Fuel Supply (pump ?) problem
Thread Starter
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Joined: Dec 2009
Posts: 94
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From: Macomb Michigan
Fuel Supply (pump ?) problem
Hi all
I am working on my 75' and can't get any fuel out of the line. Cleaned the tank and the supply line to the pump. I could siphon fuel out of that line with a hand pump. However the original pump didn't pump anything. I put then a new pump in making sure that the pushrod sits on the lever of the new pump. Still, when I crank the engine I get nothing.
What could be the problem at this point ?
Thanks in advance for any input.
I am working on my 75' and can't get any fuel out of the line. Cleaned the tank and the supply line to the pump. I could siphon fuel out of that line with a hand pump. However the original pump didn't pump anything. I put then a new pump in making sure that the pushrod sits on the lever of the new pump. Still, when I crank the engine I get nothing.
What could be the problem at this point ?
Thanks in advance for any input.
Thread Starter
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Joined: Dec 2009
Posts: 94
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From: Macomb Michigan
Noonie, I disconnected the line from the carb and put an old plastic container at the end, so I know for sure nothing is coming out.
Any other thoughts ?
Thanks again.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
If you are not getting a perfect seal between the hose and the pump, you will not get gasoline to flow. Your hand pump probably has a different fitting than the pump, so being able to get fuel with the hand pump may not prove anything. It's another one of those "ask me how I know" things.
If you happen to be a courageous or maybe foolish person, you could put a hose from the fuel pump into a gasoline can and see if it pumps from there. But, it could be hazardous so do that at your own risk.
If you happen to be a courageous or maybe foolish person, you could put a hose from the fuel pump into a gasoline can and see if it pumps from there. But, it could be hazardous so do that at your own risk.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
You should really be able to start a suction action on the supply line at the front frame and just let it run into a bucket very, very freely.
Test your pushrod to see if it moves up and down with the engine cranking.
You can either have a worn pushrod, worn cam lobe or a bad pump.
First 2 aren't common at all.
Test your pushrod to see if it moves up and down with the engine cranking.
You can either have a worn pushrod, worn cam lobe or a bad pump.
First 2 aren't common at all.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Amazing how much crap can come out between filter changes.
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Le Mans Master
Joined: Apr 2001
Posts: 5,941
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From: Was New Orleans but swam to Baton Rouge LA
Cruise-In IX Veteran
When you changed the pump did the main feed line free flow? There is no restiction in that line and it should gravity flow to the pump. If you do not get any flow out of that line I would look for a restriction as mentioned in the rubber lines by the tank and then follow the main steel line looking for a kink.
Drifting
Joined: Dec 2002
Posts: 1,946
Likes: 28
From: Long Beach CA
It's rare, but sometimes the pump will not pump any gas, or pump only a very little, at cranking speed. If the engine is all together and ready to run, which I assume it is, pour gas into the carburetor bowl through the vent tube. That will run the engine for a minute or two. Put the fuel line from the pump into your bucket, and start the engine. That will show you if the pump is actually moving any fuel. As always, have someone standing by with a fire extinquisher.
Thread Starter
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Joined: Dec 2009
Posts: 94
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From: Macomb Michigan
Sigforty, you are right.
I siphoned the line again and now it is gravity flowing out of that line.
I cranked the engine a couple times and it pumped it out a little. Then the battery died.
The fuel looks really dark yellow though and I wonder if I should drop the tank and clean it instead of trying to pump all the particles out.
I siphoned the line again and now it is gravity flowing out of that line.
I cranked the engine a couple times and it pumped it out a little. Then the battery died.
The fuel looks really dark yellow though and I wonder if I should drop the tank and clean it instead of trying to pump all the particles out.
Le Mans Master
Joined: Apr 2001
Posts: 5,941
Likes: 281
From: Was New Orleans but swam to Baton Rouge LA
Cruise-In IX Veteran
Sigforty, you are right.
I siphoned the line again and now it is gravity flowing out of that line.
I cranked the engine a couple times and it pumped it out a little. Then the battery died.
The fuel looks really dark yellow though and I wonder if I should drop the tank and clean it instead of trying to pump all the particles out.
I siphoned the line again and now it is gravity flowing out of that line.
I cranked the engine a couple times and it pumped it out a little. Then the battery died.
The fuel looks really dark yellow though and I wonder if I should drop the tank and clean it instead of trying to pump all the particles out.
Safety Car
Joined: Oct 2005
Posts: 3,570
Likes: 1
From: Algonac Michigan
Did you check for a inline filter between the tank and pump. They were used quite a bit in the 70's and 80's. I imagine you did if you cleaned the line. If you don't have one it sounds like your sock may be pluged.
Never mind if you now get a free flow from the line before the pump.
It's begining to sound like a bad pump.
I don't know if you tank should be vented or not but I know a few guys here have had a issue in that respect also. Does it flow the same with the gas cap on as on as well as off?
Could be a worn rod or lobe on the cam but I agree with noonie that it would be rare.
Never mind if you now get a free flow from the line before the pump.
It's begining to sound like a bad pump.
I don't know if you tank should be vented or not but I know a few guys here have had a issue in that respect also. Does it flow the same with the gas cap on as on as well as off?
Could be a worn rod or lobe on the cam but I agree with noonie that it would be rare.
