Timing belt walk

[T3RR0R15T1C]

Alright, so I have a 4g63t. Greddy timing belt, balance shafts have been deleted, and I have a manual timing belt tensioner.
Here's the issue, I have the timing set perfectly, everything aligns. I'll go to start the car and run it for 10-15 seconds. I'll turn the car off and check the Timing belt. And it starts walking off the right side of the cam gears. I'm truely at a loss at what it could be. My buddy and I have tried countless things to fix this issue.

Things I've done:
-Cut the timing belt cover so it doesn't rub.
-Check tension over and over again
-made sure everything is aligned.

What I think it could be:
my thought on this is that the tensioner pulley is bad.
I just want to know if anyone else has had this issue and what they did to fix it.

 

[T3RR0R15T1C]

Here is what it's doing. This is after it's been centered on the cam gears.

 

[estoyaqui30]

Walks off as, if you leave it running it will actually come off? Mine doesn't run centered, but flush to the outer edge and just stays like that.

 

[tmoney20g]

I've heard of people putting the lipped side of the idler pulley on backwards, so maybe check the orientation of that ? oh, and the disc between the crank pulley and balance shaft pulley as well.

 

[sbiggi]

Assuming the tensioner pulley is square to the block. I believe the belt is basically located by the cog on the crankshaft

 

[enos1010321]

1. Is it a six bolt or seven? If it is a 7 did you place all of the parts on the crank in the correct order? There is a trigger plate and I believe the belt is aligned to the crank sprocket. So if the crank sprocket is not in the correct position you will have issues.

2. I have seen engines before where the belt rides on the outside edge of the cam gears. If you leave it running will it continue and fall off or will it stop as you have pictured?

3. With a manual tensioner you will really need to keep an eye on your timing belt. There is no adjustment and as the belt flexes with speed and load the manual tensioner can cause slack in the belt. I would not suggest a manual tensioner for a daily. Are you reving the engine and the belt moves or are you just letting the car idle? If the belt moves during the increase of RPM's and not idle, I would think the manual tensioner is the cause.
4. If you really want to check if it is the manual tensioner, switch out a regular hydraulic and see if your issue disappears.

Not to alarm you but I actually had an issue like this when my rear idler pulley mount was cracked in the block. The one between the oil pump and the intake cam. It was not strait and would make the timing belt start hitting the block and fray the belt after about 5-10 minuets of driving. There was nothing behind it so I drilled and tapped it deeper and it fixed my issue. I would check all of your pulleys for squareness also.

 

[T3RR0R15T1C]

Enos- It's a 6 bolt, but I really do think it's an issue with the pulley.
And no it's not being revved at all, this is sitting at idle, I am considering switching to an auto tensioner, because I do intend on daily driving the car.

TMoney- that's not the case here. All the pulleys are on correct, my buddy that built my gst came and check it out. And he's even stumped on this.

I'm going to pull the pulleys and inspect them to see if this Is the cause and go from there.

 

[Cynxe]

My belt sits to the side, I used to wonder about that. I used to drive it and stop and look over and over again, but it just kinda sits flush with edge of the gear.

 

[luv2rallye]

If that's all the further it goes to the side when running or stopped I wouldn't worry about it, it's ok. As long as it doesn't go over the edge. I'd strong suggest the auto tensioner though.

 

[T3RR0R15T1C]

If that's all the further it goes to the side when running or stopped I wouldn't worry about it, it's ok. As long as it doesn't go over the edge. I'd strong suggest the auto tensioner though.

Here I'll post pictures to.further illustrate. But it is walking off the side of the cam gears.

 

[luv2rallye]

Ya that is not good and needs to be resolved (your first picture didn't show it going over the edge). First you need the auto tensioner. You may then need a new tensioner pulley (assuming everything else is ok).

Very rare and this probably isn't your case being a 6 bolt (check other things first - this would be a last senario) but: Mitsu changed vendors a couple times on the tensioner pulley where I had to actually find an older vendor's tensioner pulley (at another Mitsu dealer) to get mine to keep the belt centered (however mine is a 2g 99 GST). As I recall they didn't even change the part number with the new vendor which took me a while to figure out. But the newer one was just slightly different (had to look very close with them next to each other). I think the distance from the surface where the bolt goes through - to the pulley edge was changed. It still ran in the center (the way they did it, if I remember right, was make it cheaper by thinning that surface the bolt goes through) but the vertical force then changed positions just slightly which made the belt run not in the center (just slightly off). At least that's what I concluded since that's the only thing I changed which instantly corrected the problem. As I recall a color on the pulley might have changed (since it was a different vendor) but it looked exactly the same so you wouldn't think anything of it. It wasn't until I installed it, I noticed the belt moved over so then I compared the pulleys side by side and looked and measured very closely and found them just slightly different.

 

[pauleyman]

Which tensioner pulley are you using?

 

[rough]

The part of the belt on the rear cam gear is way further away from the head then at the front!
By that view alone you can tell that it's probably going to be the idler pulley, as the front of the belt looks ok compared to the rear overhanging!

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[1990TSIAWDTALON]

I have seen a non OEM idler pulley without the lip on it which let the belt walk so check that if you haven't.

 

[maddogxx]

mine did this and it ended up being the tensioner pulley going bad, I replaced it and the belt stayed right in the center.

 

[pauleyman]

There are two different tensioner pulleys also. They are not the same 90-99.

 

[T3RR0R15T1C]

Ya that is not good and needs to be resolved (your first picture didn't show it going over the edge). First you need the auto tensioner. You may then need a new tensioner pulley (assuming everything else is ok).

Very rare and this probably isn't your case being a 6 bolt (check other things first - this would be a last senario) but: Mitsu changed vendors a couple times on the tensioner pulley where I had to actually find an older vendor's tensioner pulley (at another Mitsu dealer) to get mine to keep the belt centered (however mine is a 2g 99 GST). As I recall they didn't even change the part number with the new vendor which took me a while to figure out. But the newer one was just slightly different (had to look very close with them next to each other). I think the distance from the surface where the bolt goes through - to the pulley edge was changed. It still ran in the center (the way they did it, if I remember right, was make it cheaper by thinning that surface the bolt goes through) but the vertical force then changed positions just slightly which made the belt run not in the center (just slightly off). At least that's what I concluded since that's the only thing I changed which instantly corrected the problem. As I recall a color on the pulley might have changed (since it was a different vendor) but it looked exactly the same so you wouldn't think anything of it. It wasn't until I installed it, I noticed the belt moved over so then I compared the pulleys side by side and looked and measured very closely and found them just slightly different.

I was going through some boxes last night I had for the car and I found a brand new gates racing timing belt kit. I ran the numbers and it's for my 6 bolt. I still intend on getting an auto tensioner just for daily driving.

 

[pauleyman]

There are definitely two different pulleys. Even gates shows two different tbelt kits.

 

[estoyaqui30]

I guess the 2GBs are different? My idler pulleys don't have a lip on them. Mine is a 99 and the belt runs flush to the edge. It has run just like that consistently since I built it.

 

[dsmvenge]

Had this problem. Turned out to be a worn bushing on the tensioner arm.

 

[Rideordier1]

is that timing belt not on backwards?? arrows should face the rotation of motor not front of engine? and if the belt is riding just on the inside but it is flush with gear should i be worried about it or is it fine so long as it doesn't get chewed up