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Discussion Starter · #1 ·
I swapped an engine in from a 76 to my 77 and there came a problem. I put on another head, but then it developed a problem, so I put the 76 head which was on the 76block. I didn't have anything marked so my valve timing with the chain was sketchy...at best. What is there that I can do to figure out the valve timing with the engine in the car?

A further problem is that the old crankshaft had an exposed notch like __/ \__ which fit on to the pulley-wheel. The 76 engine had a imposed notch like --\ /-- and I put the old pulley-wheel on it. I can't be sure if my timing marks are at all accurate b/c you know it takes a hella lot of force to get that pulley on to the crank, and it could have shifted. So, my idle is fine, but I have no power under-load. I've tried every timing position and so I've conlcuded my valve timing must not have been done properly by the guy whom I entrusted to do it...
Any ideas??/
 

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Problem is probably ignition timing, but....

Take out the number one sparkplug & roll the engine over till you get to top dead center compression (hold your thumb over the plug hole until you feel compression building and then match the timing mark on the crank pulley). Once you have the crank positioned you can secure the cam chain and then adjust the cam position (there should be a mark on the cam, behind the sprocket that you can allign). Then try the sprocket in the three different dowell positions and see which position allows the sprocket to fit into the chain with the least rotation of the cam. You should also get a service manual. By the way have you tried removing the distributor bolt and setting the timing? If the oil pump chain has been off you could have the oil pump shaft out of time which will put your distributor out of the adjustment range.
 

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Discussion Starter · #3 ·
<b>RE: Valve timing...</b>

From what you've said it sounds like valve timing. when I put my head back on from changeing the head gasket I got the timing a little off and it was a little hard start but idled fine and had no power, especially above 4k.

Jared
 

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Discussion Starter · #4 ·
<b>Thanks, Jared you answered my ?</b>

Thanks so much!! Jared. You seem to have answered my question I posted last week.I have just put in a crank in my 81 na and have no power at all above 4K just as you discribed.I have checked the timing it is right on!! Also when the motor is at TDC I can take off the oil cap and the cam lobs are pointed up in a V shape.What way does the cam need to turn?Also can you adjust the sprocket with the timing cover on?

Thanks again
Jason
 

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Discussion Starter · #5 ·
Thanks so much guys. I am just worried all that work on putting the engine back in got messed up. Is the fact that it starts, idles, revs, and will move itself postitive enough for me to think it is just a timing problem? I've gotten so discouraged with the car...many stories! She's a sweet car...
So, as far as valve timing goes...it is pretty impossible to have then off, right? I mean, if I move one link it is clear the valves are not perfectly V-d up at TDC. There is no such thing as "valve advance" is there...since this is a stock cam?
Thanks again...Dave
 
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