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General Information => General => Topic started by: srgtlord on February 28, 2012, 10:57:11 pm
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I misread how to get the injection pump pulley off the car....I had the camshaft locked and the injection pump locked. So I went to crank the bolt off the injection pump and noticed the timing belt bowing upward between the camshaft and the injection pump about a quarter of an inch :o So in an act of desperation I managed to shim the cranshaft with the waterpump pulley tool to keep it from moving and was able to remove the injection pump nut...... So I guess my question is....did I bend any valves :'(
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I really doubt it.
I'm assuming you had it to TDC on cylinder 1, right? I would hope so, because it makes things easier to put back together if you know where it's supposed to be. Anyway, that means cylinders 1 and 4 are all closed, so if you push the piston up into them they are going to be seated and not likely to bend with the small amount of force you were placing on the crankshaft. The ones that are open are 2 and 3, but the pistons should have been at the bottom of those cylinders and it takes more than 1/4" to bring them up (a half turn to be specific). That's where the damage happens, when the belt breaks they are all the way open and have the full travel of the piston to smack them.
But in any case they're engine valves. If they couldn't take a little bit of force applied to them by turning the crank, I would seriously question their ability to hold in 22:1 compression and several thousand explosions per second. There's a huge difference between an engine spinning at 3000 RPM and your applying some torque to it. That spinning engine has some serious inertia and isn't coming to a stop easily.
Crank it over by hand a few times when it's all back together and if everything feels fine with no binding up it's probably OK.
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I'm going to highly doubt it, srgt.
The pistons would have been moving counter-clock, as in going back down from where they just came, not getting into any overlap, since you were trying to loosen the nut.
Add that to what Baja said.
Did you get the sprocket off ?
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The pistons would have been moving counter-clock, as in going back down from where they just came, not getting into any overlap, since you were trying to loosen the nut.
Yeah, that too, unless it sprung back but still... the stuff isn't made of glass.
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I had a flashback to changing a timing belt on a porsche 944 and bending the valves....stupid porsche.... But Thats good to know. I stopped last night when it was pitch black out. Im off to go pull the injection pump pulley off with a small puller
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It was probably just the slop in the belt. I usually just put the locking pin in the IP and loosen. If anything moves it should be relative to eachother and no harm. Pretty much sounds like that is what you had happen anyway.
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Well removed the camshaft pulley and the injection pump pulley, pulled the injection pump, found the timing belt tensioner nearly seized, and discovered a mixture of diesel and oil dripping out of it. Im guessing the leaking diesel did a number on the camshaft/ crankshaft/ intermediate seals.
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Just as a side note, I removed the camshaft pulley nut with the belt on , injection pump lockpin in and camshaft lock in place and....(drumroll please) nothing broke ;) I figured since I pulled a pulley of my spare junk engine with just the cam lock in place and nothing happened I could duplicate it again.
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Just as a side note, I removed the camshaft pulley nut with the belt on , injection pump lockpin in and camshaft lock in place and....(drumroll please) nothing broke ;) I figured since I pulled a pulley of my spare junk engine with just the cam lock in place and nothing happened I could duplicate it again.
Not the best technique. Although you got away with it, and may always get away with it, statistically, there are increasing numbers of those that don't .
Best to lock pulley with a 'Y' shaped lever.
The way I do it is with nothing locked, a sharp hit on a 19mm/3/4 " wrench. This pulls on the belt a bit but relies on the inertia of the cam and valve springs. Easy as pie...
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Yeah lots of times I don't lock the cam to loosen the bolt.
I use an impact wrench (I hit a wrench with a hammer).
Even a strap wrench can hold it for that but I usually try to loosen it before the old belt is removed.