was no difference at all. Going back to my car, my tach seems to move like molasses! So I bought an M40 flywheel and clutch kit at lunch! I was told that I can easily shave 4 pounds off this -mostly near the outer edges so that would be significant. Can anyone confirm that?

Is the M40 flywheel work with the existing 42 starter, clutch and pressure plate? Is it a direct swap or do any other parts need to be changed?

Wise Old Dog · « **Reply #9 on:** August 09, 2007, 02:26:54 AM »

Need different clutch, pp. Starter is the same. Need shorter flywheel bolts.

Vladi · « **Reply #10 on:** August 09, 2007, 03:14:25 AM »

I changed my tensioner, too...but i didn't notice anything new. Engine still has the same sound.

gearheadE30 · « **Reply #11 on:** August 09, 2007, 09:55:12 AM »

I changed mine awhile back and it is a lot quieter, but I now have this metallic whine that varies directly with engine peed. I also put in a new chain, guides, and gears, so that may be part of it. I've never heard an M42 whine like mine, though.

As for the M40 flywheel, what is different about the cluch and pressure plate? An upside of the M20 flywheel is that it accepts a larger clutch. Is this true of the M40 as well? *hopeful*

Wise Old Dog · « **Reply #12 on:** August 09, 2007, 12:30:16 PM »

The M40 flywheel is a single mass FW. So the clutch is a spring hub disc to reduce noise, maybe other benefits as well. The FW has a deeply recessed friction face that the PP friction face is designed to fit into. No way around it, the standard PP will not fit. A larger clutch will not fit. One thing to factor into the weight calculations when deciding between the M40 vs M20 options, is that the clutch and PP for the M20 is heavier than the M40 setup, thus bringing the weight difference closer than it looks when just looking at the FW weights. If you aren't running a lot of HP, the M40 setup is plenty strong enough.

e30s4evr · « **Reply #13 on:** August 09, 2007, 12:59:32 PM »

Another thing is the diameter of the setup. The M40 setup keeps the weight close to the center... Hey every centimeter counts right!!

tjts1 · « **Reply #14 on:** August 09, 2007, 05:33:18 PM »

Quote from: Wise Old Dog;31272

Need different clutch, pp. Starter is the same. Need shorter flywheel bolts.

Excellent info thanks!