Camshaft pulley bolt loosening

[KeithG]

So, I did the timing belt, water pump, & engine seals this weekend on my 2000 Toyota Avalon (185K miles, 1MZ-FE engine.) To say that I’m happy with myself is an understatement. I took a couple of shortcuts to get at the oil seals. I want to ask the experienced folks here if my way of loosening the camshaft pulley bolts was foolish or not (i.e. did I risk damaging the engine?) I don’t see this technique in this site’s archives, but I think I read about it somewhere.

I posted a description on toyotanation that I’ll paste below:

Here's the trick on the camshaft bolts. After you get the old belt off, put it back on one of the pulleys. Wrap the belt completely around a pulley (as I just said), and get all of the teeth engaged. Now fold the "doubled belt" back around the same pulley. After wrapping that pulley, you'll have enough of the belt remaining to loop it over the idler pulley, or even the other camshaft pulley. Just get the rest of belt looped onto something solid. Then you can start turning the camshaft pulley bolt. The belt will loose its slack, and then it gets locked tight. You have to initially fold the belt in the correct direction for it to work correctly when loosening the bolt. You can fold the belt in the opposite direction when you need to tighten the bolt again later. This works better with an extra hand or two, but I did it fine all by myself.

BTW, the original water pump was in near perfect condition. It spun like butter, and I kind of hated to swap it out. I've been running old green coolant in this thing since I bought it in 2006 (@ 95K miles.) I should say, I've been running fresh ethylene glycol coolant in her.

 

[djb]

That sounds fine to me.

The usual technique is using a vise-grip pliers with the old belt, which puts about the same stress on the sprocket as your approach.

 

[tinmanSC]

Sounds like it would work just fine, and it seems that it did. When I did this job on my Nissan VG33E and 2x Toyota 2JZ-GE engines, I used a partner and strap wrench to hold the cam in place while I used the poor-mans impact wrench on it (a socket wrench and a hammer). Worked great. Using the old belt probably would have been better, because it had teeth sized to fit. They make a special tool for doing this called a cam holder, but I didn't have one at the time (I do now).

Doing this on an interference engine like the 1MZ-FE (after 1999) always gives me a heart attack. I'm so fearful of moving the cam when the crank isn't connected via a belt I did this really slowly.

Replacing the water pump is a good idea, even if it was working fine. You're already in there.

 

[KeithG]

You are right on about the heart attack sensation, tinman. I used a dab of paint to mark the pulleys so that I could easily see the pulley rotation. I didn't pull the plugs, so I always have a few 'pulley leaps' along the way.

Turning the key and hearing the sound of the engine running again, is such a rush.

 

[mechtech2]

That would work with no harm to the gear.
But, an interference engine could have problems, and remember, we have to retighten that bolt!
It is a good idea for special situations. Why not use the factory method, though? Normally the cam is held by a wrench, and the bolt loosened.

 

[tinmanSC]

Originally Posted By: KeithG
Turning the key and hearing the sound of the engine running again, is such a rush.

I know exactly what you mean! I video taped mine!

 

[KeithG]

Thanks for the thoughts. The same technique works to tighten the bolt too! You just need to wrap the pulley in the opposite direction.

Very good point about the interference aspect. Thank you again!!!

The factory method involves holding the cam-shaft with a wrench, right? (My book mentions that.) This requires removal of the valve covers, which was something I wanted to avoid. I was under the impression that getting the bank 1 valve cover off is rather involved, and also requires quite a bit of expense regarding new gaskets. Is that not the case?

It wouldn't surprise me if I'm off track with my line of thinking. Almost everything seems to me to be rather involved

 

[mattd]

cam pulley holders are inexpensive it is a good investment.

 

[cptbarkey]

used the vicegrip/old belt method recently too and also worked like a charm.