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JDP
05-20-2010, 05:18 PM
I could not get the cheap Avanti to run on gas from the tank and assumed a plugged line, but found they were brand new. The guy paid about $300 to buy and install a electric pump a few years back, but it was not pumping. I took it apart and the rubber diaphragm had turned into something like sticky, black chewing gum from years of exposure to modern fuel.. I installed a new pump and now have the worlds ugliest driver Avanti.

Laemmle
05-20-2010, 05:30 PM
That is why you have to utilize SunOco Race fuel:-)

unimogjohn
05-20-2010, 05:37 PM
JDP, when do we get to see pictures? Remember beauty is in the eye of the beholder. I am sure that folks say my Avanti is ugly, but to me she is a beauty.

mbstude
05-20-2010, 06:08 PM
Speaking of pumps... I've tried 3 different pumps on my '58 Commander this evening. All 3 work great "on the bench". Bolt them to the engine and nothing. I was even able to get them to pump fuel from the tank by hand. Bolt back up to the engine and again, nothing. When I get back from the national meet I'll put an electric pump on it.

Or maybe I'll just strap a tank to the roof and gravity feed fuel into the carb.

Anybody want a '58? This one's very reasonably priced.

JDP
05-20-2010, 06:31 PM
JDP, when do we get to see pictures? Remember beauty is in the eye of the beholder. I am sure that folks say my Avanti is ugly, but to me she is a beauty.


I'll post some once I'm sure it's no longer a bio hazard.

lschuc
05-20-2010, 09:41 PM
I'll post some once I'm sure it's no longer a bio hazard.

Bio hazard Avanti? Those are probably the best kind!! :-)

studegary
05-21-2010, 03:39 PM
I could not get the cheap Avanti to run on gas from the tank and assumed a plugged line, but found they were brand new. The guy paid about $300 to buy and install a electric pump a few years back, but it was not pumping. I took it apart and the rubber diaphragm had turned into something like sticky, black chewing gum from years of exposure to modern fuel.. I installed a new pump and now have the worlds ugliest driver Avanti.

I do not believe that this had anythig to do with the new fuels. New fuel goes bad in about three months as opposed to three years.

In the mid-1960s, I worked for a rubber company where one of its products was fuel pump diaphrams for Ford. One of the tests that I ran was fuel pumps with current gas vs. fuel pumps with stale gas. The diaphrams in the fuel pumps with stale gas turned to yuck/mush in short order.

jnormanh
05-21-2010, 05:56 PM
I do not believe that this had anythig to do with the new fuels. New fuel goes bad in about three months as opposed to three years.

In the mid-1960s, I worked for a rubber company where one of its products was fuel pump diaphrams for Ford. One of the tests that I ran was fuel pumps with current gas vs. fuel pumps with stale gas. The diaphrams in the fuel pumps with stale gas turned to yuck/mush in short order.

Ummm, Gary, could you please explain your reasoning, I can't follow it.

"I do not believe this has anything to do with new fuels"

"New fuel goes bad in about three months as opposed to three years."

"The diaphrams in the fuel pumps with stale gas turned to yuck/mush in short order."

So, new fuel goes stale more quickly, And stale fuel rots diaphragms, but there's no link to new fuels?

You're making the few marbles left in my head rattle.

curt
05-21-2010, 06:39 PM
I think diaphragms have always turned to mush on stale gas is Studegary's point. The alcohol in the gas will make mush out of the older diaphragms ,not made, for today's gas. It does not need to be stale gas, to 'mush-a-fy' if it's a diaphragm made out of older materials. That is my opinion and experience.

studeclunker
05-21-2010, 07:37 PM
Hey Matt, you mean something like this?

http://i16.photobucket.com/albums/b18/Studeclunker/Daytona%20Twin/Bobs%20Daytona/BobsDaytona001.jpg

I had that boat tank in the spare tire well for a while. The gas tank to this car has a hole in it. Anyway, it made filling up really simple, just disconnect the quick-connect and set the tank right by the pump. When full drop it back into the spare tire well and re-connect. LOL, I'm quite sure there is a law against it, but what the heck? It worked.;):p

studegary
05-22-2010, 01:26 PM
I think diaphragms have always turned to mush on stale gas is Studegary's point. The alcohol in the gas will make mush out of the older diaphragms ,not made, for today's gas. It does not need to be stale gas, to 'mush-a-fy' if it's a diaphragm made out of older materials. That is my opinion and experience.

Yes, you got my point. Sorry if I was not clear to all.
My main point is that the diaphrams go bad with stale old gas as well as stale new gas. Old material diaphrams also fail due to the new gas, but for different reasons than the fuel being stale.

PackardV8
05-22-2010, 01:29 PM
Seems to be a random phenomenon. I've got a couple of genuine '50s-60s Stude production line units which are still running after many years of 10% ethanol unleaded. They often will sit for two-three years with gasoline in the tank, fire up and drive away with no problems.

thnx, jack vines

tomhoo
05-22-2010, 01:50 PM
Speaking of pumps... I've tried 3 different pumps on my '58 Commander this evening. All 3 work great "on the bench". Bolt them to the engine and nothing. I was even able to get them to pump fuel from the tank by hand. Bolt back up to the engine and again, nothing. When I get back from the national meet I'll put an electric pump on it.

Or maybe I'll just strap a tank to the roof and gravity feed fuel into the carb.

Anybody want a '58? This one's very reasonably priced.

Any possibility your fuel line rubbed a hole where it goes over the rear axle? If there is a small air leak there, the new/dry pump will not be able to prime itself. Sometimes you can have a car with that particular leak run fine for a long time because so much fuel sits in the system in front of that leak and since the leak is at the high point of the suction side of the system, it never drops fuel to the ground. The only real operational symptom could be fuel starvation going up a hill or when running through some gears at full power.

I've had no problems with fuel pump diaphragms ever and my car sits sometimes for over a year between startups. (Boy, I'm asking for it now, knock on wood.)

55s
05-22-2010, 04:30 PM
There are many persons that are using "un-ethanolled" super gas for this reason.

You should see the black crud that used to be gas after a few months in the tractor or snowblower gas tanks.

It is best just to take the old gas to the hazmat dump and use fresh.