Lots of gas = no gas?

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Vinnie

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Hey folks,

Lately when I put the pedal down a bit more than neccesary the engine rpm drops and slowly picks up. It feels like a temp. loss of fuel, can’t think of anything else.

My fuel filter looks like this, on a slight angle containing air:

cc2965512d820d89dcc69255a269debc.jpg


Is this a problem that needs fixing or could there be something else wrong? The engine idles fine and also runs fine at faster speeds. Revving using the throttle lever on the carb (car in park) works fine, it only seems to do this in drive...

Thoughts?

V.

 
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c9zx

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It maybe a long shot but, I'd check to see that the accelerator pump is functioning properly. Chuck

 

Vinnie

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I’ll read that tuning guide, thanks!

If the acc pump doesn’t work I’d notice that when revving in park too, no?

No comments on the fuel filter containing air and being on an angle?

 
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c9zx

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I’ll read that tuning guide, thanks!

If the acc pump doesn’t work I’d notice that when revving in park too, no?

No comments on the fuel filter containing air and being on an angle?
There is no load on the engine when the vehicle is parked. It will respond more rapidly to throttle position changes even if the accelerator pump circuit is not working properly. I'm not saying that is certainly the problem, I said it was a long shot based on what you posted. I hope you find and fix the problem without a lot of effort. Chuck

 

digithead

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This sounds like a carb problem more then fuel delivery. Ive never seen a case where angle of filter mattered. The fuel pump will do its job and push right thru that.

If in doubt, you could get a gauge and measure fuel pump pressure to rule that out, but I dont think it would give you that hesitation symptom. Any good carb guys around who know how to clean and tune them properly? Sounds lean at low end and when you step on gas and add more air it leans further before picking up

 
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Vinnie

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I'll check for squirting when operating the throttle and also see if I have a vac meter and use that to set idle (I'm not up for further tinkering with the carb myself at the moment).

More later this week (when I can get to my car again).

Thanks!

 

Vinnie

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Well, hooked up the vac meter to the intake and let the engine warm up. Choke was 100% open. Adjusted idle mixture screws from lean torich untill there was no more increase in vac.

I lost track of it running richer or leaner than before but the drop in rpm was gone. Wonder if it’s due to my changes or be ause maybe the other time the engine was colder...

Oh well, it ran pretty good and I had fun :)

Also I felt the thermostat opening coz suddenly the cold air became warm air. But that’s a bit off-topic now ;-)

 
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