100 000Km Service | Leaking Water Pump | Timing Belt

WD40 is water-based

Use only INOX or LANOX (lanolin-based).

 

To-Do List

When I first installed all the new bits and rotated by hand every thing was good. Then my error with the crank sprocket sliding forward and must have placed a fair amount of pressue onto the 'weakest link'. No rubbing of timing belt before I dismantled everything.

Yep, tensioner is new as with all other parts. I will dismantle again and replace both upper and lower idler pulley locating bolts to block (as I have new ones here). I tried to measure the 'trueness' of the idler pulleys but a simple vernier is not enough equipment to measure everything. As suggested previously the upper idler pulley may be out of square causing the belt to move backwards all the time.

I'll provide an update soon...

 

Upper pulley would have to be bent downwards to make the belt track like that. You can't make it bend that way with the timing belt, as the only way that pulls is up...

Have you tried cranking it for an extended period, like 20 complete revolutions? Might start tracking right after that

 

To loosen tough bolts, mitch suggests 'Penetrene'

Tried and proven penetrating oil used by fitters for years. My old boy used it 20+ yrs ago and still swears by it.

As for the belt, is it directional? Are the teeth orientated in such a way as to push it outward on the pulleys? Is it back to front? (just a guess)

 

Are they new Idlers? Perhaps worn bearing/belt tension is causing the top idler to mis-align

 

Examining your pics, I can offer the following:

1. Idler studs may be bent, although they'd have to be bent inward to cause the problem, IMHO.
2. Crank sprocket appears to be the only gear aligning the TB correctly - but it has a rear spacer to align TB
3. Auto-tensioner may be faulty/idler out of alignment OR mis-seated?
4. Timing belt worn or damaged? Check tooth height with a vernier - inside v outside OR turn TB around OR test theory with old TB?

 

Idler Bearings & Studs

Hi all,

Well, this just gets better doesn't it

I again removed everything: Tensioner, idler bearings, timing belt to see if I could see anything which had been mis-aligned or even bent? But, conducted several measurements on various new parts just removed and all seems to be straight, at first I thought the tensioner arms was a little out, but it seems O.K. too, so I'm stuffed as to what the hell is going on.

I also tried to remove the idler bearing studs, but man, they are stuck fast indeed - even using the two nuts together method and no-go! I'll have to purchase a pair of lockpliers and give it a go with them. I did put the vernier straight edge along them and they seem fine?

Yep, I'll put back the old parts and see if I can get it to play ball.

I'm starting to get the feeling I'm in 300ZX hell...

The only thing keeping me going is you guys - so a big THANKS to you for your help

Just a thought: I'd be rather miffed if I put all the old stuff back and it's fine.

 

Extended Cranking - Belt Tracking

Hi Chrispy,

Yep, this afternoon - got the missus to 'man' the key and I watched it while she cranked it over. At first just a few revolutions to see what happens - the bloody belt moved towards the back. So, expecting it to re-align itself, I said to the missus give it a longer go and still in the exact same spot as the pictures. Then, I gave it a longer run of about maybe 20 revolutions if that and still the same???

So, I'm going to replace the idler studs - when I can get them out and mess about from there.

Cheers, dude.

 

New Parts

Hi Baron,

Yep, all new parts there mate. The only thing I didn't initially replace was the idler studs as they had been replaced some time in the past and looked new. But as soon as I can get them out I'll replace them too. So, back to the drawing board for me...

Bit stumped at the moment!

 

Miffed is not a word I'd use right now:nono:

 

Timing belt only goes one way doesn't it. Memory again, but I thought mine had marks on it, which lined up with the engine marks, but really can't see it making any difference

 

Longshot but maybe when the crank sprocket moved

forward the belt would have been held in position by the cam gears but would have moved forward where the crank sprocket is and this resulted in the timing belt being permanently distorted causing your present problem. I would be trying a new belt or at least trying the old belt to see if you get the same problem. Good luck with it.

 

looking at the pics closely, I'd dump the belt, try the old one, then get a proper one

 

Yes SIR - Miffed!

Ha, Ha, that made my day Baron.

I'll put the old stuff back on in the next few days - after the build up steam has released from my ears and the mad red eyes have gone. Doing stuff all mad is not good eh.

Oh yeah, I did have a fantasy which involved a hammer at some stage.

Did someone mention I have the patience of a saint.

 

Timing Belt - One way direction

Hi Baron,

Yep, this particular one has small arrows that I'm sure are meant to identify which direction the belt turns in. In this instance, there are three which all point to the right (incidently towards the brand name, which will also be in the correct alignment and facing out so you can read it) for the direction of engine rotation.

The belt is the Gates Racing version, which is meant to be very strong. I spent quite a bit extra on it.

 

I agree

Which is reason I suggested "Timing belt worn or damaged? Check tooth height with a vernier - inside v outside OR turn TB around OR test theory with old TB?"
New Gates belt may be turned around to test theory but would require re-marking it. Try using old belt .... easier. :zlove:

 

Deformed Timing Belt?

Hi guys,

Yep, I'm starting to think the timing belt is damaged in some way (defromed with the previous error) as the parts I removed all 'seem' to be O.K. and chatting with some other mates at work and this would appear to be the only remaining thing - timing belt deformed in some way. Funny, as I look closely at it, there doesn't appear to be anything obvious. But, I'm sure the belt was never meant to be "tested" in the manner in which I gave it a go

I'll conduct some measurments on it and ponder some more, update tomorrow night.

Thanks guys.

 

Tensioner Mis-Aligned

Hi all,

Well, I must report in - good news finally.

As mentioned earlier, I had dismantled all the parts again to see what was going on and was rather stumped with the belt alignment issue. Today after removing the studs for the idler pulley bearings I had a close look at the block and the tensioner mounting surface. Guess what I found there...

I found a flat washer was still located on the stud mount for the tensioner, how did that get there? Anyway, I quickly mounted up all the new stuff (including the timing belt) and conducted a quick rotation check by about 120DEGS either side and confirmed that the belt wasn't moving out at any strange angle or amount and it was tracking perfectly, Yeaahh.

So it would appear at this early stage that the flat washer was on the inside of the tensioner (between itself and the block mounting face) creating a slight angle to the tensior to the belt and causing it to skew off centre.

I'll do a motor start tomorrow and see if all is good.

Good day today.:biggrin:

 

Great news and good of you to post the reason for

for the problem. A lot of people don't and so we don't get solutions to problems that we can refer to when doing searches. Good luck with your car.

 

Reporting In

Hi Zedophile,

Yep, I just had to report in as I received so much assistance from others on the forum, so I thought it my 'duty' so to speak.

And, as it turned out the fault was my own doing, especially trying to keep the job going by working by artificial light and didn't see the grease stained flat washer still on the stud.

So, a BIG thanks to all who assisted so quickly when I was in need.:thumbup:

I just have to get my finger out and assemble the rest.

Cheers.