Fuel Delivery?

OldSchoolRodz · #1 (**permalink**) 02-01-2009, 03:06 AM

K Fellers;

I was breaking my build budget trying to build my original Y with vintage speed parts; so when I found a rebuilt 53 Chassis / Flattie for cheap, I decided to drop my 55 F100 cab and bed on it to try to get her on the road.

I'm new to Flatties. This engine had been sitting indoors a few years in the truck since the rebuild, and gas had varnished up the old Carbs fuel bowl / float. I replaced the Carb and fuel pump with an NOS Carb and good quality USA made pump before I tried to start it.

I started her up and she ran fine; but to keep her running, I had to feed the carb thru the air horn. Doesn't seem to be pulling enuff gas from the tank, or pushing enuff fuel to the Carb.

I've come up with a couple ideas / possibilities maybe one of you experienced Flatsters can reality test.

I've considered two possibilities; that the old gas settled in some low spot in the metal gas line and gummed it up / partially obstructing gas flow or, have I read somewhere that there's a pushrod that rides on a cam lobe that can wear out of tolerance and reduce fuel flow?

Keep it Kool, Keep it Old School! Thx, David

tinman52 · #2 (**permalink**) 02-01-2009, 04:31 PM

Most likely you have debris in tank,try to blow back thru line w/ low pressure air w/ gas cap off. May also be fuel pump. New ones are all made in china and most are junk right outta the box. Electric pump maybe? Also check needle/seat in carb inlet,may be stuck. Let us know what you find. T/M

Snowking · #3 (**permalink**) 02-02-2009, 10:19 PM

Remove the fuel line close to the carb, crank over the motor and see what you have squirting out but yes it is always a good idea to clean the fuel system lines and tank, maybe try hooking up a jerry can to your fuel pump see if it runs off that.

OldSchoolRodz · #4 (**permalink**) 02-03-2009, 11:28 AM

I have a weekend project! If I'm gonna I start pulling fuel lines, I should make sure the bottom of the tank is clean. It a nice rust / dent free tank that looks like it was replaced at some point. What can I use to clean any varnished gas that settled in the bottom of the tank while it was sitting, while I'v got it apart? Thx, David

tinman52 · #5 (**permalink**) 02-06-2009, 10:09 PM

I used laquer thinner in mine, about 2 gallons. Let it soak for a while, then slosh it around,drain it. Repeat. Mineral spirits are a lot cheaper, but don't have as much "bite". Or take it to a radiator shop and have it cleaned $$$. Good luck. T/M

effie_man · #6 (**permalink**) 03-03-2009, 08:19 PM

do the jerry can thing to find out if its the pump (maybe the diaphram is dried out), if not the pump then id start checking lines back to the tank. the psuh rod for the pump could be worn out a little bit, Ive hears that a little trick is to glue a piece of leather at the end of the rod to take up the slack from it being worn

petey shoes · #7 (**permalink**) 03-04-2009, 08:59 AM

if carb was varnished up, then fuel lines are also gummed up. once tank is clean, run new line.

OldSchoolRodz · #8 (**permalink**) 03-05-2009, 12:35 AM

Thx, thats what I was thinking! Believe I just need to pull the tank, replace the lines... come spring.

Keep it Kool, Keep it Old Skool. David