Zirconocene

I hope folks on here can help me with getting the timing to a better state than what I started with. Never done this kind of work, and I'm not sure what the pitfalls are.

Here's the situation: During some other work on the car I found that the balance shafts were set up completely wrong. What is completely you ask? Not only were the shafts not set correctly for timing, but the gears themselves were installed reversed, meaning with the flange facing out. Ugh. I was going to call it a day at that point, as apart from some serious shaking during driving, the car runs pretty well. Further reflection, however, told me that I should really take a look at the timing situation while I had everything apart. The water pump looks new, as does the automatic tensioner, so that's pretty good news. (Side note, though, is there a problem with these cars where a metal impeller on the water pump will eat into the block, similar to the 928?). I don't see any leaks from coolant or oil seals, so I feel OK about not messing with those things and leaving them as is.

Here's where I need help, as I've watched a bunch of videos and tried to read as much as I can but most of the tutorials are for earlier cars. I can get the camshaft lined up with no issue, there's a nice mark that I can match up with the notch on the back plate. For the crank, though, I'm having a really difficult time understanding where all the marks are that I should be looking at. It seems to me that the 2 reference marks that I need to pay attention to are the OT line (which is sort of hard to see) and a machined divot which I can see on the flywheel or pressure plate through a hole at 6 o clock on the bellhousing. Is that right? For the OT line, it should be dead nuts aligned with the tab on the bellhousing, correct? For the divot, it should be exactly centered in the inspection/view hole, correct? Since it is not centered, but the belt is off, is there any issue with moving the crank counterclockwise to get things lined up? As there's no longer a bolt on the crank gear, what's the recommendation for how to move the crank effectively?

Finally, since my car has an auto tensioner, do I need to play games with lining up the cam gear once I get the tension back on the timing belt? I know the crank won't move, since I'll have the lock on there but, since it looks like everything has been about a tooth off since I got the car, I'd like to make sure that I get this right.

Thanks for reading, and thanks in advance for help and guidance.

Cheers

V2Rocket

the marks on the flywheel dont usually precisely line up to the markers.
most certain way is to stick a wood dowel in a spark plug hole and turn engine until TDC.


if the timing belt is off, lock the timing tensioner all the way slack. set the cam sprocket to line up with the notch on the gear housing.
youll need to feed one side of the belt behind the tensioner arm before bolting the tensioner on. make sure the "tension" side of the belt is as straight and tight as possible (cant pull a tooth off that side).

cam gear shouldn't move much if at all when you release the tensioner to tighten the belt.

then set the balance shaft belt but don't be surprised if the TDC marks are as much as half a tooth off. on the front of the BS gears you will see a "0" stamped...the gears can go on 2 ways so the upper shaft should be set with 0 to 11o'clock and the lower shaft gets placed with 0 at 5 o clock.

Zirconocene

Thanks Spencer, that's very helpful. I went out and messed around a bit and got the marks lined up well but I will take your advice and test with a dowel.

I feel pretty confident with how the balance gears are supposed to look and interact with the thrust washers (which was enough of a $#!+show that it amazes me the gears were tightened down; I don't know how the PO got a counterhold as the thrust washers were set up wrong, in addition to the gears being flipped around). It's good to know that there might be some slop in the alignment of the BS marks. Anything has to be better than what I started with.

Cheers

V2Rocket

The TDC marks will indicate TDC but i was just meaning to say that it may not exactly line up on the marks.

Gage

Keep in mind that on the s and s2's, the camshaft to cam gear index is variable. The full and proper way to set the cam timing requires removing the cam cover and the ability to measure valve lift at the cam lobes.

Van

This might help:

V2Rocket

this is true, but most of the time if you just put the cam gear on the "propeller" and line up the washer/bolt wear marks you're pretty much there.

Zirconocene

Thanks Van, that is also very helpful.

I think the right choice is to stop avoiding the extra work and go through and check everything, given the state of how things were done previously. It will give me a chance to inspect the chain guides, as well, as that was supposed to have been done previously but everything is now suspect.

Is the setup difficult for the valve lift indicator? I've never done this kind of work and it's a little intimidating, tbh. I think I can set up the TDC indicator; how long a probe do you need for it? Will the standard length be enough? Same deal with the valve lift indicator?

Van

I believe I used a 4" extension on the TDC indicator. For the intake valve indicator, I made a little "bracket" out of a long bolt that I could thread into a hole. I also used a piece of thick steel wire to make an extension for the plunger so it could touch the top of the lifter. Be patient and I'm sure you'll be able to figure it out.

V2Rocket

S2 spec is something like 0.75mm intake lift on cyl 4 when cyl 1 is at TDC (or is it TDC@4 and valve lift@1?)...
but i'd be tempted to slam it as far advanced as the gear allows (not much) as an experiment. someone on Pelican tried that a few years ago and reported positive butt-dyno gains.

Nicks2

First couple of times I did this with dial gauges it took a few goes to get the process down. +1 on making a steel bracket to bolt to the head. For me setting up the gauges so they give repeatable readings was/is the hardest part, the more solid the gauge mounting the better. I marked my cam sprocket and crank pulley at TDC when I thought I got it right. Good luck!