timing belt slips off tensioner B230 engine
#1
timing belt slips off tensioner B230 engine
Hi Everybody,
1987 740 turbo, B230FT engine.
I've changed a few timing belts in my time, but this is a first.
After changing all front oil seals, I put a new tensioner (INA) on and slipped on and aligned new timing belt to the pulley wheels. Once I released the pin to let the tensioner take up slack, I rotated the crankshaft 1 whole revolution (CW) and the belt was starting to slip off the tensioner roller. If I go 2 revolutions of the crankshaft, the timing belt is barely hanging on the roller. Yes, the hanging pin of the tensioner is pushed into the background hole in the front of the engine.
I had torqued overhead camshaft bolt to 37 ft-lbs but had not yet torqued intermediate camshaft to that spec. Is not torquing intermediate camshaft bolt to that spec part of the problem because it's not properly aligned with the overhead camshaft?
Any ideas? Thanks.
1987 740 turbo, B230FT engine.
I've changed a few timing belts in my time, but this is a first.
After changing all front oil seals, I put a new tensioner (INA) on and slipped on and aligned new timing belt to the pulley wheels. Once I released the pin to let the tensioner take up slack, I rotated the crankshaft 1 whole revolution (CW) and the belt was starting to slip off the tensioner roller. If I go 2 revolutions of the crankshaft, the timing belt is barely hanging on the roller. Yes, the hanging pin of the tensioner is pushed into the background hole in the front of the engine.
I had torqued overhead camshaft bolt to 37 ft-lbs but had not yet torqued intermediate camshaft to that spec. Is not torquing intermediate camshaft bolt to that spec part of the problem because it's not properly aligned with the overhead camshaft?
Any ideas? Thanks.
#2
RE: timing belt slips off tensioner B230 engine
Make sure the harmonic balancer/crank pulley are lined up properly, they're keyed but I've seen the pin get smashed and whatnot. Also make sure those stay plates are in place on your crank pulley for the timing belt.
My timing belt slipped off when my harmonic balancer flew off while driving. It was a mess.
My timing belt slipped off when my harmonic balancer flew off while driving. It was a mess.
#3
#5
RE: timing belt slips off tensioner B230 engine
Thanks, guys. Yes, I have the back crankshaft shim (which doesn't lock to crankshaft); pulley boss (or gear), which is keyed to the crankshaft; front crankshaft shim, which is keyed to the pulley boss; and the crankshaft gear/harmonic balancer, which is keyed to the pulley boss.
I suppose I had better doublecheck that there is no burr or something like that on the crankshaft that is hanging up the front shim. Still, the alignment of the intermediate camshaft over the crankshaft looks dead on.
But, I will check.
I suppose I had better doublecheck that there is no burr or something like that on the crankshaft that is hanging up the front shim. Still, the alignment of the intermediate camshaft over the crankshaft looks dead on.
But, I will check.
#7
#8
RE: timing belt slips off tensioner B230 engine
Tech, nope. They're put on correctly. I labeled overhead with an "O" and intermediate with an "i," respectively, when I took them off.I also did remember to put the washer behind the overhead cam gear. There was no washer for the intermediate.
#9
RE: timing belt slips off tensioner B230 engine
OK are you sure the washer was behind the cam gear?
Some had them but alot didn't have the washers. But the washer would fit unless it is supossed to be there it would have to have the hole to slide over the pin to fit. If you look from the side of the car does any of the pulleys look out of line?
Some had them but alot didn't have the washers. But the washer would fit unless it is supossed to be there it would have to have the hole to slide over the pin to fit. If you look from the side of the car does any of the pulleys look out of line?
#10
RE: timing belt slips off tensioner B230 engine
The washer has a slot to fit over the cam key. Yes, it was behind the gear because I took photos almost every step of the way. What I did discover, looking back at some of the photos, was that the cylindrical hole (on left) of the tensioner guide rod was out a bit rather than being pushed all the way in over the protruding guide post on front of engine. Maybe I just have to adjust this so as to tilt the roller.
#12
RE: timing belt slips off tensioner B230 engine
Tech, update.
1) pulled crankshaft pulley, shims, and pulley boss and made sure everything was pushed up tight on crankshaft.
2) torqued crankshaft bolt to 100 ft-lbs. Better, but belt still slips.
3) Seems that overhead camshaft pulley could be pushed forward 1/8 - 1/4", since the belt slips off about that much after several revolutions of the crankshaft. Strange. There was no problem with the old belt and tensioner roller for the current overhead camshaft. The original keyed washer is in back of the overhead camshaft pulley-its original position.
4) May put in old tensioner roller tomorrow and see if that helps.
This is really strange! Am I missing something?
Thanks.
1) pulled crankshaft pulley, shims, and pulley boss and made sure everything was pushed up tight on crankshaft.
2) torqued crankshaft bolt to 100 ft-lbs. Better, but belt still slips.
3) Seems that overhead camshaft pulley could be pushed forward 1/8 - 1/4", since the belt slips off about that much after several revolutions of the crankshaft. Strange. There was no problem with the old belt and tensioner roller for the current overhead camshaft. The original keyed washer is in back of the overhead camshaft pulley-its original position.
4) May put in old tensioner roller tomorrow and see if that helps.
This is really strange! Am I missing something?
Thanks.
#16
RE: timing belt slips off tensioner B230 engine
Tech,
Removed the 2-mm washer; didn't help. The belt still slips off.
I may have to put another washer in there, or perhaps the cam gears are old and the teeth are rounded.
Also, I'm using a Conti-tech belt. I heard they have a good reputation.
What do you think? Should I get new cam gears?
Removed the 2-mm washer; didn't help. The belt still slips off.
I may have to put another washer in there, or perhaps the cam gears are old and the teeth are rounded.
Also, I'm using a Conti-tech belt. I heard they have a good reputation.
What do you think? Should I get new cam gears?
#17
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