Can't find TDC; need help
#1
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Car: '89 Chevrolet Camaro IROC-Z
Engine: L98
Transmission: TH-700R4
Axle/Gears: B&W 2.77 Posi
Can't find TDC; need help
I heard that balancers can slip over time, plus this is a rebuilt engine, so I think that I ought to find the "real" TDC instead of trusting the factory mark.
I'm going to [try to] do this with the engine still in the car and with the heads and timing cover all still on the engine. I just bought a new timing wheel and an adjustable piston stop bolt, and the only literature that I have between the two are the instructions printed on the wheel (not very helpful) and these instructions .
I understand what I'm ultimately trying to do, but what I don't get is how the heck that I'm supposed to turn the crank if the engine is still in the car and the timing wheel is where the crank pulley was. Both instructions say to somehow "rotate the crank" but, with the engine still in the car, I don't really have anything to grab on to.
Could someone tell me how I'm supposed to do this?
Thanks!
I'm going to [try to] do this with the engine still in the car and with the heads and timing cover all still on the engine. I just bought a new timing wheel and an adjustable piston stop bolt, and the only literature that I have between the two are the instructions printed on the wheel (not very helpful) and these instructions .
I understand what I'm ultimately trying to do, but what I don't get is how the heck that I'm supposed to turn the crank if the engine is still in the car and the timing wheel is where the crank pulley was. Both instructions say to somehow "rotate the crank" but, with the engine still in the car, I don't really have anything to grab on to.
Could someone tell me how I'm supposed to do this?
Thanks!
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Car: 85 Monte Carlo SS...
Engine: T.P.I L98.
Transmission: TH350
Axle/Gears: 3:73 Posi
Pull out all your spark plugs and the crank will move with ease. I beleive it is a 13/16 bolt, so a 1/2 drive ratchet with the socket mentioned and fix er up. The hole ede mentioned will work great too.
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Car: '89 Chevrolet Camaro IROC-Z
Engine: L98
Transmission: TH-700R4
Axle/Gears: B&W 2.77 Posi
Mabye I'm not picturing this correctly but, how would cutting a hole help you get a socket on the crank?
BTW -- I'm trying to actually *mark* my balancer, so I need to leave the balancer on the crank when I do this. That means that the timing wheel is going to go on the balancer, not directly onto the crank snout.
BTW -- I'm trying to actually *mark* my balancer, so I need to leave the balancer on the crank when I do this. That means that the timing wheel is going to go on the balancer, not directly onto the crank snout.
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Car: 85 Monte Carlo SS...
Engine: T.P.I L98.
Transmission: TH350
Axle/Gears: 3:73 Posi
Ahh. Doesn't you balancer have a keyway??? It should. THe balancer is only suppose to go on in one spot????? It shouldn't slip.
#6
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Car: '89 Chevrolet Camaro IROC-Z
Engine: L98
Transmission: TH-700R4
Axle/Gears: B&W 2.77 Posi
Mabye I'm not picturing this correctly but, how would cutting a hole help you get a socket on the crank?
BTW -- I'm trying to actually *mark* my balancer, so I need to leave the balancer on the crank when I do this. That means that the timing wheel is going to go on the balancer, not directly onto the crank snout.
BTW -- I'm trying to actually *mark* my balancer, so I need to leave the balancer on the crank when I do this. That means that the timing wheel is going to go on the balancer, not directly onto the crank snout.
#7
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Car: '89 Chevrolet Camaro IROC-Z
Engine: L98
Transmission: TH-700R4
Axle/Gears: B&W 2.77 Posi
Okay, I don't know why the heck my computer posted that message again... sorry 'bout that!
Cruzin: The crank has a key on it, and the balancer has a slot that corresponds with it, if that's what you mean. I know that can't really slip. But I've heard that the outer "ring" of the balancer can slip relative to the rest of the balancer, and that's what I'm trying to "fix".
(On a side not, I don't really see how that can happen, but I've heard of it happening many times before... plus my balancer is 160K miles old...)
Anyway, regarding your first reply... are you suggesting that if I remove all of my plugs that the crank ought to move easily enough to move with my hand (i.e. by the balancer)?
Cruzin: The crank has a key on it, and the balancer has a slot that corresponds with it, if that's what you mean. I know that can't really slip. But I've heard that the outer "ring" of the balancer can slip relative to the rest of the balancer, and that's what I'm trying to "fix".
(On a side not, I don't really see how that can happen, but I've heard of it happening many times before... plus my balancer is 160K miles old...)
Anyway, regarding your first reply... are you suggesting that if I remove all of my plugs that the crank ought to move easily enough to move with my hand (i.e. by the balancer)?
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Car: 85 Monte Carlo SS...
Engine: T.P.I L98.
Transmission: TH350
Axle/Gears: 3:73 Posi
Originally posted by sancho
Mabye I'm not picturing this correctly but, how would cutting a hole help you get a socket on the crank?
BTW -- I'm trying to actually *mark* my balancer, so I need to leave the balancer on the crank when I do this. That means that the timing wheel is going to go on the balancer, not directly onto the crank snout.
Mabye I'm not picturing this correctly but, how would cutting a hole help you get a socket on the crank?
BTW -- I'm trying to actually *mark* my balancer, so I need to leave the balancer on the crank when I do this. That means that the timing wheel is going to go on the balancer, not directly onto the crank snout.
Again you balancer should not move. They are suppose to have a notch in it for a keyway. If it is spinning then you should get it double keywayed then. Or replace it.
#9
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Car: '89 Chevrolet Camaro IROC-Z
Engine: L98
Transmission: TH-700R4
Axle/Gears: B&W 2.77 Posi
Yeah, it was a double post, and now we're playing tag. I'll stop posting for a while...
#10
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Car: 1987 Camaro Z-28
Engine: 6.3L Victor EFI
Transmission: Tremec TKO 600
Axle/Gears: Moser 9"/4.11 Trac-Lok
I did mine by drilling three 1/2" holes in my degree wheel that corresponds to the three holes for the crank pulley. Then bolted the wheel on by the center bolt, snugly enough to hold it in place, after lining up the outer three holes. Next I threaded three 3" bolts into the balancer & used a breaker bar to turn the engine with these bolts. You need to then mount a piece of coat hanger wire or welding rod to act as a pointer.
#11
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If you trying just to find TDC, it works best with two people. First, you can remove all of the spark plugs, that makes the engine easy to turn over. Put your index finder in the #1 spark plug hole, covering it completely. Have a friend crank the engine untill you feel pressure on you finger, and the pressure pops off your finger.
Screw in the piston stop, put it far enough in so when you rotate the engine again, it wont just go through the power stroke. Beg, borrow, or steal a flywheel wrench. Have someone go under and rotate the engine(the correct way). If the piston doesn't hit the stop, it isn't in far enough. Back up and screw it in some more. Do this until you get the piston to hit the stop, and when you loosen the stop, its continues without intteruption, and when you tighten it, it won't go any more.
When you got the piston exactly at TDC, look at you timing pointer. It SHOULD be lined up with the mark already on you balancer. Your just checking, right? If it doesn't line up, then I'd just replace the balancer, instead of just trying to mark an old, worn out balancer that will just move off mark later down the road.
Burnout
Screw in the piston stop, put it far enough in so when you rotate the engine again, it wont just go through the power stroke. Beg, borrow, or steal a flywheel wrench. Have someone go under and rotate the engine(the correct way). If the piston doesn't hit the stop, it isn't in far enough. Back up and screw it in some more. Do this until you get the piston to hit the stop, and when you loosen the stop, its continues without intteruption, and when you tighten it, it won't go any more.
When you got the piston exactly at TDC, look at you timing pointer. It SHOULD be lined up with the mark already on you balancer. Your just checking, right? If it doesn't line up, then I'd just replace the balancer, instead of just trying to mark an old, worn out balancer that will just move off mark later down the road.
Burnout
#12
Powerhouse Products makes an excellent engine rotating tool, it screws into the harmonic balancer and then you put a ratchet or break bar in the 1/2 inch socket in the front. Its about $28 bucks.
Not the greatest solution for this one time use but I thought I would throw the idea out there.
http://www.powerhouseproducts.com/st...Code=POW103090
Not the greatest solution for this one time use but I thought I would throw the idea out there.
http://www.powerhouseproducts.com/st...Code=POW103090
#13
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Ballancers do move... Even though
the ballancer is comprised of an inner hub and an elastic middle and an outer ring.. They do in fact Move when they inner mass rotates and the Elastic Band center looses grip... The only kind that Does not Move is a Fluid Damper Type/ Centrifugual Weighted design..
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