With Mech pump? Or do you have electric as well? If I dont start mine for 2-3 weeks (has only happened 1 time) it took some cranking and pedal pushing. Usually it fires right up, but I drive it 5x a week lately.
3/8 vs 5/16 fuel lines
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With Mech pump? Or do you have electric as well? If I dont start mine for 2-3 weeks (has only happened 1 time) it took some cranking and pedal pushing. Usually it fires right up, but I drive it 5x a week lately.
It was either add the pump or find the return line to the tank Maybe I'll try it without the mechanical fuel pump The electric is running all the time
Stock mechanical pump only. One car is a properly working thermostatic choke and other is mechanical. Choke, tap, key, run.
Another issue with running two pumps is one can give you X psi and then the second pump will raise x's pressure some more. Could the OP being popping his float needle valves and actually flooding the engine when it won't spool up?
Issue with cars that take a lot of cranking to get started off a mechanical pump... is sometimes the pump check valves are stuck open.... and the fuel drains back to the tank.
It goes thru a fuel line pressure regulator set between 4to6 pounds just before the carb. Thermoquads don't need much pressure
In my 69 Swinger 340 with a 408 w2 I chose to run both electric and mechanical . The electric only gets used for racing or to fill the lines after a long rest . And I used a 1/2" pickup in the tank and feeding into the Holley pump just outside it. My thinking is the pumps will have an easier time sucking up the fuel out of the tank .
I'm thinking if the throttle and secondaries are all working I'll start replacing the smaller fuel lines one section at a time till I get back to the gas tank. Maybe I'll see something else while I'm down there. I just don't understand why it's not popping like it's lean. Thanks all and Merry Christmas. Jim
OK. How
I don't know what rhetorical means Anyways how much more power did you feel after the secondaries were fixed
I was trying to be sarcastic I guess neither joke worked very well Anyways I hope it's the secondaries not opening.but I doubt it
Did you check to see if the butterflies were opening all the way.
Haha that is funny ! I wasn't sure how to define the meaning to you if you didn't already know .
I have to double check
Having never used one, does a thermoquad have mechanical secondaries or vacuum?
The quick answer is yes. lol It's a hybrid. The base plate is mechanical. When the throttle is moved to WOT, all four open. The carburetor top has a vacuum operated adjustable air door that regulates air flow through the secondary venturii.
@sorewrist1 what I would do regarding the fuel line would be to leave the 5/16 line in place, UNLESS you are planning on replacing it due to rust, kinks or some other physical reason. Then I would go ahead and make the upgrade to 3/8, since the lines are "about" the same price. 5/16 line will supply 500 plus HP. However, it certainly will hurt nothing to go to 3/8 if you are replacing it "anyway". That said, I don't think that's your issue.
If all else fails, I would look at the float level. There are "several" float settings for different applications depending on performance. I always set dead center of those specs. It could be that as hot as it sounds your engine is, the float level might need to be raised. It's really not a bad procedure to do. If you do "everything else" and still no luck, I think that is what it will be. I'll be more than happy to walk you through it on the phone, OR if you want to send it back after you determine that's what it is, I will raise the float level for you and reimburse you for shipping and ship it back. Just let me know when that time comes and I'll be glad to help however you want.
...and thank you for the kind words.
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Thanks Rusty I'm about 500 miles from
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