Hey guys i need your help on something... first and foremost i have an

1989 ford f-150
5.0L 302 engine
EFI
2x4

alright on to the problem my truck ever since i got it roughly 2 yrs ago has never had a working secondary tank. which i want to get fixed. i obviously think the problem is the fuel pump since when i switch tanks my truck sputters and shortly dies there after. so obviously its getting no gas.. anyways i was afraid to do it since i didnt really want to mess with taking down the gas tank and having to go in and hoping to do it all right, recently to my surprise i learned that on efi models 86-89 the fuel pump was mounted externally from the tank and on the line. so i thought i would give it a try.... but now i went to the advance auto parts website and it keeps saying im going to need 2 fuel pumps one in and one out... so im not sure if thats the case or if its wrong and my haynes manual is right... help please i would like to get this fixed especially since my fuel gauge doesnt work(hasnt been fixed again since i dont really want to take down the tank to replace the floater...ive done alot of mechanic work on her but this seems out of reach)

hey if you guys can forward this to my email i'll be able to read it faster vdelaguera@yahoo.com

 

I'm not sure I understand what you mean by "one in and one out". I'm not all too familiar with the older trucks but I do believe that the fuel pump is in fact outside of the tank in an 89. I know that on the newer trucks like mine there are actually 3 pumps, 1 in each tank and 1 on the frame rail. Perhaps this is what you're confused about...?

 

well on the website it says that one pump is required on the inside of the fuel tank and one extrenatlly mounted.....from reading all the topics i could find about fuel issues i figured that both tanks have a low pressure fuel pump mounted within the tank and then there is one high pressure one mounted on the frame rail... which seems to make sense only that im not sure if it applies to my truck since in my haynes manual it simply states it as if there is only an external fuel pump for each and thats all... so im trying to see if replacing the fuel pump is as simple as just getting under my truck or if im going to have to take off the bed or drop the tank

 

'89s actually have 3 fuel pumps (dual tanks). 1 low pressure pump in each tank, and a high pressure pump on the frame rail. If you can run off the front tank, then the high pressure pump is good, so all you would need is the fuel pump in the rear tank.

 

Chris, you're so confused.

1989 and earlier has one internal feeder pump per tank and one external high pressure pump. 1990 and later has one internal high pressure pump per tank.

 

so the way to fix it would be to drop the rear tank then? hmmm is that honestly hard. i mean the rear tank has no gas in it since it has long since been siphoned out.

 

Dropping an empty tank is probably easier than taking the bed off. If the truck is rusty, it's going to be a pain no matter how you do it.

 

Lol luckily luckily very luckily the previous owner at some point had the whole bottom undercoated. and the truck has no rust what so ever except for a bit of the roof over the passenger side..... im sure i can look up the procedure for dropping the tank in my haynes manual but is there any advice you would reccommend, specialty tools etc.

 

I knew I'd screw it up At least I bumped his thread into your attention

 

Just did mine and it wasn't as bad as I thought.Instead of
splitting lines(I didn't have the tool) I lowered tank to a point that I could reach lock ring and blocked it up making
sure there was slack in lines. Removed ring and lifted out
entire pump assy. and unbolted pump from fuel sender and
bolted new pump in place along with fuel gauge sender.Then I spliced the 2 pump wires w/supplied butt type connectors, plugged in gauge sender wire,and wiggled
assy. back into tank. Locked in place w/ ring and raised tank/skid plate assy. back up and bolted it up.Just be sure to pull lines away from tank as you go up or it will pinch or kink lines and after you start truck the pressure
build up will blow gas out and you'll have a lake under
your truck in a heartbeat.I know cause that's what happened to me.Dropped tank again to unkink hoses,raised up again ,pulling lines away and bolted up
again.started up and no leaks . Friend who helped me said he took twice as long on his truck cause he had a hard time disconnecting the lines even w/the tool and me doing it twice cause of kinked lines.Hope this helps
and good luck.Aloha from Maui,Hawaii

 

just a small suggestion, but check the selector switch...on my 90, my front fuel tank went "dead" i thought it was the fuel pump..so I just kept running off of the rear tank..finally got around to dropping the center tank to change the pump, got her all back together.. poured 15 gal of gas into the tank, and still dead..went nuts checking wires, fuses, relays etc. then I pulled the selector switch.. contacts were all burnt up in the back..strange thing was, the guage still worked.. showed the correct amount of fuel for both tanks.. got a new switch from Ford, both tanks work great now..plus one has a new fuel pump! the pump needed to be replaced anyway.. it made funky noises when the tank got to 3/8, 1/2 tank..

 

interesting.. would be cool if you guys lived near by :-p i'm probably going to go for it and see what happens and try to get a friend that might know what to do... and if its easy enough ill drop the front one and also fix the sender on that since right now my gauge doesnt work at all.