I'm trying to fire up the Mav this morning and just moments after the engine starts up, it chokes out, even with my foot on the gas! I recently replaced the fuel pump, so I would be suprised if it has gone bad already. What else could be causing this? The Holley carb has an electric choke hooked up. I could unhook that and try again. Any ideas?
How long in a moment?? The reason I ask because it could be electrical problem instead of fuel related. I had a starter relay go bad and my engine would start and run and about 2 miles later the engine would die...sometimes it would die as soon as I got my hand off the key. After your engine dies..remove the air cleaner and look inside the carb while operating the throttle linkage and see if you see gas. I had a new fuel pump go south that was less than a week old.
It dies after about five or ten seconds. I adjusted the carburator screw thingies. That sort of helped. Its running okay now. I think I need to do some carb tuning. The car wants to lose power for a second when you hit the gas. It idles fine, and runs fast well, but it doesnt want to make the change from slow idle to high speed. Hmmm.
sounds like your carb adjustmenst are really out of wack. i find useing a vacume gage and a tach to set the idle air fuel mixture is best. put the vac gage on a manifold vac port. first set the idle speed to desired idle rpm. usually around 800 rpm. now you will want to adjust the idle mixture screws trying to achive the highest vac reading possible. i sugest turning each screw a max of one turn then swith to the other screw so they stay in a basic balance. you will want to do this when the engine is at operating temp. once you get that dialed in. the motor will not want to start up when its cold unless your choke is properly adjusted. i have no sugestions on tuning a choke, i alway just kinda mess with it till it seems to start easly for me and not be reviing to high.
I don't have a tach unfortunately. But I'm pretty sure the engine idles fast. Where is the idle speed adjustment in relation to the mixture screws? Last time I measured I was getting about 9.5 MPG which seems really thirsty for a 302.
Wow!! You should be closer to 20 mpg. Sounds like you need to rebuild your carburetor and adjust your timing. The Mixture screws are located at the bottom of the carb, behind the Limiter Caps...the fast idle screw is on the side behind the Choke Tube.
? accellerator pump daiphram could have a pin sized hole in it ? This is a very common problem. Very cheap to replace. Just put it back together the same way you take it appart.
you can get a tune up tach for around 30 bucks from most auto parts stores. it hooks up to the coil and a ground. its easy to use sence it will be under the hood with you when your tuneing on the car. these tachs also have dewell meter in them so if you have points still you can check those.
I have a Holley 4-barrel carb, and the engine is built up a bit by the previous owner. So I expect a little less fuel economy than normal, it definitely has plenty of power, which I love. I think It's definitely time to rebuild the carb. I see Holley makes kits called "Fast" and "renew". Naturally, I don't see any mention of my carb model in their literature. It has 34R 12380B cast on the carb. Is that the model #? I can't find any other identifying marks except that it has Holley cast in it all over the place.
Summit has kits and it should have instructions, most kits do. You should still be able to get almost 20 mpg. My 289 gets 19.5 if I act my age driving and it's pushing 390-400 hp with 3.25:1 gear 25" tires. The worst mileage I get is around 14 if I drive like I stolen it.
Wow, thats great! I wonder where my gas is going?! It's not leaking out that I can tell. It must be running super rich!
Try here: http://www.holley.com/data/Products/Technical/199R10219-3.pdf These are the instruction for your carb - the kits are listed separatly and should be available in renew kit and Trick kit. Renew Kit Carburetor Rebuild Kit 37-935 Renew Kit Carburetor Rebuild Kit Carburetor PN[0-80670/08-0770/0-90670/0-90770]
Thanks! I found an awesome manifold leak, and I noticed that the power brake and distributor ports on the carb were both hooked to the manifold! Doesn't that seem weird? I plugged everything up and it already runs much smoother. I was able to tighten down the mixture screws a few turns each and I bet I save some gas now.
