1970 carb

[crawlin cruiser]

Just finishing up a build on a 1970 fj40 and I'm having a problem with the carb draining fuel while sitting. It runs great otherwise. I've taken the carb apart to flush everything. Any ideas??

 

[crawlin cruiser]

If I cant get this sorted, can I use a carb from a 74 (1.5F) ???

 

[Pin_Head]

It is a common issue. My feeling is that it is due to the use of reformulated or oxygenated gasoline. It is more polar and has a higher surface tension, so it will creep out of the bowl through the idle / slow circuits. Try using straight gasoline if you can get it in your area.

If you can’t find straight gasoline, you can make it by mixing reformulated gasoline with water, 4:1 with 4 parts gas to one part water. Then siphon off the gasoline. This removes the ethanol and other polar components of gasoline. It is a PITA, but might be OK for small engines where you don’t want oxygenated gasoline siting for a long time.

 

[thebigredrocker]

x2 I've seen dozen's of threads mentioning the fuel bowl draining issue. 74 carb isn't set up to use a cable style throttle. So you'd need to modify it to accept the cable or find a 73-74 mechanical style throttle linkage. Would suck to go through that hassle only to find the 74 bowl siphon's also.

 

[Dizzy]

I'm going to treacherous territory, but wouldn't an electric fuel pump come in handy here, with the key at "on" for a bit to fill the bowl before you kick the starter?

 

[crawlin cruiser]

x2 I've seen dozen's of threads mentioning the fuel bowl draining issue. 74 carb isn't set up to use a cable style throttle. So you'd need to modify it to accept the cable or find a 73-74 mechanical style throttle linkage. Would suck to go through that hassle only to find the 74 bowl siphon's also.

So that being said... the truck is a 74 with a 1970 f installed. It still uses the 74 throttle assembly

 

[thebigredrocker]

well that's good news.