Author Topic: m42z famous timing chain (Read 3654 times)

E-30Dubbsz · « **on:** December 21, 2007, 06:09:34 PM »

well well well, I've been reading hundreds of informative articles, forums, warnings, etc. about the timing chain for the m42. Getting down to business. I need help. My chain can be heard loud n clearly in and outside of the car when its idling at 850rpm and gets worse driving around 3-4000rpms then cant really be heard afterwards. :eek:Surprisingly I'm scared even though I was expecting this problem soon I don't drive my car because it's not road ready yet. I'm not sure if the cold weather could possibly make it worse then it really is, but other then that the car sits in my garage and I run it once a week. I'm looking for the best list of parts that insure that department of the car for another 100,000km or so.

G-Man · « **Reply #1 on:** December 26, 2007, 11:23:21 AM »

I would change the chain tensioner first then see if the noise goes away. If it has, your problem is solved. Chain tensioner's need to be changed every 40K miles (or 70KM's). Chains are pretty bullitproof, chain tensioners are what go bad. M42 chain tensioners have been replaced by M44 chain tensioners. Do a search in the posts with tensioner as key word search. Lots of good info.

G-Man

sheepdog · « **Reply #2 on:** December 26, 2007, 12:27:05 PM »

If you are very concerned, pull the valve cover, it is easy to do and you do not need to replace the gasket on it. Take a look at the cam sprockets, get a picture if you can. The tops of the teeth should have rounded top, if they are spiked,m and sharp, then you need to replace the timing system.

On startup, if the car has sat a while an even somewhat worn chain can make noise. Especially with an old tensioner.

Febi Guibo · « **Reply #3 on:** December 26, 2007, 12:27:09 PM »

what's your mileage, and what kind of oil are you running...?

#1 - do the tensioner
#2 - make sure the oil filter housing is tight
#3 - get a new lower pan gasket, remove lower pan, check & *carefully* tighten upper pan bolts, install new gasket
#4 - consider replacing timing chain + rail (sorta the nuclear option)

E-30Dubbsz · « **Reply #4 on:** December 28, 2007, 03:18:41 PM »

Well, I did an oil change about 1 week ago then I found about the oil pan situation right after. Im currently running 10w-40 and my motor has 239447km on it. Mind you it's not driving on a regular basis, so if i was to redrain the oil is it possible to put it back in or is that a really dumb question. Only reason is so i can put in new gaskets and tighten the pan bolts.

n2motorsports · « **Reply #5 on:** December 28, 2007, 05:57:34 PM »

Quote from: E-30Dubbsz;40113

is it possible to put it back in QUOTE]

should be fine, unless you find metal shavings and such in the oil. i'd clean out a pan, let the oil drain into the pan and let it sit overnight, then slowly pour the oil back in the next day. by then, if there were any metal shaving, etc, it'll sink to the bottom.

sheepdog · « **Reply #6 on:** December 28, 2007, 07:56:36 PM »

Run it through a coffee filter if you can.

bosox1134 · « **Reply #7 on:** December 31, 2007, 07:22:37 AM »

how do you change the tensioner

n2motorsports · « **Reply #8 on:** January 02, 2008, 11:13:18 AM »

Quote from: bosox1134;40199

how do you change the tensioner

by searching

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

E-30Dubbsz · « **Reply #9 on:** March 19, 2008, 02:52:46 PM »

just did the tensioner. literally 10 minutes. Sounded like a diesel for a minute then it was fine. But, im still hearing my chain so im guessing that my rails are worn down.