The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 1971 C-10 knocking sound and not reving past 3000 RPM

aruss99 · 04-30-2015, 12:23 AM

I have a 1971 C-10 pickup and have recently found that the truck will not rev over 3000 RPM and when it gets to around 2800 RPM, an popping sound is made from under the hood. The motor is a 350 SBC with an Edelbrock 1406 carb and Edelbrock intake. Also the distributor has no points on it. Not quite sure what that means. Other than that the motor is stock, that I know of. The tranny in the truck is a TH400 which seems to be working fine. I have read that there can be many things causing the problems I have described with the 3 major ones being timing, spark plug gap, and compression. Right now I have the timing set at 12 degrees, a plug gap of .042 and the compression was between 9.1 to 8.5. I am not sure if that is too big of a difference. Also it appears that my motor is running way rich which I plan to fix going down the road as I don't have lots of money to spend. Maybe that has something to do with it? I don't know. Any help would be much appreciated because I am 15 and this is the first vehicle I have had to work on like this. Thanks.

04-30-2015, 12:23 AM	#1
aruss99 Registered User Join Date: Feb 2015 Location: Phoenix Arizona Posts: 122	1971 C-10 knocking sound and not reving past 3000 RPM I have a 1971 C-10 pickup and have recently found that the truck will not rev over 3000 RPM and when it gets to around 2800 RPM, an popping sound is made from under the hood. The motor is a 350 SBC with an Edelbrock 1406 carb and Edelbrock intake. Also the distributor has no points on it. Not quite sure what that means. Other than that the motor is stock, that I know of. The tranny in the truck is a TH400 which seems to be working fine. I have read that there can be many things causing the problems I have described with the 3 major ones being timing, spark plug gap, and compression. Right now I have the timing set at 12 degrees, a plug gap of .042 and the compression was between 9.1 to 8.5. I am not sure if that is too big of a difference. Also it appears that my motor is running way rich which I plan to fix going down the road as I don't have lots of money to spend. Maybe that has something to do with it? I don't know. Any help would be much appreciated because I am 15 and this is the first vehicle I have had to work on like this. Thanks.