Question on the balance shaft alingnment marks

[VaSteve]

Ok did the belts today. On final check, I think I did the balance shaft belt wrong. I believe the alignment is off. The car has not been put back together....

Clark's says:

Sometimes you'll find that the notches on the sprockets don't line up exactly. This is not uncommon. About half the 944s I've seen don't. However, with one sprocket dead on it's alignment mark, the other sprocket should be no more than about 1/2 tooth off. If it's out of alignment by 1 tooth or more then it should be realigned.

I cranked the engine around by hand so that the top balance shaft is aligned by the notch in the back (I won't tell you what I used to align it ). However the engine is not at TDC (at least I'm pretty sure it's not) The lower does not liine up with the tab when the topis lined up.

What do I need to do to fix/fininsh this? I assume put the engine back at TDC and loosen the balance shaft belt enough to rotate these two shafts to where they are supposed to be. Retighten. Is that it?

I have visions of flywheel locks and other horrible rework.

[NKN84944]

The flywheel lock should not be necessary as long as you can keep the engine at TDC when you are aligning the shafts. All you have to do is align them properly and tighten them back up. Below is a pic of how it should be aligned. Hopefully this is enough to answer your questions.

[VaSteve]

Yes, that should do it. I was using the wrong mark to align these...

Oh and how is 210 N-m at the crank shaft pulley acheived by hand? I must be weak....

[wizkid918]

either a cheater bar... or lay down and use your foot

[Moneyguy1]

Not off topic, but wouldn't it have been nice if there were a hole in the cog wheels (pulleys with teeth) and a threaded hole in the block so the pullys could be held in alignment with a bolt during initial installation of the belts?

Just the engineer in me....at least it would have eliminated the need for the flywheel lock....

[VaSteve]

There really needs to be something to hold those balance shafts in place while tightening the belt. I had my wife hold the belt in place at the top while I got the bottom lined up and the blet retightened.

Since I had already tightened the belt properly before I loosened it to realign the shafts, I used a trick to avoid remeasuring the deflection of the belt (with the Arnworks tool). I laid a piece of masking tape across the metal part of the eccentric nut and ran it out to the plastic housing. I then used some fingernai polish and painted the edge of the tape, which created a nice edge. After realigning the shafts, I made sure the marks lined up.

[SoCal Driver]

You can rotate the balance pulleys with the belt on but totally slack. Trick is to have the lock nut on the tensioning pulley snug and as much slack in the belt as the tension pulley position will allow. You can "walk" the belt around the balance shaft pulley. Turn the pulley so the span of belt between it and the crank is snug to check the alignment. Tighten the tensioning pulley leaving about a 90 degree twist in the long span at the top.

[924Sman]

I agree Bob. Need a way to hold those 2 pullys in line. I keep trying to get the bottom shaft in line and tensioned properly but every time I set the tension the shaft moves off a tooth. If there is a way to keep these BS from moving I would like to know how.??

[Lawrence Coppari]

The top shaft always stays put. The lower one can give trouble. Like SoCal said, you can slip the belt on the pulley and move it in relation to the pulley. Lower shaft will tend to rotate as you tension the idler nearby. Compensate for this when you first postion the belt on the pulley. Works for me.

[924Sman]

I guess my talents failed me. I tried to offset the alignment as you mention but still moved to much. I just need more play time with it!

[Lawrence Coppari]

I assume you are aware that the rotation of the tensioner for the balance shaft is clockwise (CW). For the cam belt tensioner, the rotation of the tensioner is counter clockwise (CCW).