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General Information => General => Topic started by: the caveman on May 17, 2015, 07:20:08 am

Title: Don't change your timing belt
Post by: the caveman on May 17, 2015, 07:20:08 am
Found this in a 1979 Road & Track tech article:

(http://i356.photobucket.com/albums/oo4/lhomme/Article_zpsn7b8z7t1.jpg)
Title: Re: Don't change your timing belt
Post by: burn_your_money on May 17, 2015, 08:33:05 am
I gotcha covered Marc. ;)

I wonder how long his "lifetime" timing belt ended up lasting...
Title: Re: Don't change your timing belt
Post by: TylerDurden on May 17, 2015, 11:24:09 am
Generally, they last the lifetime of the engine.
Title: Re: Don't change your timing belt
Post by: libbydiesel on May 17, 2015, 11:46:18 am
That's a lot like the 'lifetime automatic transmission fluid' and the 'lifetime coolant' in the vanagon.  I'm pretty sure 'lifetime' is considered the warranty period and that causing the engine or trans to fail immediately after the warranty period is good for parts sales. 
Title: Re: Don't change your timing belt
Post by: 745 turbogreasel on May 17, 2015, 01:10:33 pm
^ so 40,000 miles.
Title: Re: Don't change your timing belt
Post by: the caveman on May 23, 2015, 08:14:03 am
Back at the dealer we used to  change the diesel belts at 160,000 k (100,000 miles for 'mercans). The gassers would be changed when they showed wear or cracks. We only started to look into it when the B2 16V Passats started breaking belts as early as 40,000 k. This was back in about 1991. We weren't a very big dealer but never had an issue with a diesel motor damage from a late belt change
Title: Re: Don't change your timing belt
Post by: the caveman on May 23, 2015, 08:20:37 am
Oh as far as timing chains are concerned, if any of you know about the 2.0 liter turbo  TSI and FSI gasser engines; besides the problems we are having with the timing chain bridge oil screen breaking and going into the spool and intake cam, we are now seeing the cam chains stretching at about 100,000 k on some. We have 3 in the shop this week with bent valves, etc. Mostly on Tiguans with poor (or actually even with the 15,000 k oil changes) maintenance. That and the balance shaft bearings seizing! Lots of work for us, but does not bode well for customers who are out of warranty
Title: Re: Don't change your timing belt
Post by: the caveman on May 23, 2015, 08:23:27 am
"the only type that seems to be service free are gear driven types. " Were the GM engines with the plastic timing gears have a service interval? Saw a couple of destroyed motors with those stupid parts
Title: Re: Don't change your timing belt
Post by: libbydiesel on May 23, 2015, 08:43:33 am
I'm not up on GM engines, but the 'plastic timing gears' I've seen were nylon coated, not completely made of plastic.  Still very stupid from a longevity standpoint but the quiet the valve train some and help sell the crap cars when 'the engine sounds so quiet'...

I have an actual 1979 Mk1 Bentley (not a reprint) and it says, I quote, "You do not need to replace the camshaft drive belt unless inspection shows it to be faulty."
Title: Re: Don't change your timing belt
Post by: RabbitJockey on May 26, 2015, 05:02:27 am
the belts hold up much better than you'd think, i had a 1990 cabriolet 1.8l engine, 170k the belt must have been original, the tensioner actually locked up and the belt was so glazed over it just slipped over the tensioner as if it were supposed to be locked up, i didn't even notice until it started to squeak a little haha.
Title: Re: Don't change your timing belt
Post by: 745 turbogreasel on May 26, 2015, 10:33:16 am
I'm not up on GM engines, but the 'plastic timing gears' I've seen were nylon coated, not completely made of plastic.  Still very stupid from a longevity standpoint but the quiet the valve train some and help sell the crap cars when 'the engine sounds so quiet'...
I replaced a few of those on  GM and Mopar.  Never hurt anything but the $30 chain and gear.
Mostly on original unopened engines with 200K & 20 years on them.
Also, it was easy to  check  for  the chain getting loose anytime the distributor  cap was off, so it never happened to any of mine.
Title: Re: Don't change your timing belt
Post by: clbanman on May 27, 2015, 09:40:04 am
Had a Jeep Cherokee Golden Eagle with the 360 that had the plastic teeth on the large timing gear.  Solid nylon, not just a coating over metal teeth.  Quiet right until the chain slipped over 2 teeth and it wouldn't start.  Didn't do any damage to the engine. 
Title: Re: Don't change your timing belt
Post by: vanbcguy on May 27, 2015, 10:53:06 am
The AHU I bought for my swap had the worst t-belt I've ever seen.  The whole inside of the cover was filled with timing belt fuzz, the belt was about 1/8" narrower than it was supposed to be and there was so much rubber worn off the top you could see the teeth through the 'flat' side of the belt.  Had she not crashed the car it probably would have broken the belt in a few thousand km....
Title: Re: Don't change your timing belt
Post by: libbydiesel on May 28, 2015, 09:00:46 am
A couple years back I was visiting a friend's shop when a fellow on a cross-country trip in an '82 diesel vanagon stopped in to buy some biodiesel from my friend.  I took a look at his engine and saw a bunch of kevlar dust.  This was his timing belt...

(http://i13.photobucket.com/albums/a269/libbybapa/100_2913_zpsu1c1tfr0.jpg)

Total remaining width was 0.4".  His next planned stop was California.  There's no way he would have made it. 
Title: Re: Don't change your timing belt
Post by: srgtlord on May 28, 2015, 12:11:18 pm
 :o Holy moly! Injection pump out of alignment much?
Title: Re: Don't change your timing belt
Post by: libbydiesel on May 28, 2015, 01:30:49 pm
It was actually an issue with the intermediate shaft pulley and bolt.

As Gingy said, "It's a Thong!"
Title: Re: Don't change your timing belt
Post by: the caveman on May 29, 2015, 04:39:53 pm
the belts hold up much better than you'd think, i had a 1990 cabriolet 1.8l engine, 170k the belt must have been original, the tensioner actually locked up and the belt was so glazed over it just slipped over the tensioner as if it were supposed to be locked up, i didn't even notice until it started to squeak a little haha.
Oh yeah. I know that we definitely had a couple of customers with over 300,000 k on their gassers. Those engines weren't interference ones so we never saw a problem, even when they did break. Change the belt ( sometimes not even the tensioner) and sent them on their way
Title: Re: Don't change your timing belt
Post by: ToddA1 on May 30, 2015, 09:44:09 am
I believe the large valve 1.8 heads were interference.

-Todd
Title: Re: Don't change your timing belt
Post by: the caveman on May 30, 2015, 04:05:38 pm
You could be right, however we never saw any motors damaged because of broken belts until the 16V Passats came out.