My truck is running like crap. It will dirve okay but when you let off the gas it won't idle. I've tried adjusting the idle and it just keeps dying. I put a new power valve and a new accelerator pump and my timing is set at 10 degrees. It has a duraspark distributor thats used and a accel super coil and an MSD box Its a Holley carb on a holley street dominator intake. I got it running okay and I put a vacuum gauge on the carb and it had plenti vacuum. any body have any idea what it could be.
Holley's are notorious for blown powervalves, causing vacuum- fuel leaks.. Did it EVER backfire?? Could be an internal vacuum leak. Try another carb?? Spray wd-40 arount the carb-manifold,when the idle speeds up..could be a clue..
I'll do that Wd-40 trick. I just changed the powervalve and it hasn't backfired and I checked it yesterday. Thanks
If it's a SBC, you may try more inital advance.. like 12 * The wd-40 or an unlit propane torch will give a lot of clues, as to where the leak is(if it is a leak) I had a Holley that would not idle, someone had changed the fuel blocks from diffrent carbs, with the wrong gaskets,and created a vacuum leak.. Clean and blow out with air the needle idle circuts,and idle air bleeds real good.
I had one that had porrosity in the main body, drove us crazy for a while. A really good idea would be; if you have access to a carb you know is good, try it, if even just for a few minutes, just to narrow it down, because, you know, it could be something else.
I'd have to say fuel problem. Plugged Idle circuit, low float level or bad vacuum leak. When you say that the timing is set to 10deg, did you set it there with the vacuum advance unhooked. I only ask cuz' a friend chased a similar problem of poor idle quality for a week and then I came over and we put a timing light on it and when I unhooked the vacuum line to the distributer he asked why, so I explained why and retimed it and it ran just fine. I think I had to turn the distributer almost a 1/8 turn to bring the timing back where it belonged. Good Luck
I did time it with the advance unplugged. This carburetor used to make the truck run great. Its a SBF I'm fixing to go out there and try the suggested WD-40 if that don't work I'm going to pull the carb back of and see what i can find. Thanks I'll keep ya'll posted on what I find
alright its fixed after lots of head scratching and testing I figured it out. I sprayed WD-40 on my rear vacuum log thing and It was leaking so I fixed that still no worky so I pulled the carb apart and remember I had jetted it up to a .68 from a .66 I changed the jets back and Its been running good again ever since. Thanks for all the help.
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