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-   -   Fuel Pump? (https://www.yenko.net/forum/showthread.php?t=116284)

PxTx 01-01-2012 08:40 PM

Re: Fuel Pump?
 
Well, the return line comment is more for when you go electric. The fuel staving problem is probably your effort to prevent those green fragments from getting into your fuel pump.

I would not have any filter between the fuel tank and your pump- be it electric or mechanical. A pump typically does much better at pushing. A filter before it is a restriction. Your air bubble in the filter before the pump is trapped air. The filter will not fill up until tha air can purge out. That air bubble is also a restriction.

When the time comes for the electric fuel pump, I would encourage you to run a lare, 1/2" aluminum line as the main feed. You can use the old 3/8th as the return line from a nice regulator. The important part is that the new line has a good pickup so it doesn't suck air. The pump is designed to push, and will have a flame arrestor screen that will be adequte to keep any debris large enought odamadge the pump out. Put a filter on the push side of the pump to protect your carb. I know there are two schools of thought on where to place the filter, but I beleive they do more harm that good when placed before a pump.

TDW 01-01-2012 11:24 PM

Re: Fuel Pump?
 
I've never seen one of the glass filters be "full" of fuel. Be it in a car or on a motorcycle, they always look like they are half full. Maybe you are chasing a problem that doesn't exist? Like someone else said, I would pull the bowls and see if there is any trash in the needle and seat.

Mayhem 01-02-2012 12:40 AM

Re: Fuel Pump?
 
The glass filter is almost always full or above 75% anyway. The extra filter before the pump was to rule out anything coming from the tank.

So far, nothing has been found actually coming through the line. The green crap was found while the tank was off and the fuel strained.

We have concluded this must have come from the tank of the gas station where I gassed up when all this started.

I am going to replace the glass filter with the new plastic one, between the pump and carb.

Paul, your info on the 1/2" line for an electric is useful and will be put to use when I can order the setup I want.

This car is somewhere around 450 HP right now, and I just don't think a stock mechanical pump is adequate.
I know they have high flow mechanicals, but I honestly prefer the consistent volume of the electric, and the control of the regulator to maintain the suggested psi the carb wants.

Heading out to change the filters around as stated, and then change the oil. The needle/seat advise has been ruled out as it would run great for 15-20 minutes before faltering.

It is definitely a fuel delivery issue in the line. Hopefully, as Paul said, removing the extra filter will help. It ran great last night on a test run. Thanks.

Mayhem 01-02-2012 05:57 AM

Re: Fuel Pump?
 
Paul- (PXTX)

or anyone who cares to jump in as well,

there is only the 3/8" port on the fuel tank. When I add an electric pump, will it be 3/8" hose to the pump, and then 1/2" coming out of it, or can I replace the sending unit with one with a 1/2" line?

It would be nice to run braided line or hard line, but it seems there is going to be at least a very short hose jumper from the tank to the pump.

Is there another way? I know on my Camaro it was all braided line, but it was coming from a fuel cell, not a stock tank.

69 Post Sedan 01-02-2012 03:10 PM

Re: Fuel Pump?
 
I personally see no reason to change from a mechanical fuel pump to electric on a 450HP motor as long as you are running a good pump.

My motor, for example, is around 450HP and I shift at 7000 RPM's with no issues and I am running a edelbrock mechanical pump with a 3/8" fuel line.

Kurt [img]<<GRAEMLIN_URL>>/beers.gif[/img]

PxTx 01-02-2012 04:17 PM

Re: Fuel Pump?
 
Kurt, great example. I was in the same camp as you. How do you know you wouldn't benefit from an improved fuel system?

I gained .4 in the 1/4 with no other changes on a 350 hp set-up I would have sworn was sound.

69 Post Sedan 01-02-2012 04:40 PM

Re: Fuel Pump?
 
WOW.....that's significant. Maybe I should hook up the Holley fuel pump that's still bolted to the car just for sh!ts and giggles.

Thanks for the heads up Paul.

Kurt [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img]

Mayhem 01-02-2012 11:47 PM

Re: Fuel Pump?
 
Finally! All is well again.

I am only running a clear plastic fuel filter-no glass. The new fuel pump is running 10 lbs at idle, which is too high, but will have to ride until payday when I can start working on the electric pump conversion and get a regulator on it.

I also remounted my &quot;Cool-Can&quot; in a better spot and have all new fuel line. As well as an oil change and radiator flush with new coolant.

It's a happy car again, and I am very thankful this chapter is over with. Simple problems that become a 2 1/2 day nightmare.

Thanks for the help guys. I will be quiet (until I start the electric conversion). [img]<<GRAEMLIN_URL>>/whistle.gif[/img]


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