Urgent help needed - timing belt replacement.

[och]

So, I'm in the middle of a timing belt/water pump replacement, and I think I've messed up. I got to the point where I aligned the cam pulleys and crankshafter pulley, and removed the timing belt. And now it's time to remove the damn crankshaft pulley bolt, which I can't seem to get. But that's not the main problem, the problem is that while I've been trying to get it off, I turned the crank full 360 several times, and then I realized something - even if I align it with the 0 mark again, it may not necessary be aligned with cams, since it only aligns every other turn. How can I determine if the alignment is correct?

 

[och]

By the way, once I get to the water pump, how far am I from the headgasket? I'm doing the repair because my water pump was faulty, and I've been drivin for a while with overheating engine, and while I didn't blow the head gasket, I imagine it might have sustained some damage, and it's not a bad idea to have it replaced.

 

[och]

One more thing, while trying to get that damn bolt out, I've turned the crank counter clockwise a few times - is that really bad? I know Lexus recommends turning it clockwise only.

 

[rms]

How did you remove the timing belt before you removed the crank bolt and the harmonic balancer as well as the tensioner assy ?

Did you cut the timing belt ? Or have you only removed the serpentine auxiliary belt ?

 

[och]

How did you remove the timing belt before you removed the crank bolt and the harmonic balancer as well as the tensioner assy ?

Did you cut the timing belt ? Or have you only removed the serpentine auxiliary belt ?

I actually do not have it removed completely, its just removed from the cam pulleys - I followed the tutorial on lexls.com.

 

[Lextreme II]

http://www.lextreme.com/timing.htm
http://www.lextreme.com/timing2.html

 

[cribbj]

Just a few points of caution from one who's fought the timing belt monster recently:

1) Strongly suggest you go to a Lexus dealer and buy "only" the OEM timing belt, not one from NAPA or elsewhere, even if it's a Gates or other well known brand. For some reason, the aftermarket timing belts seem to be just a bit longer and can be difficult to tension.

2) When putting the belt on, one of the tricks that isn't stressed enough in the FSM (or why) is making sure when you install the belt, that all the "slack" is over where the tensioner is located. If this isn't done correctly, the three marks may look like they line up correctly on the pulleys, but it still may be slightly out of time. Sounds weird, but it can happen, especially with an aftermarket belt which is just a bit longer than it should be.

Lexus/Toyota did us a favor by putting the three marks on the timing belt, and they are definitely a big aid to getting the belt on quickly, but if you have an aftermarket belt that doesn't fit exactly right, those three marks can be right on the money, but the timing can still be off.

I currently have a Gates aftermarket belt on my 1UZ, and the only way we were able to keep it timed right, was to insert a 3/16" shim under the tensioner: http://www.lextreme.com/forums/showpost.php?p=77137&postcount=80

Also have a look at post 78 which shows the hazards of running a worn out, or too long timing belt. And post 74 is where I described the problem.

 

[och]

http://www.lextreme.com/timing.htm
http://www.lextreme.com/timing2.html

But there's nothing in these links that explains how to deal with my problem

 

[gloverman]

To crack the nut try removing the torque converter cover under the bellhousing and locking the ring gear with a pry bar. I recommend undoing the crank nut before removing the cambelt - hopefully you have an early non - interference engine - if yours is the later Post 96 from memory - then take the heads off now. The crank lines up every turn as two pistons come to TDC at a time. If you can't find the head gaskets I don't recommend doing the job - cheers

 

[cribbj]

If you mean your problem about having turned the crank several times without moving the cams, don't worry about it.

If you line up the notch on the timing belt drive pulley, with the dot on the oil pump housing, then you're fine, as long as the marks on the cam drive sprockets are lined up with the corresponding fixed marks on the brackets behind them.

Think about it, if #1 cylinder is at TDC, the piston/rod/crankshaft doesn't know if it's TDC on the compression stroke or exhaust stroke. It's the position of the valves that determine that. So as long as you keep the cam sprockets lined up on their marks, you can turn the crank 360 degrees, 720 degrees, etc. and it's OK. Just make sure when you're finished, that you line up that notch with the dot on the oil pump. See the photo below for what I'm talking about.

As far as turning the crank CCW, you haven't caused any damage as most engines are designed to run in either direction, depending on their camshafts. However when you go to mount the timing belt, be sure the crank has been rotated CW and so have the cams so that any mechanical "slop" in the system will be in the same direction. Try not to turn the valve train CCW, however, as the scissors gears and the rest of the components weren't designed for that direction of travel.

 

[striker]

You can make up an
"hold the crank pully steady while I give the lockbolt a big wallop with a hammer"
Tool
like I did,

Just get hold of a piece of realy hard wood, like 3" by 1" or more and about a meter long, drill a hole in the middle of the wood the size of the socket that's needed to go on the crank pulley bolt.

Now look at the front of the cranck pulley there's also 2 small holes, M8 bolts fit in those but you need quite long ones, on most older rusted pulley the thread is not really in shape anymore but even then this should still work. drill the holes in the wood so it all fits together.
put the piece of wood in front of the pulley, put in the 2 M8 bolts you can now hold the crank and keep it from turning. put the socket through the hole in the piece of wood and put the wrench on, take hammer and give it a whack, if if doesnt come loose whack a little harder, make sure the piece of wood is not in your hand but supported of somthing rigid, you need to scare the bolt loose. if you can get it in the space an air powered impact wrench does wonders.

toyota use a similair tool as a "special service tool" and I made one out of steel, this one also fits 4age engines btw.

ps if the engine's out of the car you can put an 8mm bbolt through the flexplate and lock it like that.

Grtz thomas (el cheapo backyard engineering again, sorry for that)