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Old 09-03-2008, 10:44 PM   #1
1969 k/10
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miss fire

So there is a list of problems that i think are related.
When i try and crank the engine the stater grids massively.
After much grinding i get it started and it sounds like a miss fire or the timing is wayyyy off.
I checked it with the light and i couldn't even see the mark. Could it be the far off?How could it have gotten this way? Also i'm pretty sure its making the starter grind with the engine turning the wrong way because of timing.

Any help appreciated. Thank you.

.
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Old 09-03-2008, 11:04 PM   #2
68gmsee
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Re: miss fire

A defective harmonic balancer can cause it to be off or the timing chain slipping. Sometimes a different balancer may be installed.

Here's the way I check mine:

I remove all the spark plugs to make the engine easy to turn. (If you don't do that, make sure you disconnect the battery cable for safety purposes.)

I remove the #1 spark plug put my finger in the hole and turn the engine with a wrench on the cranshaft bolt until I feel pressure. This means the piston is on it's compression cycle.

At this time I insert a long screw driver in the hole and keep turning the engine until the piston as the very top.

At this point the harmonic balancer should be at TDC with the mark and the distributor rotor should be pointing to #1 piston position.
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Old 09-04-2008, 12:31 AM   #3
1969 k/10
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Re: miss fire

ill try that
but im not sure how the timing would even get that far off it was the problem
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Old 09-04-2008, 06:02 AM   #4
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Re: miss fire

This might be a dumb question, but when you checked it out with a timing light did you plug the vaccum line going to the distributor? If not the added Vacuum advance will cause the timing mark to be way off.
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Old 09-04-2008, 07:38 PM   #5
PanelDeland
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Re: miss fire

Give some more info.From what I'm reading you may have timing issues or you may have timing issues.
Does the truck run at all?
How many miles on the engine?
Did this start suddenly or over time?
The reason I ask is that it may be timing but from the description it could also be a timing chain.
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Old 09-07-2008, 10:18 PM   #6
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Re: miss fire

So i got the timing back to normal but idk how it jumped that far advanced. Yes it did happen at once. The truck was running but it was also grinding the starter(relation?) Don't know about how many miles are on the engine, but it still seems to have a good amount of life left in it.
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