Rodscobra

Ok I'm doing the timing belt, of course never read any material on how to do it properly!! I put the balancer @ TDC, instead of 45 deg and proceed to remove the tensoiner etc. and the cams flop anti clock wise!!! Have I now damaged the valves? Now what, do I rotate the engine to the 45 deg mark or pull the heads?

F*** ME!!

thanks in advance

Rod

Rodscobra

It's a USA 85 S with 32 valves, maybe a few of them Bent!!!

Rod

EC928NC

I would say relax and breathe deeply. You just created more work for yourself. I'm fairly certain that static spring tension can't bend anything.

First, rotate each cam gear clockwise to where they were (marked right?) and put the belt and tensioner back on. THEN, take the crank lock out, rotate the engine around to 45 degrees and put the crank lock back in (you did use the lock tool right?).

Then don't do another thing until you read, read, read (and for your sake, drop the <$20 for Jim's step by step book).

You're not screwed yet.

RyanPerrella

if the crank is at 45 BTDC then you should be able to move the cams independantly and not risk any of them touching a piston top.

Fastest928

you are ok..are you planning on setting the cam timing?

RyanPerrella

Mark,

I know i should have looked at this when i had the heads off but at 45 BTDC you can move the cams 360 deg and not touch anything correct. all 8 pistons are far enough from the deck height where you can open up the valves up all the way via the cam rotating and not risk hitting the piston tops right?

FlyingDog

Rod, unless you force them, you're fine. Happens regularly. Not all interference 928 engines even have the 45* marks and the cams will always settle one way of the other.

Ryan, 45, 135, 225, 315 you should be safe because all the pistons should be halfway up/down at those points.

H2

Do a search of PorKen's posts and you'll learn a lot about this.

H2

Rodscobra

The balancer is @ TDC.

The passenger cam gear is anticlockwise 5 or 6 teeth away from the TDC mark at the back of the cam gear.

The driver side cam gear is clockwise 5 or 6 teeth away from the TDC mark at the back of the cam gear as well.

I didn't mark a 45deg witness line on the cam gears

Here is the catch!! I losened the belt tension, removed the tensioner, and In my excited state of disassembly, I cut the timing belt with an exacto knife, I thought I could remove the belt easier and speed things up! and not have to remove the balancer! Wrong!! So I guess I need three people to help me install the new timing belt!!

thanks for your help
Rod

Rob Edwards

http://members.rennlist.com/pirtle/tbelt.html

You can do this alone, with lots of virtual help from the crew here.

Apologies if you've already seen the above link!

PorKen

If you didn't have the pinch rollers under the crank gear, and the rear cover, I suppose you could change the belt without removing the balancer...but stock, nope.

He hasn't loosened the cam bolts, so it would not be limited by the slots in the gears.

RyanPerrella

why would you cut the belt? Yeah you can get the belt off without removing the balancer, but how the hell did you think you were going to get the new belt on? What cut the new belt, slip it on and staple it or tape the belt together?

When doing the TB the first thing you do is set it to 45 deg, lock it then start disassembly.

If your crank is at TDC then you may have bent something, if it was at 45 then you shouldnt have an issue.

RyanPerrella

and this should go without saying, but you CANNOT RUSH THIS STUFF! Its procedural, there are many write ups on how to do this job, and NONE of them have you cutting the old belt.

FlyingDog

The 45* mark is unnecessary. If you don't screw up and force the crank or cams to turn, you won't bend anything either way.

RyanPerrella

no if its all in time and you simply swap the belt you can do this job anywhere really. But things do happen, if the factory suggests you pull the belt off with the crank at 45 deg btdc then why wouldnt you put it there? If its not there when you turn the car off, you simply rotate the engine a maximum of wo revolutions until you are where you need to be.

Again, this is never something you rush