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Discussion Starter #1
I think I put my camshaft sprocket on wrong (skipped a tooth) when I bungled a head repair (gimme a break guys, it's my first attempt at a rebuild, still learning...). It idles a bit rough, almost wants to backfire when accelerating hard from idle, and it flunked a pre-smog test (machine said probable cause was timing is off).

How do I tell if my camshaft timing is off? I have a timing light and know how to set the distributor timing using the notch on the crankshaft pulley, but that won't tell me if my camshaft is off will it? All it'll tell me is that my distributor is sending spark at the right time based on the crankshaft, right?

And if I skipped a tooth when putting the chain on the cam sprocket, how do I determine which way I need to move the chain (i.e., move the sprocket one link to the left, or one link to the right...)?

Any advice would be appreciated.

-Rob
 

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Discussion Starter #2
I guess reading the earlier post about the shortcut you took it's comming back to bite as I thought it would (see reply if you want). You should take the front timing cover off and set the timing chain in properly like you should have done instead of trying a shortcut which wouldn't work anyway. Once you loose the tension on the timing chain it drops off the crankshaft gear and it would be way to lucky to get it put back on right by just pulling it back up. You got some work ahead of you. Bummer...
You just might be able to get around it with a adjustable cam gear but that would be in the hope it works area too and would just be more guesswork that would take lots of time and money.
It might be a good time to get a new timing chain and tensioner if you have a few miles on the car, you have to go through all the work anyway to get at it so replace it if it's getting on in years, take advantage of a bad situation.
 

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Discussion Starter #3
> I guess reading the earlier post about the
> shortcut you took it's comming back to bite
> as I thought it would (see reply if you
> want). You should take the front timing
> cover off and set the timing chain in
> properly like you should have done instead
> of trying a shortcut which wouldn't work
> anyway. Once you loose the tension on the
> timing chain it drops off the crankshaft
> gear and it would be way to lucky to get it
> put back on right by just pulling it back
> up. You got some work ahead of you.
> Bummer...
> You just might be able to get around it with
> a adjustable cam gear but that would be in
> the hope it works area too and would just be
> more guesswork that would take lots of time
> and money.
> It might be a good time to get a new timing
> chain and tensioner if you have a few miles
> on the car, you have to go through all the
> work anyway to get at it so replace it if
> it's getting on in years, take advantage of
> a bad situation.
Well I'm afraid that your looking at what BW is saying and going [email protected]#%#$$%#! but I think that's the way to go in order to be absolutely sure your cam is in phase with the crank, if you had a TDC stop (goes in #1 spark plug hole) and a dial indicator and degree wheel all set up you could determin which way your cam needs to go. But you would be spending more time and money to get this set up than if you remove the front cover and go with factory markings.
As to the timing light and ign. timing, Right, that is only showing the spark time in relation to the crank,not the cams' relation to the crank.
Next time (if there is one)
make a wedge first and put a couple of cheat marks on the chain and cam sprocket so that you will know it's all lined up properly during reassembly.
Hindsight is the clearest....

Jeff
 

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Do you have ANY manual?
most of them shows pictures of the factory marks to put your cam where it is supposed to be.
I cand send you at least the one with the marks on the back of the camshaft sproket and the small mark on the plate that retains the cam.

After you put your engine in TDC and choose between one of the 3 holes available in the cam sproket (it depends on the condition of the chain, new:1 worn:3)
the cam sproket v notch has to be just to the side of the plate mark (right or left...forgot but it is in the manual, I can get it if you dont have it)

Are you completely sure the tensioner entered the base as it is supposed to be?
if not, remove the cover, fi it's ok, you were just lucky

hope this helps,

CarlosZXT

> I think I put my camshaft sprocket on wrong
> (skipped a tooth) when I bungled a head
> repair (gimme a break guys, it's my first
> attempt at a rebuild, still learning...). It
> idles a bit rough, almost wants to backfire
> when accelerating hard from idle, and it
> flunked a pre-smog test (machine said
> probable cause was timing is off).

> How do I tell if my camshaft timing is off?
> I have a timing light and know how to set
> the distributor timing using the notch on
> the crankshaft pulley, but that won't tell
> me if my camshaft is off will it? All it'll
> tell me is that my distributor is sending
> spark at the right time based on the
> crankshaft, right?

> And if I skipped a tooth when putting the
> chain on the cam sprocket, how do I
> determine which way I need to move the chain
> (i.e., move the sprocket one link to the
> left, or one link to the right...)?

> Any advice would be appreciated.

> -Rob
 

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Discussion Starter #5
Can't get cover off...

You should take the front timing
> cover off and set the timing chain in
> properly like you should have done instead
> of trying a shortcut which wouldn't work
> anyway.

I tried like **** to get my timing cover off, removed all components in the way (including the radiator), but I wasn't able to loosen the crankshaft pulley nut. I worked it over with an impact wrench, but the dang thing's seized on there somehow. I'd decided to undo my wrong and redo it right, but there was nothing I could do to get that nut off. It just wouldn't budge.

That's why I ended up resorting to the prybar. And I'm kind of stuck now because taking off the cover isn't an option, unless I take it to a repair shop, where they'll charge me more than my budget allows.

Thanks for the advice though.
 

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Discussion Starter #6
Thanks, but can't get cover off

> Do you have ANY manual?
> most of them shows pictures of the factory
> marks to put your cam where it is supposed
> to be.
> I cand send you at least the one with the
> marks on the back of the camshaft sproket
> and the small mark on the plate that retains
> the cam.

> After you put your engine in TDC and choose
> between one of the 3 holes available in the
> cam sproket (it depends on the condition of
> the chain, new:1 worn:3)
> the cam sproket v notch has to be just to
> the side of the plate mark (right or
> left...forgot but it is in the manual, I can
> get it if you dont have it)

> Are you completely sure the tensioner
> entered the base as it is supposed to be?
> if not, remove the cover, fi it's ok, you
> were just lucky

> hope this helps,

> CarlosZXT

Thanks Carlos for the advice. I couldn't figure out what the 3 holes were for, and this cleared it up.

I can't get my crankshaft pulley off (tried everything including an impact wrench), so taking the cover off isn't an option in my budget....
 

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Re: Can't get cover off...

> You should take the front timing

> I tried like **** to get my timing cover
> off, removed all components in the way
> (including the radiator), but I wasn't able
> to loosen the crankshaft pulley nut. I
> worked it over with an impact wrench, but
> the dang thing's seized on there somehow.

That crankshaft pulley bolt is only 108 ft-lb. What impact wrench were you using? Electric or pneumatic? Which pneumatic?

Doug Dawson
[email protected]
 

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Discussion Starter #8
The 3 holes might be the key

> That crankshaft pulley bolt is only 108
> ft-lb. What impact wrench were you using?
> Electric or pneumatic? Which pneumatic?

> Doug Dawson
> [email protected]

Doug,

I think Carlos' post might be the key. I should've written it down, but I think that when I removed the cam sprocket, the post was on one of the other two holes, not the center. But when I put it back on, I put the post on the center hole.

Since I can't remember which hole it was in when I removed it, I can just remove it again and place it on the other two holes, and the one that runs best will probably be the right one. I'll use the dang wedge this time though!

I was careful to keep the chain relatively snug on the crank sprocket, so I don't think it's jumped a tooth there. I just used a coat hanger and had a buddy help me keep it snug as I removed the head (and again when I reinstalled the head after repairing it).

By the way, just a side note. I repaired my damaged head with J-B Weld epoxy. It had two studs snapped off (frontmost and rearmost exhause manifold studs), and a former owner tried to drill out the front stud with a hand-held drill. He missed, and chewed up the gasket-mating face of the head with his drill bit. Corrosion set in, and there was no way I could get the badly leaking manifold to seal against the head. That's what lead me off on this frustrating (but educational) adventure in the first place: had to remove the head to repair its snapped studs and deteriorated mating face. I used the J-B Weld almost like it was Bondo, then sanded it down flat. Drilled out the snapped studs on a drill press, re-tapped them, and they held fine. At least I've had one success in this saga.

-Rob
 

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Discussion Starter #9
Re: Can't get cover off...

> That crankshaft pulley bolt is only 108
> ft-lb. What impact wrench were you using?
> Electric or pneumatic? Which pneumatic?

> Doug Dawson
> [email protected]

If you have socket and 1/2 breaker bar that fits the flywheel damper nut, put it on there and wire the breaker bar to a solid component at the 90 degree angle and hit your starter a couple of shots. Worked for me with a 88 Olds.

Ray H.
 
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