fuel leak from pump outlet

-
rich006

rich006

Learning as I go
Joined
Nov 21, 2013
Messages
549
Reaction score
129
Location
Annapolis, MD
I disconnected my fuel line at the pump outlet to conduct a fuel pressure test. It tested good (about 4 psi) but now that the line is reconnected there is a leak. I believe the problem is on the pump side of the fitting, not the flared tube end, because I have swapped the flared tube connector with the one that was at the carburetor inlet, and the leak stayed at the pump end. What can I do? I sure don't want to replace the pump again, as that was a real PITA last time.
 
Don't know. Is this a performance pump that comes apart? Does it have pipe thread outlet with an adapter to inverted flare, or is the tube fitting part of the pump?

And did you use a backup wrench on the fitting? Easy to crack/ break the fitting / casting etc etc.
 
Yup. You've managed to crack the pump where the line screws in. Not hard to do as it's only aluminum.
 
If the fitting has a hex shape, that says you need to support it with a wrench, 2 wrenches required to tighten or loosen.
 
Yep, I was using two wrenches. But I guess I must have overtightened it. I'll replace the pump.
IMG_3494.JPG
 
rich006 said:
Yep, I was using two wrenches. But I guess I must have overtightened it. I'll replace the pump.
View attachment 1715633493
Click to expand...
Recheck your pressure after replacing the pump. Check it at the carb. Much easier. I have found stock mechanical pumps put out 10-12# and that is way too much pressure for all carbs.
 
On my 67, removed the alternator. Fuel pump is easy enough. On my 73 with a/c, that alternator bracket was in the way as much as the alternator. Took it off also. I dont recall if I lost coolant at those bolts. Too long ago. My mind worked a lot better back then. I might have drained some coolant in forethought and real sealed those bolt threads. Anyway... Good luck with it
 
toolmanmike said:
Recheck your pressure after replacing the pump. Check it at the carb. Much easier. I have found stock mechanical pumps put out 10-12# and that is way too much pressure for all carbs.
Click to expand...

Actually this is a good example of a shortcut making the job harder. I've done the "slant six fuel line mod" where you run a hose from the pump to the filter, then another hose over the valve cover instead of the hard line going around the front of the engine (the mod is supposed to reduce fuel boiling in the carburetor when you park with the engine hot). With that mod, I have NPT/hose adapters at the pump and the carb. I originally was going to check pressure at the carb, but I didn't have a female NPT connector that I could use to connect my Harbor Freight vacuum/pressure gauge. I decided it was easier to undo the NPT fitting at the pump than to remove the hose from the carb fitting (those hoses are a pain to get off). And you know the rest of the story.
 
New pump solved the problem. It wasn't even that hard to replace. I never did see any cracks or other damage in the leaky pump.
 
RustyRatRod said:
Yup. You've managed to crack the pump where the line screws in. Not hard to do as it's only aluminum.
Click to expand...

Actually the part the line screws into is steel. What usually happens is someone trys to turn the fixed hex and it cracks the spot weld. Or, they try to loosen the line nut without holding the fixed hex with a wrench.
 
MoparMike1974 said:
Actually the part the line screws into is steel. What usually happens is someone trys to turn the fixed hex and it cracks the spot weld. Or, they try to loosen the line nut without holding the fixed hex with a wrench.
Click to expand...

Actually, it depends on which pump he has.
 
You must log in or register to reply here.
-

Back
Top