Formula78

Thanks for the input everyone! I guess I'm not throwing in a new accelerator pump .

I had both bowls off before installing it on the motor last year to check the floats. I got them adjusted properly and not seem to have problems with the fuel level in the bowls. But I will have to re-check this again by looking in the hole once it is on the motor again.

While I had the bowls off I verified that the correct gaskets were installed properly. I did not see any debris in the carb, it looked very clean inside. Also I did check to make sure the accelerator pump cam was not pre-loaded up on the pump.

I will begin by checking all the needles and jets and making certain that everything is flowing well when the throttle linkage is rotated. Is there anything else I should be checking when I get it apart? I have a good place to start thanks to all the great advice I got here! I'll keep everyone posted as to what happens!

formula31

Interestingly enough, on a twin application the stock squirter and pump work fine. Its only on a heavy single deep v that these particular carbs get in trouble, and ive had this happen with numerous 780's. Of course the intake, heads, cam, cam timing all play a part. I did have one that I picked up where somebody had cut the secondary spring in half and the secondary was trying to open off idle. Was a huge dog until I found that.

blkhorse

you said you ran that motor for 2 hours last year before the rod bearings went.if it ran good then,it either has debri or maybe it wasn't put back together right

Formula78

Ok guys, took it apart, Any ideas? here are some pics:

Formula78

more

Formula78

some more

Formula78

and the last ones

RumRunner

With that much soot on the bottom of the carburetor, and in the bores it appears to be running too rich. You may not have enough initial timing in the engine, or one of the air bleeds in the top of the carburetor may be gummed up. Spray out all of the orificies with a good carburetor, or brake cleaner before putting it back together.

Formula78

Hmm, I figured it would be Lean by the way it was running. I will be certain to make sure the timing is dead on next time it comes together. Nothing looked gummed uo when I took the carb apart, but I will throughly clean it with some good brake cleaner before I put it back together.

So maybe my problem is in the distributor? I will buy a re-curve kit to curve it back to stock because I dont know what has been done to it in the past. It WAS owned by rednecks before me.

coolcarwrench

I do a lot of jetting on hot rods and the same problem always happens with Holleys when you install larger heads and cam. I suggest you change your primary jets up 4 sizes, then work down from there, it is easier to tune that way. Almost always with Holleys you have to install bigger squirters on the acc. nozzles. I like to ones that have the small tubes for orifices. Then you need to buy the plastic acc. cam kit, which has different ramping to bring the squirt in sooner, you want the squirt to come in just as soon as you touch the throttle. Its all about getting the fuel in quickly.