So I recently got a 86 F250 460 4 speed with a 6" lift and 35s. It's a great truck so far except going down the highway it starts to bog down in the top rpms of 3rd and 4th. The guy before me said it was the jets in the carb so I swapped it out with one I had. It helped a little bit but it still bogs down. My next guess is the inline fuel pump because it's making a really loud ticking noise when the key first is turned and while running awhile. Any help would be very appreciated

 

The 460 trucks didn't have inline fuel pumps you can see, they were in the fuel tanks. Or they had a mechanical one on the engine.

Some of the aftermarket fuel pumps tick, that's how they work. I suspect they stuck that external fuel pump on there and are pulling the fuel through the old fuel system. Which would mean they are pulling fuel through the old pumps inside the tanks.

 

Which will mean the fuel flow will be restricted and the engine will have problems at higher RPMs, ask me how I know this....

 

How do you know that haha

 

When I first got my truck - and I knew absolutely nothing about it - I got a replacement rear tank + sending unit from the local JY.

My truck is a 1981 and has a mechanical pump on the engine and a "small" hole in the gas tank for the sending unit.

The replacement stuff I got from the JY was from a mid-80s that had an electric pump in the tank and a big" hole... I quite honestly didn't know what that device was, I couldn't imagine sticking an electric motor into a tank of gasoline and expecting it to work without creating a fire yet there was this device there with electric wires going to it...

The nylon filter on the end had broken off (on the JY replacement stuff, the pickup tube) so I improvised and put an old sweat sock on it, grafted the new wiring connector into the stock harness, and installed the sucker.

Surprisingly enough, this all worked up until ~3,000 RPM (while pulling a trailer full of firewood up the mountains) when the engine started gasping like it was running out of gas. Because that rear tank/pump/sock assembly was the most recent change, I knew where to go looking for fuel delivery issues - and some learning about electric, in-tank fuel pumps.

Seriously, that's what happened..... I no longer engage in nor support nor help others with redneck, backyard hacks like that, I have learned a LOT since I got it in 2005.

 

I would not be against pulling the sending units, pulling the pumps off and putting a line to bypass where the pump was. But you have to be careful doing that also, try and use steel line if you can. If you use hose it must be rated for submersion in gas. Some of the fuel lines you buy only have a fuel rated inner liner, and the outside of the line will not hold up to the fuel.

 

So I replace the after market inline fuel pump and it helped a lot but now it's back so I'm guessing it's the in tank one, so I'll try that next