Bimmerfest - BMW Forums

Bimmerfest - BMW Forums (http://www.bimmerfest.com/forums/index.php)
-   E34 (1989 - 1995) (http://www.bimmerfest.com/forums/forumdisplay.php?f=102)
-   -   reasons to change your timing belt on a m20 (http://www.bimmerfest.com/forums/showthread.php?t=546561)

south26 06-05-2011 07:04 PM

reasons to change your timing belt on a m20
 
Hi, I was taking a head off a m20 from a e34. I bought the car to part out. I was told that it had a blown head gasket. Well I have never seen a gasket go like this. I did not count but a number of rockers broke. 6 valves broke, one stuck in a piston. 4 out of the 6 pistons had holes in them.

http://i678.photobucket.com/albums/v...4/P6050127.jpg

http://i678.photobucket.com/albums/v...4/P6050124.jpg

http://i678.photobucket.com/albums/v...4/P6050123.jpg

http://i678.photobucket.com/albums/v...4/P6050126.jpg

http://http://i678.photobucket.com/a...4/P6050125.jpg










Remember change your timing belt.


Andy
_________________

luckydog 06-05-2011 07:52 PM

1 Attachment(s)
Yes i think thats good advise.That a lot of damage for one event. I can only imagine the sound that made. good pics too. I have two m50 h/g blown engines on Dolly's for the day i decide to rebuild one.

ross1 06-06-2011 03:31 PM

Wow, that's comprehensive. Bad head gasket, yyea. Perhaps mail a valve head to the seller

gomfrddy 06-06-2011 04:55 PM

Quote:

Originally Posted by luckydog (Post 6112775)
Yes i think thats good advise.That a lot of damage for one event. I can only imagine the sound that made. good pics too. I have two m50 h/g blown engines on Dolly's for the day i decide to rebuild one.

it sounds like a miniature machine gun or sewing machine....ratatatatatatatatata

Radian 06-06-2011 07:49 PM

...But it's got a Mobile 1 oil filter! :rofl: :rolleyes:

south26 10-16-2011 08:56 AM

Reason to change your timing belt.


Andy

robertobaggio20 10-16-2011 12:30 PM

Quote:

Originally Posted by ross1 (Post 6114436)
Wow, that's comprehensive. Bad head gasket, yyea. Perhaps mail a valve head to the seller

Hi Ross ole' buddy ole' pal !! How are you ??? Have a lovely day !!

south26 01-22-2013 03:22 PM

Hi, I thought I would bring this back for those with a m20.


Andy

BMR_LVR 01-22-2013 04:22 PM

Ahhhh .... the joys of an interference engine with a timing belt (that is not properly maintained/changed out) :cry:

_Ethrty-Andy_ 01-22-2013 08:33 PM

reminds me i have to do the one on my M40 in my 3er sometime in the next 6 months. ergh. its not a difficult task on either, ive done it several times, but just so time consuming!

south26 01-23-2013 06:32 PM

but not doing it is some much more time consuming.


Andy

_Ethrty-Andy_ 01-23-2013 11:43 PM

not a true-er word was said

south26 10-09-2013 06:22 PM

Just a friendly reminder to those of us with a m20.:)


Andy

MustangAndy 10-10-2013 05:30 AM

Quote:

Originally Posted by south26 (Post 7887743)
Just a friendly reminder to those of us with a m20.:)


Andy

Does this apply to the M30s as well?


_

imae34driver 10-10-2013 07:26 AM

Thats what costed me my first car and second car.. Cruising along then all the sudden SNAP!

Time for a new car.. Hadnt gottn into swapping yet.. Seemed to hard back then lol

south26 10-10-2013 04:10 PM

Quote:

Originally Posted by MustangAndy (Post 7888474)
Does this apply to the M30s as well?


_



Nope the m30 has a chain. Only the 89-90 525i has the m20.


Andy

south26 01-04-2015 07:23 PM

Bump to help with reasons to change your timing belt.


Andy

south26 07-10-2016 07:07 PM

For those new people that have not seen what happens when you forget to change your timing belt.


Andy

aliff01 07-17-2016 06:33 AM

Actually do all m20 engines use timing belts rather than chains?

south26 07-17-2016 12:29 PM

Yes all m20 use a belt.


Andy

aliff01 07-17-2016 07:46 PM

How many kilometers would a new one last before it snaps and what are the signs of it needing a replacement?

south26 07-18-2016 06:28 AM

No signs, just breaks. In miles it is every 60,000 miles or 4 years. If sitting for 6 years and only has 10,000 miles it should be changed.


Andy

BMW_507_4ME 07-19-2016 07:56 PM

Belt/ chain
 
As all know BMW used a timing chain in most motors. Even the chain can be a disaster if you don't keep up with the tensioners. The M50's had a double roller timing chain with a mid engine gear on a bearing to take the stress of the chain. My 740IL didn't have that gear, instead, BMW just used plastic chain guides and as such, many failed as a result. BMW must have saved hundreds per car, but their customers (and reputation) lost thousands. I am sure they saved a few bucks using a belt on the M20's also. My advice is to change your tensioners and / or belt often, even more often then you might think you might need too, cheap insurance IMHO:)

south26 07-19-2016 08:35 PM

Quote:

Originally Posted by BMW_507_4ME (Post 9765988)
As all know BMW used a timing chain in most motors. Even the chain can be a disaster if you don't keep up with the tensioners. The M50's had a double roller timing chain with a mid engine gear on a bearing to take the stress of the chain. My 740IL didn't have that gear, instead, BMW just used plastic chain guides and as such, many failed as a result. BMW must have saved hundreds per car, but their customers (and reputation) lost thousands. I am sure they saved a few bucks using a belt on the M20's also. My advice is to change your tensioners and / or belt often, even more often then you might think you might need too, cheap insurance IMHO:)

I think you might be over stating the fact about the chain. It is not a common problem and yes can happen but not likely. As to saving hundreds? The m20 with the belt was built to be less of a gas hog compared to the m30, which it was. The belt was suppose to deal with the closer specs compared to the 60s tech that made the m30. I have driven a car with the m30 and have never worried about the chain. I have parted 26 BMWs and have never parted one because of a failed chain., 5 of those had a failed belt. So yes a chain guide can fail but not likely.


Andy

BMW_507_4ME 07-19-2016 09:09 PM

Belts VS Chains
 
Well, you missed my point. It was that chains are much better "IF" properly maintained and don't suffer from a poor design. But I am sure after junking so many BMW's you already know what the major design timing chain flaw was in the M60 0ver the M50. I only have 40 years of fixing and racing cars and bikes under my belt, junking must be much harder and I am sure you learn more by tacking one apart, then by making them run, thanks for setting me strait, I will junk my car tomorrow;)


All times are GMT -7. The time now is 10:18 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
© 2001-2015 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms