lilgoomba
New member
Long story short, I have a freshly rebuilt 200 bottom, CI aluminum head and intake, 390 cfm Holley, and DUI ignition. I have yet to get this combo to idle at all, although it will run, poorly, at a higher rpms. As you let the rpms drop, it will sputter and die.
Things I've checked:
Ignition - I was getting a very poor spark from the DUI, so I sent it in and they said it had some kind of defect. They did fix it for free, but I'm still not totally confident that this dizzy is reliable.
Compression - I'm getting almost exactly 150 on all cylinders. Hopefully this means that the valvetrain is working right, but I could be wrong. This brings me to...
Valves - I set these according to the procedure in the shop manual. They seems to be opening and closing properly, and I don't hear any clatter.
Carb - This has been difficult to tune since I can't get the engine to idle. The float level seems good on both bowls, and the idle mixture screws are set out about 2+1/2 turns. It's fed by an electric pump.
Vacuum - Now this is where I think it has a big problem. I'm getting very poor vacuum when I hooked up a gauge to the carb base. I've sprayed carb cleaner around to test for leaks, but can't find any.
Other notes:
I don't know if it's because it's a new build, but this thing runs HOT! Within a matter of a coulple minutes, the electric fan kicks on and cools it off. It almost defies physics as how hot it gets and how fast. This makes me think that there's some kind of massive vacuum leak. THe water pumps seems to be working ok because the heater hoses and radiator hoses also get hot.
Sometimes it makes a squealing noise when it gets really hot like that, so I kill it immediatly. I'm going to try taking the belt off and run it cold for a short time to see if it's the belt or an accessory.
My technical level is shade tree, so hopefully someone out there can help me out with this. It's really starting to hold up the whole restoration.
Things I've checked:
Ignition - I was getting a very poor spark from the DUI, so I sent it in and they said it had some kind of defect. They did fix it for free, but I'm still not totally confident that this dizzy is reliable.
Compression - I'm getting almost exactly 150 on all cylinders. Hopefully this means that the valvetrain is working right, but I could be wrong. This brings me to...
Valves - I set these according to the procedure in the shop manual. They seems to be opening and closing properly, and I don't hear any clatter.
Carb - This has been difficult to tune since I can't get the engine to idle. The float level seems good on both bowls, and the idle mixture screws are set out about 2+1/2 turns. It's fed by an electric pump.
Vacuum - Now this is where I think it has a big problem. I'm getting very poor vacuum when I hooked up a gauge to the carb base. I've sprayed carb cleaner around to test for leaks, but can't find any.
Other notes:
I don't know if it's because it's a new build, but this thing runs HOT! Within a matter of a coulple minutes, the electric fan kicks on and cools it off. It almost defies physics as how hot it gets and how fast. This makes me think that there's some kind of massive vacuum leak. THe water pumps seems to be working ok because the heater hoses and radiator hoses also get hot.
Sometimes it makes a squealing noise when it gets really hot like that, so I kill it immediatly. I'm going to try taking the belt off and run it cold for a short time to see if it's the belt or an accessory.
My technical level is shade tree, so hopefully someone out there can help me out with this. It's really starting to hold up the whole restoration.