What size fuel line for a carb'd 300?

[JimJam300]

Hey guys I had a valve cover leak and I decided to get at it, and part of that is removing the pump-to-carb fuel line. The compression nuts on my line were seized and I ended up having to cut the line to remove it. I thought I'd just go to the junkyard and pull another out of the E150 I saw a couple weeks ago but it was gone, and now I have no pump-to-carb line.

Anyone know the fuel line and compression nut size for a 300? I read somewhere that all engines up to 302 were 5/16 but I don't want to bite a $40 bullet.

[ratdude747]

It is 5/16.

On mine, I bought barbed fittings for the carb and pump and ran rubber fuel line with a clear filter (lawn tractor sized/type). $20 or so at the local O'rieleys in total. I did this because the factory line was a basket case, I was tired of leaky steel filters, and I was trying to combat vapor lock. The pump uses an adapter fitting for the flared connector (match it up, can't remember the exact size/term), the carb uses a 1/8 NPT barb.

If you go this route, in my opinion, avoid the Mr. Gasket glass cartridge filters. I ran one of those, and in addition to letting a bunch of fine silt into the carb, after 9 months the glass cracked and leaked fuel everywhere. I since swapped to a lawn tractor "universal" filter and have had no issues over the last several months. Much better filtration than mr. gasket, no glass to crack/come loose, and still getting adequate fuel flow. Plus I can still see what sorts of junk is getting pulled from the tank.

[myrl883]

Fuel pump to carburetor is 5/16".

[JimJam300]

ratdude747 wrote

It is 5/16.

On mine, I bought barbed fittings for the carb and pump and ran rubber fuel line with a clear filter (lawn tractor sized/type). $20 or so at the local O'rieleys in total. I did this because the factory line was a basket case, I was tired of leaky steel filters, and I was trying to combat vapor lock. The pump uses an adapter fitting for the flared connector (match it up, can't remember the exact size/term), the carb uses a 1/8 NPT barb.

I don't know why I didn't think of this... Yeah whoever got to the carb before me stripped the flare nut and I had to use vise grips to remove. I think I will do a permanent metal line in the far future but I really just have to get my truck on a trailer to move to my new house for now.