2stroke1971

Fb, 12A....

Its had a fuel delivery problem off and on since we've owned it....getting progressively worse Id say. My son drove it for a year every day and only 3 times or so it died out on him...splashing gas down the throat would make it fire, sometimes would only run until that went away...sometimes it would just go.

since I took it over about 6 months ago its happened twice more...once on my son (who was driving it because his honda broke down) Not that I drive it much....once or twice a month until I get some things squared away.

I thought it was a vacuum situation on the tank since right before it did on my son this last time I had just plugged off the lines that used to go the the charcoal can, not realizing that the vent for the tank was there...and my son described a hissing from the gas cap that day.

I dropped the tank, it was pristine inside..the pickup was new looking...put new lines under there, I bypassed the vent valve in case it was faulty...basically my tank now vents through the line that used to go to the charcoal can under the hood. (always vented now)

Fast forward to tonight. On a whim, my wife and I took the RX out for a short errand. 3 miles in, it sputtered out. Cranked and cranked...nothing. I walked the two blocks more to the store, bought the soda we went out for and a can of carb cleaner. Came back, sprayed the carb full of carb cleaner and it started, but only until the cleaner ran out I guess. Some time later we tried again and it started and I was able to make it about a mile.

Sprayed it full of cleaner again, ran until that ran out.... 10 minutes later, sprayed it again, started it again and made it 2 miles home....(burning rubber the whole way)......

I checked the gas cap, no hiss of course....

I have read conflicting threads...is there a fuel pump relay on an 85 FB or not? I am going to hot wire the pump to a toggle at least as a troubleshooting measure for now.

Not worried about flooding...I mean what does it do if you are at a stop light for 6 minutes? pump is running, you are not using much fuel...it has a return line, etc....

Any comments or suggestions would be appreciated!

Cookboy

iTrader: (10)

You're seeing fuel in the bowls thru the sight glass, or no?

DriveFast7

iTrader: (1)

Rebuild the carb and install a fuel pressure gauge near the carb.

2stroke1971

Carb is rebuilt.....no gauge though. I will check into that.

As for the sight glasses....Id have to get a dental mirror and a light or something

Actually I do have an inspection mirror...I should carry it with me in case this happens again.

I am basing my diagnosis solely on the fact that even when it will not start...it will run all I want if I hit it with some ether or carb cleaner.

I believe the pump on it is an afermarket unit, but I dont know which kind...doesnt fit in the recess like a stock one should.....

Thanks for the replies!

Jeff20B

iTrader: (13)

Time for another fuel pump, then? Sounds like it works when it wants to.

DivinDriver

iTrader: (15)

...Fuel filter...