timing belt tension question

[leaf...]

okay, so i just bought this car. ended up having to put a new clutch in it. got te whole thing done the take it for a test drive. 2 minutes into the drive it looks like i'm behind the wheel of a mobil fog machine. headgasket is blown. so i put the new gasket on, put a new timing belt and all that on. i timed it right and everything. started the car up to mak sure everything was ok ad lt it run for a minute or 2. looked at the car a few hours later and saw that my timig belt was really loose. so i put a wrench on the crank and turn it ever so slightly and the tension comes back. did i do something wong? did it skip timing? is my tensoner bad? i really need to get this thing on the rod whithin the next couple days so any help would be great.....

 

[talon1979]

I am not sure how loose your timing belt is, but it is common for the timing belt to seem pretty loose after the car has been sitting for a little while. After I changed my timing belt I wondered the exact same thing. As long as the timing belt is not loose enough that it will jump teeth on the cam gears I think you should be ok, but again I am disclaiming myself since I don't know how loose it is getting.

 

[Defiant]

When stopped, the cams can be at a point where the valve springs are trying to turn them toward each other, which will give a loose appearance. However, with the number of teeth engaged on a cam sprocket, it's okay once the crank starts to turn. Yet another good reason to keep a cover on there.

 

[crankbender]

Did you check the tensioner when you had the tbelt off? mine went bad and the belt started bouncing off the bolt under the oil pump and grooved the tbelt.

 

[leaf...]

ok, so basically it was a fluke thing? i thought my tensioner might have been bad but it seemed fine when i took it off. yeah, cuz it was loose when i stopped the car but as soon as i turned the crank the slightest bit with a wrench it tightened right back up and hasn't done it again. so this is ok? am i good to put the rest of it back together?

 

[BUCK]

Originally posted by leaf... ok, so basically it was a fluke thing? i thought my tensioner might have been bad but it seemed fine when i took it off. yeah, cuz it was loose when i stopped the car but as soon as i turned the crank the slightest bit with a wrench it tightened right back up and hasn't done it again. so this is ok? am i good to put the rest of it back together?

- Man do yourself a favor - RECHECK the Tensioner Setting before you put all the covers back on for God's sake - the BEST way to check Tensioner setting is with the Grenade Pin (small drill - heavy paperclip, etc) - if Tensioner Push Rod is turned correctly you should be able to reinsert Pin IF tension is CORRECT - if Tensioner Pin is not oriented correctly I'd go with the measure the gap with drill bit method.

- It IS ROUTINE for the T/Belt to have a "slack side" - that's why the Tensioner is there - But we CAN'T assume yours is set correctly - CAN"T assume your Eccentric Pulley hasn't slipped or was incorrectly Torqued - ETC>>> ALWAYS assume the WORST CASE with these things & you'll be SELDOM dissappointed - this is a BIG deal unless you enjoy pulling Heads as a Hobby...

Leaf: is my tensoner bad?

Well that's about a minimum $400 question isn't it? - YES you should have changed the damn Tensioner & ALL the Tensioner Pullies if they were original... You may well wish you had by next month...

 

[leaf...]

Originally posted by BUCK
- Man do yourself a favor - RECHECK the Tensioner Setting before you put all the covers back on for God's sake - the BEST way to check Tensioner setting is with the Grenade Pin (small drill - heavy paperclip, etc) - if Tensioner Rod is turned correctly you should be able to reinsert Pin IF tension is CORRECT - if Tensioner Pin is not oriented correctly I'd go with the measure the gap with drill bit method.

- It IS ROUTINE for the T/Belt to have a "slack side" - that's why the Tensioner is there - But we CAN'T assume yours is set correctly - CAN"T assume your Eccentric Pulley hasn't slipped or was incorrectly Torqued - ETC>>> ALWAYS assume the WORST CASE with these things & you'll be SELDOM dissappointed - this is a BIG deal unless you enjoy pulling Heads as a Hobby... & YES you should change the damn Tensioner & ALL the Tensioner Pullies if they were original!!

ok, explain that first part in idiot terms. how do you check the tensioner setting?

 

[BUCK]

Go out to your car - spin it over with starter a few times - set crank marks at TDC just to use the same reference point - & check Tensioner setting like you did when you put the new Belt on.

There are at least 2 ways to check tensioner setting.

if Tensioner Push Rod is turned correctly you should be able to reinsert Pin THRU TENSIONER & TENSIONER PUSH ROD IF tension is CORRECT -

if Tensioner Push Rod is NOT oriented correctly I'd go with the measure the gap with drill bit method - From VFAQ...

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[leaf...]

ok, i understand it now. about the drill bit method, how much of a gap should there be? i'm at college right now so i won't be able to check the car until tonight. i just need to get this thing done so i can finally drive it.

 

[BUCK]

From:

http://www.vfaq.com/mods/timingbelt-1G.html

Which I'm sure you've memorized by now... What they neglect to tell you is that the gap can be measured by reinserting a small pin thru the "hole in Tensioner body" & Tensioner Push Rod IF setting is correct & Push Rod is so oriented ... the Tension setting is Correct if the Pin is LOOSE (not captured by Tensioner & Push Rod) - or of course Tension Settin is Correct if Pin can be reinserted thru the "hole in Tensioner body" & Tensioner Push Rod.

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[leaf...]

ok, now this makes pretty good sense. i'll redo the tensioner tonight and see what happens. hopefully all will go well. thanks for all the help.

 

[talon1979]

I am not going to gurantee this, but I would imagine your car is just fine if everything was installed well. A loose timing belt after the car has been sitting is a common thing.

 

[BUCK]

Talon 1979 is very correct - it may be dead nuts - it's just that this area calls for a high level of PRUDENT DUE DILIGENCE - Actually I reccommend everyone do what "leaf" did - Install belts & set it - run it - recheck Tension settings - THEN put the freaking covers on! I editted my posts above for clarity & nomenclature but nothing really changed. This thread should come in handy about 3 times a freaking day...

 

[markgholland]

There is a possibility that when you were tightning the tensioner, that you didn't tighten it enough so it started to loosen. You know, the tensioner that you move counter-clockwise to actually tighten the belt? This happened to me once and I had to have the car towed back to my house when I poped the hood and realized that my belt was slipping off the cams... It's safe to just double check it to make sure everything is lined up correctly. Time it, retime it, and time it again. Don't just do it once and say, "good enough." There is never a good enough with inference engines....

 

[leaf...]

yeah, i mean, i ran the motor for a little and everything was fine. but as it goes with DSM's i agree, don't just do it once and call it good. i'm going to redo the tensioner and pulley tonight just to double check. i can't wait to finally drive this damn thing.

BUCK: i completely agree with you. this thread should come in handy quite often for people. thanks again for all the help.

 

[BUCK]

You know, the tensioner that you move counter-clockwise to actually tighten the belt?

Yeah - there's actually a pretty snappy Torque value on the Eccentric Pulley Fastener - as well as the even smaller "Special Bolts" that hold the Tensioner on - which BTW is why I don't concur with snatching the Tensioner on & off to re-compress it in a vice as some guys espouse instead of using the Allthread tool to recompress the Tensioner - I used the soft slow-setting Blue Loctite on all of those Fasteners.

 

[leaf...]

just an update. got the car all together last night. i've been driving it today and it runs great! runs as good as new. thanks everybody for the help.

 

[project94tsi]

k sorry to jack the thread but my timing belt is doing the same thing and it is also drifting towards the drivers side of the car. What could cause that.

 

[steve]

The timing belt walks off the sprockets because of uneven tension on the belt. Usually this is caused by a worn tensioner arm pivot but any thing cocked like a bad pulley will cause it.

Steve

 

[dsmkid4g63t]

Time it, retime it, and time it again. Don't just do it once and say, "good enough." There is never a good enough with inference engines....

I support this, just rebuilt me head, did a headgasket, arp studs, all new timing components, timing belt and balance shaft belt, ran the car last weekend, let it sit, this weekend im going to check the timing, re-run the car, check the torque on the head, re check the timing....then put the covers on!

Greg