Carb question

[Sully]

for starters..... I know nothing about carbs. Just basic stuff I've heard and read here and there.

basically.... I'm having issues with the carb I put on the RX-7. I bogs real bad if you hit the throttle quick but its fine if you ease into it then nail it. The accelerator pump isn't squirting like it used to. I read this in the edelbrock carb book.

Pump System: When the throttle is opened rapidly, the air flow through
the engine will increase immediately. The fuel, since it is much heavier than
the air, will “lag” behind. This contributes to a temporary lean A/F condition.
Regardless of cause, a solution is to temporarily enrichen the A/F Ratio
by mechanically pumping a small quantity of fuel into the throat of the
carburetor (Figure 7). The Edelbrock carburetor has a piston that draws fuel
into the pump cavity past the plunger lip-seal when the throttle is closing
(1). Upon opening, the lip-seal seats, allowing the plunger to force the fuel
through another one-way valve, the Pump Discharge Ball and Weight (2),
and the Pump Jets (3) into the primary throats.
The pump plunger is not driven directly by the throttle, but through an
intermediate Pump Drive Spring (4) that extends the duration of the “pump
shot” past the time the throttle stops moving. The Edelbrock Performer
Series carburetor has an external pump lever with three hole locations
for link attachment providing three distinct pump delivery curves. This is
further explained in “Calibrating The Pump”.

I really only understand the bold parts. The accelerator pump isn't squirting this small amount of fuel like it used to when I first put it on. What could cause that?

 

[glh_turbo22]

Strang, that carb never did that when it was on the stang. Make sure you check that the squirter is working while the engine is running. The float bowls could be low if your testing them while the engine is stopped.

 

[2004boss]

for starters..... I know nothing about carbs. Just basic stuff I've heard and read here and there.

basically.... I'm having issues with the carb I put on the RX-7. I bogs real bad if you hit the throttle quick but its fine if you ease into it then nail it. The accelerator pump isn't squirting like it used to. I read this in the edelbrock :thumbdn:carb book.



I really only understand the bold parts. The accelerator pump isn't squirting this small amount of fuel like it used to when I first put it on. What could cause that?

could be the problem the accel pump is probably bad or you got to much carb on it could be a number of things but if the accel pump isnt squirting my moneys on that. get yourself a Holley.

 

[Sully]

Strang, that carb never did that when it was on the stang. Make sure you check that the squirter is working while the engine is running. The float bowls could be low if your testing them while the engine is stopped.

Nah.. it was working great when we first put it on. I think the co-owner fucked up the gasket when he was setting float heights. He replaced the accelerator pump and it was still wrong. I replaced the gasket and it started working again. I always have to redo everything he does... lol. :icon_wink

It still has a stumble on off idle starts and on hard right turns. we went down 2 jet sizes and it seemed to help now I think we need to adjust the floats more. Which way? I have no idea. lol Its a learning process. I've never messed with carbs before so its pretty interesting.

We woulda got a Holley if one was available in our price range. Didn't want to spend alot on a LeMons.