divil

I'm part of the way through the timing belt job. I had a hell of a time getting the viscous fan bracket off but it finally succumbed to my stubbornness today

I am now confused about setting TDC though - I lined up the crank pulley mark and after some fiddling I was able to get the cam lock in place while the pulley was still very close to the mark. I know they can be off a bit, so this is OK. But even with the crank locking pin installed, I can still rock the crank forward and back a little. I did this with the cam lock bar on so I wasn't sure if it would move more with the bar removed.

The belt is still on so maybe the small amount of movement I saw is just the slack in the belt?

My main question is - when the crank pin is installed correctly, is the crank locked 100% in place, as in, no movement at all? If so then I haven't got it properly installed. I tightened it by hand as much as I could, then used a wrench until it was getting difficult to tighten it any more.

Here is the best pic I could get of it...I can still see some thread but I don't know if it's supposed to go in much further:

MP4.2+6.0

once it is bolted in, I don't think you could dynamite the crank even a tiny fraction of a degree. I pulled a head so had it way torn down to the piston crowns and it wouldn't budge. Ditto when I did just a belt job. Mine is a 4.2. It also threaded deeply in relative to your picture and question. Maybe you don't have it exactly lined up yet where you can drive it way home into the hole in the crankshaft?

By the way, clutch fan is way easier w/ the factory tool if you didn't buy/rent it. Took me the better part of two hours of fiddling time #1 w/ out it, and like 5-10 minutes w/ it when I pulled the head the second time (for unrelated reasons to the earlier belt job). I have done mine w/out pulling the front clip forward, so getting that fan out of the way to do the belt, at least on a 4.2, is critical.

divil

Thanks. I'll try rocking the crank back and forth and see if I get the tool to fit better tomorrow. The belt is still on so I should be ok as regards timing.

Well it wasn't the lack of the special tool that made it so troublesome, it was the allen head bolts. They were some of the stuckest bolts I've ever seen. I had already damaged 2 of them. In the end I had to hammer the allen key in to the bolt head, then I had to use the hammer to actually turn the key. I hammered quite a bit before it moved, and even then I still hammered it about a half turn before I could loosen the bolt by hand!

MP4.2+6.0

on those as I found by job #2, the trick was definitely to loosen them BEFORE disassembling any belts. That gives a lot of friction help getting them off one at a time. Otherwise, holding one that tightens with one wrench while trying to loosen another (my job #1 method) is very slow going.

I also replaced mine as part of the job due to that tendency to round off the internal allen hex inset.

divil

OK got that sorted thanks. I guess had hadn't checked the crank after the last few turns of the locking pin...checked it today and it won't move a bit. Belt, pump, idler and tensioner are now off. Now comes the valve cover gasket/cam seal detour.

SloopJohnB@mac.com

Many people use a small screwdriver or pin punch in that TDC tool hole to make sure the hole in the crank is lined up...then use the TDC tool and run it in with a wrench.

As for getting stuck socket head cap screws out...I swear by an impact driver...used this on many motorcycles with socket head cap screws and those damnable Brit Triumph bikes with phillips head screws.

jseklund

Sorry to show up late to the thread, and it seems like you've got this worked out - but I think that may be one of the best photos of the crankshaft pin in place that I've seen yet. Could be helpful to others looking for where it goes.

The Bently says that you MUST feel for the hole to make sure it's lined up. I can't seem to get my hand in there usually, and I don't wanna lose a finger - so I use the screwdriver method mentioned earlier. I've always been pretty well lined up, but I use a socket to tighten the thing down before I'm done.

Huskerbob

am I wrong or did lining up the mark on the crank (front) not also align the crank locking pin hole? I didn't have to feel around or use a punch or screwdriver to install the crank lock and I screwed it in by hand.

jseklund

You are not "wrong" per se - it should work like that, but the timing can get sloppy as the belt stretches and time goes by - it may be off a little. This is the reason the mark should NOT be used to set timing and the pin should be inserted. The marks are a guide, but are not 100% reliable and accurate.

SloopJohnB@mac.com

Timing belt has nothing to do with the TDC tool...what happens is the harmonic balancer integral to the crankshaft pulley can slip and the degree mark on the pulley can migrate.

Soooo, even though you line up the mark on the pulley with the crankcase, the crankshaft itself isn't lined up.
That's why you probe to make sure the hole is there.
And BTW, that's also a good sign to know you need to replace the crankshaft pulley/harmonic balancer/damper...if the TDC mark is off by more than a couple degrees the pulley is failing and could either continue to walk around or even migrate inwards and damage the crankcase or migrate outwards and fly off the crankshaft.

In the old days I would take a scribe or magic marker and mark a line radially on the harmonic balancer. When the line broke it was a sign the balancer needed to be replaced because the isolation layer had failed.

This is what happens/looks like a failed balancer: