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Old 10-23-2020, 03:56 AM   #1
tino0217
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No power all of a sudden

My 71 C10 350 sb, after finding a short from an after market tach installed for timing purposes led to changing my hei distributor, coil and module also found my radiator was shot so I replaced it. I went through the timing like I did before, 3 yrs ago, 12° advanced and it ran like a champ. While I was trying to figure out why I wasn't getting any power I found there was a intake leak so I replaced the gasket. Now with everything done hoping to fix any gitty-up set backs, I find myself back at square one. The engine sounds a lot more powerful with good compression better than it ever did but I can't get any power when I give it gas. I'm getting some slight backfiring in the exhaust and was able to take that down by adjusting the carb air-gas mixture. The only thing that I need to look at, as of now, is my automatic choke because it doesn't seem to be working the way it did after everything I've done. Could this be part of the problem? Any suggestions would be appreciated.
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Old 10-23-2020, 06:44 AM   #2
68bbc/20
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Re: No power all of a sudden

i'd check tdc for #1 cylinder again, sounds like it was 180degrees off.
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Old 10-23-2020, 09:29 AM   #3
geezer#99
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Re: No power all of a sudden

Quote:
Originally Posted by 68bbc/20 View Post
i'd check tdc for #1 cylinder again, sounds like it was 180degrees off.
You do know it can’t run if it’s 180 degrees off!
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Old 10-23-2020, 09:30 AM   #4
geezer#99
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Re: No power all of a sudden

Quote:
Originally Posted by tino0217 View Post
My 71 C10 350 sb, after finding a short from an after market tach installed for timing purposes led to changing my hei distributor, coil and module also found my radiator was shot so I replaced it. I went through the timing like I did before, 3 yrs ago, 12° advanced and it ran like a champ. While I was trying to figure out why I wasn't getting any power I found there was a intake leak so I replaced the gasket. Now with everything done hoping to fix any gitty-up set backs, I find myself back at square one. The engine sounds a lot more powerful with good compression better than it ever did but I can't get any power when I give it gas. I'm getting some slight backfiring in the exhaust and was able to take that down by adjusting the carb air-gas mixture. The only thing that I need to look at, as of now, is my automatic choke because it doesn't seem to be working the way it did after everything I've done. Could this be part of the problem? Any suggestions would be appreciated.

Post some pics of your choke and all around your carb.
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Old 10-23-2020, 10:43 AM   #5
truckster
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Re: No power all of a sudden

Are you sure you got the plug wires in the same positions? If they're off, it could still run but would be very advanced or retarded, depending on which direction they're off.
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Old 10-23-2020, 11:48 AM   #6
68bbc/20
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Re: No power all of a sudden

If its wired for 180 degrees off, number 1 back on number 6 position it will run and not have any power! Ive pulled the distributor and got every thing back corrected on a couple different truck before.
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Old 10-23-2020, 01:46 PM   #7
HO455
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Re: No power all of a sudden

Double check that the plug wires are properly installed. I think I it is 5 and 7 that can be swapped and the engine will run ok but it will be low on power. The PO of my Burban had two wires swapped when I bought it.
And as Geezer asked, please post some pictures so we can better help.
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Old 10-23-2020, 06:43 PM   #8
Lee H
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Re: No power all of a sudden

Distributor, GM, aftermarket? Did you check to see if the weights were free? What is your timing with vacuum at idle and about 1,500 rpms? Are you using ported or manifold vacuum?
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Old 10-25-2020, 08:50 AM   #9
Corts60
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Re: No power all of a sudden

popping through the exhaust = too advanced timing / rich
popping through the intake = too retarded timing / lean

As everyone mentioned, triple check your distributor was dropped in correctly.
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