The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - '69 C10 327 SBC Off Idle Stumble / Misfire Help

**HO455** · 10-30-2018, 11:04 AM

A couple of items that may help. It sounds like backing the timing off helped. Have you verified that your timing marks for TDC are correct?

Misfires while turning does suggest a float level problem. When you check the float level make sure that the floats are not fuel soaked or if brass that they have no fuel inside of them. Also check that they move freely when holding the air horn level and at angles to mimic the forces felt when turning.

Your plug wires could have high internal resistance that may be changing as you move the wires. Here is what I use to test plug wires and spark power.
https://www.amazon.com/Lisle-20700-C.../dp/B00IXMA1RY

Have you tried wiring the choke open to take it out of the equation?

It is quite possible that you have more than one problem contributing to your symptoms.

Here's a link to a valve adjustment procedure.

https://www.crankshaftcoalition.com/...raulic_lifters

10-30-2018, 11:04 AM	#45
HO455 Post Whore Join Date: Feb 2016 Location: Portland Oregon Posts: 10,804	Re: '69 C10 327 SBC Off Idle Stumble / Misfire Help - I feel like I've tried EVERYTHI A couple of items that may help. It sounds like backing the timing off helped. Have you verified that your timing marks for TDC are correct? Misfires while turning does suggest a float level problem. When you check the float level make sure that the floats are not fuel soaked or if brass that they have no fuel inside of them. Also check that they move freely when holding the air horn level and at angles to mimic the forces felt when turning. Your plug wires could have high internal resistance that may be changing as you move the wires. Here is what I use to test plug wires and spark power. https://www.amazon.com/Lisle-20700-C.../dp/B00IXMA1RY Have you tried wiring the choke open to take it out of the equation? It is quite possible that you have more than one problem contributing to your symptoms. Here's a link to a valve adjustment procedure. https://www.crankshaftcoalition.com/...raulic_lifters __________________ Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. RIP Bob Parks. 1967 Burban the WMB,1991 S(stink)-10 Blazer,1969 GTO, 1970 Javelin, 1952 F2 Ford 4X4, 29 Model A, 72 Firebird. 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377