Barabbas Posted April 3, 2013 Report Posted April 3, 2013 A couple of weeks ago my fuel pump started pumping a lot of fuel out the vent hole. So after searching around for a new fuel and pump and not finding an exact replacement, I ordered a power wagon fuel pump from Vintage power wagon. It went into "Doris" ,my P23 with no problems, I did have to do a little replumbing but that was all. Took it out for a test drive --car started fine but would lose power every time I took a left hand corner. Got back in the garage and discoved that the rear carb was leaking fuel around the base. I thighted the mounting bolts down which seemed to fix the problem. The old Plym ran find for about 50 miles, includind a 70mph run on I-69. Last night as I pulled into the garage it died. Started her up this mornging, she idle rough and died. I restarted, this time with the fast idle engaged--she ran well but GAS started flowing out of the front Carb. It appears that gas is leaking from the main vent tube. It's not a problem at low speed but a few seconds of higher rpm and the gas starts to flow out. The carbs are B&B that I bought from George Asche about 4 years and 7000 miles ago--had no problems with either of them until now. Is this just really bad timing with my fuel system or am I missing something basic? Another piece of miscellaneous data-- last summer I moved from the Pac NW to the midwest so the past few months were the first cold , low humidity weather that Doris has seen since she got the new carbs Quote
Don Coatney Posted April 3, 2013 Report Posted April 3, 2013 You might check your fuel pump pressure. That may be why your carbs are leaking. Where did you move to? Indiana? Quote
Barabbas Posted April 3, 2013 Author Report Posted April 3, 2013 Don, I'm in Fort Wayne now--back amoung friends and family --I lived here from the mid 80s to 2007. I moved out to the Olympic Penisula when I retired, to be near the mountains and ocean, I discovered that "there's no place like home". How do I test for fuel pump pressure, is there a special gage for fuel pumps? The only pressure gages I have the hand held type for compression testing, I'm afraid if I used that gage I'll get a lot of leadfree octane in my eye. Quote
Barabbas Posted April 3, 2013 Author Report Posted April 3, 2013 I should add that I'm not positvie that my leak is at the main vent tube, it's hard to see exactly where the gas is coming from. It could be from the throttle shaft or maybe a gasket. The leak is in the front of the carb and below the reservoir Quote
Don Coatney Posted April 3, 2013 Report Posted April 3, 2013 My vacuum gauge is a compound gauge and can be used to test fuel pump pressure. Where in Fort Wayne? I grew up there and have a son who lives there. Quote
mrwrstory Posted April 3, 2013 Report Posted April 3, 2013 (edited) New fuel pump and not a stock replacement may be the initiator of the problem. As others have indicated, perhaps too much pressure. And then ,...hope the extra pressure did not do damage to tired parts downstream from the pump. Edited April 3, 2013 by mrwrstory Quote
Barabbas Posted April 3, 2013 Author Report Posted April 3, 2013 My vacuum gauge is a compound gauge and can be used to test fuel pump pressure. Where in Fort Wayne? I grew up there and have a son who lives there. Don, right now I live on the SW side--Aboite area but in my previous 25 years here, I lived NE, southwood park and wildwood park-so I know the town pretty well. Give me a message next time your visiting your son and we can meet at Mad Anthony's, have a beer and swap bloody knuckle stories Quote
Barabbas Posted April 3, 2013 Author Report Posted April 3, 2013 Continuing saga---I've been playing around, tightening stuff etc. The float is set pretty low about .110" so I don't think that's the cause. The more I test it appears that the leak now happens after I shut off the engine. I think it is coming from the throttle shaft area. Could this be caused by a stuck needle valve? One other thought I've had is that the output tube of the new fuel pump sits closer to the the exhaust manifold than my old pump, and my car does not have a hear shield--could I have the dreaded boiling gas issue even though it's 40F out? Quote
Barabbas Posted April 3, 2013 Author Report Posted April 3, 2013 New toy on order (fuel pressure/vacuum(sp) guage)--I'll report back in a couple days when I have some readings Quote
Barabbas Posted April 7, 2013 Author Report Posted April 7, 2013 Got a pressure guage---Fuel pump output is 4.5 psi, surprised me, I was convinced the new pump was the problem. Fooled around today with float height but still can't stop her from flooding the front carb (back carb is operating fine). The float is boyant but I want to pull it out and give it the shake test..is there a trick to taking the float out without removing the needle valve/seat? Quote
Dodgeb4ya Posted April 7, 2013 Report Posted April 7, 2013 Did you check for debris in the needle and seat on the front carb? High fuel level caused by a leaking needle and seat could be sloshing over on turns and flooding throttle plate and shaft at shut down too. Bob Quote
Barabbas Posted April 7, 2013 Author Report Posted April 7, 2013 Bob, I haven't yet but that will be the next step. I was just in the garage fueling around and noticed that when I shut car off, gas kept dripping into the venturi like an old TBI system. After a few minutes I took off the carb top and the fuel level in the bowl was very low, so one of my jets may also be gummed up Quote
Dodgeb4ya Posted April 7, 2013 Report Posted April 7, 2013 Parts of your old fuel pump diaphram could have ended up in the needle and seat causing your troubles! Bob Quote
Barabbas Posted April 7, 2013 Author Report Posted April 7, 2013 Well, she's working although I really can't say why. I took the needle valve and seat out, they looked cleanbut I wiped them off and blew on them for good measure. I noticed that there were several ( about 20) small black specs in the carb bowl. ( The specs were like flakes of carbon micoscopic thin and probably only .005-.010" square). So I cleaned out all the gas and sediment, reset the float, put her back together. Took her for a 10 mile test drive with a lot of left hand turns and several stop, turn off, restart cycles--she started find, no flooding,no surging, no loss of power. It always makes me nervous when I "solve" a problem without really knowing what I fixed. So I'll keep my fingers crossed for the next couple of days Quote
Dodgeb4ya Posted April 7, 2013 Report Posted April 7, 2013 That was easy! Kinda sounds like rubber particulates? Quote
Young Ed Posted April 8, 2013 Report Posted April 8, 2013 I would say even though you didn't see it there was something in that needle/seat. Quote
Barabbas Posted April 8, 2013 Author Report Posted April 8, 2013 Yep it did turnout to be easy and probably was crap in the needle valve--but I'll take another 10 mile drive tomorrow before I'm totally relieved. Bob, they might be small rubber particles--I'll tear down the old pump next week and see if there is any detiorating black rubber in there, or maybe the short section ( 6" or so) of rubber gas line connecting from my fuel rail to my carbs Thanks to all for their advice Quote
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