View Full Version : Fuel pump

08-09-2014, 03:38 PM
Ordered a fuel pump from Rock Auto. Shipped quick and looks to be good quality - really good - couldn't beat the price anywhere.

Supposedly has the type of seals that will not disintegrate with the ethanol in today's fuels. 1 year guarantee - that should be long enough to tell.

Airtex 3461 with the vac booster.

Lever isn't quite the same (a bit straighter) - won't have as much lift from the cam. Don't care as long as it works. Should have taken a pic.

All went well - only took about 3 hours to replace. The A/C bracket made it take a little longer than I expected - still - not bad.

Now comes the question. The hose barb on the inlet is 1/4 inch - everything else is 5/16. Can anyone confirm this is original or not? As far as I know I have the original hose barb that I have been transferring to the new fuel pump over the years (this is the 3rd pump).

Had been thinking my new "see through" filter might be 1/4 inch and causing a bottle neck in the flow but it is 5/16. (and yes it was fun pushing that 1/4 hose on the 5/16 fuel filter :mad: )

What's the difference in fuel flow between 1/4 inch and 5/16?



OD of hose barb in the center

08-09-2014, 05:32 PM
Originally it came with a rubber hose with the end pressed on that screwed into the pump.


08-09-2014, 06:35 PM
Interesting - Thanks John.

That barb has been on there since '94 for sure - no telling when it was added.

I'll keep an eye out for a 5/16 barb with the correct threads.


08-09-2014, 07:57 PM
Believe me, your engine will never know the difference between 1/4" (4/16") and 5/16" diameters. Even at interstate highway speeds, 1/4" is more than enough to feed your carb.

Did you ever rebuild your carburetor and notice the size of the fuel supply needle & seat? It is way smaller than !/4".