Timing belt fun - a year later

[88pathoffroad]

I've had some power problems(no high RPM power, popping at light throttle, sometimes it would die when I hit the gas) with my VG30i since last time I tore it apart and put a new timing belt on, so I finally decided to go back in there a year later. By this time, I'm thoroughly tired of it running crappily. I took it all back apart to see what I did wrong.

 

This is what the front end of the VG30 engine looks like with the timing cover off and no belt.

 

 

Evidently, I was off by about one tooth on the crank gear when I put my new belt on. This time, I very carefully checked to find top dead center for the #1 cylinder by taking a long piece of #3 copper ground wire(ground the end down and sanded it carefully to prevent scratching my piston) and moved the crank around to find exact TDC so I could set the timing correctly. The cams were both advanced one tooth too far. The timing marks for the cam gears are easy to see and compare.

 

Here's the bottom side.

 

And here's the freshly punched timing mark that the Chilton's book said was already there. When I got underneath and looked, there were no marks of any kind to help me align the crankshaft, so I found TDC and punched a mark on the edge of the engine where it should have been. Grrrr...

 

So, I took the belt back off, am in the process of getting a new belt(insurance against having to do it again) and a 180 degree thermostat(I had a 190 degree 'stat in there, and it seemed to run hot to me), and that's where I sit at the moment. I'm cleaning and repainting the timing cover and pulleys so they look good.

 

Just thought maybe people would like to see what's involved with changing the timing belt.

[Diesel Boy]

Hey thats interesting stuff!!

No timing marks on the fly wheel??

Thats a common place for them, and they usually have a degrees marked either side of of TDC!!!

I wonder how they set the ingnition timing??

Suppose its done by the computer for the most part.

Just as well your a clued up kinda guy!!!!!!

Pete.

[Guest Drakar]

This was very helpful. I did my timing belt about a year ago and ran into the same problem, not finding that timing mark. I looked for awhile, left and came back a different day and looked again and never found it. I wished I could have learned or thought about your method a year ago. I just may have to tear it apart again to do this. I have noticed a loss in power and acceleration in mine. Great idea and information.

 

Drakar

[MatterHorn]

yeah ... there were no marks on my first motor either ... I did the same thing and made a punch mark at where it should have been ...

 

 

never had to use it though ... a year later the balancer sheared and damaged the end of the crank shaft - I welded it as a temp fix until I got a new motor ... funny ... my new motor has the marks ... when I swapped the timing belt covers I noticed it ...

[lgranch]

Well I changed the timing belt on my 91 pathy using 88's original thread. I did have a mark for the crank on mine. It was very faint, but there. The only way I found was to put the #1 at TDC and feel very carefully for the mark. I then pinted it so that I could see it as I put things together.

 

What I posted at the time was that the old belt had the right cam off by one tooth. The left cam was fine. I corrected everyhting when I put it all back together.