73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: the29bman@yahoo.com on August 17, 2017, 01:29:15 pm
-
I have a 1976 K20 with a 292 in it. I replaced the plugs, plug wires, distributer cap, rotor, ignition module, PCV valve and fuel filter. Initially the truck runs fine but as it gets up to operating temp it bogs down and has hardly an acceleration. I checked all the parts I installed replaced the vacuum lines rechecked the timing. Not sure were to troubleshoot next.
-
What carburetor do you have on it? Is the choke operating correctly?
Was the issue present before you did the tune up?
-
The truck seemed to be running ok beforehand. it is the rochester mv. I have only owned the truck for about 6 months and previous owner had rebuilt the carb
-
Make sure the fuel filter isn't installed backwards. Recheck the firing order, 1-5-3-6-2-4. Did you verify the spark plug gap before installing them? Did you change any carburetor settings?
-
Rechecked the firing order and ensured that the gap was correct. I did not change any carb settings. I have been thinking a vacuum or choke issue. I will post a picture tomorrow as I have a question on where the vacuum line to the vacuum advance goes into as I see two identical holes right next to each other on the valve cover side.
-
Did you verify that the fuel filter located behind the inlet nut of the carburetor is not installed backwards?
-
yes. The fuel filter was changed after this problem started.
-
I had also dropped the fuel tank to replace the float sensor. It is the two hose style I also replaced the rubber fuel lines and made sure there were no kinks o and that it was being smashed.
-
Did you replace the parts all at once or a few at a time, in steps? How far off was the timing?
-
Possible defective part or parts installed if everything checks out
-
Timing was correct the plugs, wires, cap, rotor and ignition module al changed at the same time. replaced the new coil and ignition module already.
-
I may be fighting the same issue currently. I too bogging down under load. Especially as it gets warmer. May want to advance timing a little if you can. My spec sheet called for 10* but I set it for about 13* and it seemed to help a lot. Some people here go as far as 16*. And how about the fuel pump. I just replaced that in my truck seeing if that was issue.