4x4flatbed

It will run fine under half throttle and lower rpm but as soon as it gains some revs it bucks and falls on its face, shift up with lower throttle input and runs ok. At idle fuel is about in the middle of the sight glass on the carb, give it some throttle and it instantly sucks it down and almost cant see fuel in there. If i pinch the return line off the pump it fills the sight glass. These mechanical fp's are internally regulated right? I'm thinking thats my problem and i just need to replace the pump but wanted to get another opinion before spending money right now. Thanks

83Toyota88

iTrader: (1)

Could be a fuel pump or a carb problem. Possibly the float.

kawazx636

iTrader: (3)

Have you checked your fuel filters? They could be clogged up

4x4flatbed

fuel filter is brand new. I set the float a couple months ago when i first got the truck running and i beleive its still set right because its where it should be at idle and comes back up when you pinch off the return line

83Toyota88

iTrader: (1)

Sounds like the high level setting on the float is correct but I was referring to the low level setting.

jimmyjoebillybob

With those pumps, must of the time they will dump fuel into the crank case. Pull the dip stick uot and see if it smells like gas

4x4flatbed

havent had time to really mess with the truck lately but just checked the oil and its normal, no gas in it. im going to reset the floats again and see if that helps anything. I was also thinking about putting a regulator on the return line, has that been done successfully before?

4x4flatbed

just went out and worked on it a little, set it up to spec, still low so i started taking .5mm out each time and then realized i need a new float, the low level tang is too weak and letting the float fall too far. Never would have guess a float would be $40 though!

83Toyota88

iTrader: (1)

Yea its crazy what they cost.

4x4flatbed

well i got a new float, set at factors specs 9.5/48mm. still almost no fuel in the bowl so i lowed each of them a couple mm to about 7.5/46 and now have a little fuel in there but still cuts out, bucks and dies on hills or with a load on it. maybe im looking at setting it up a little wrong. can i get a little refresher on how to set the float? like which tang adjusts the high level and which the low, which way allows more fuel in the bowl and things like that. i have searched and cant find what i need. my dodge exploded the front driveshaft and punched a hole in the trany last night so this needs to take over as my daily for a little but and im getting real frustrated with it. thanks

83Toyota88

iTrader: (1)

Download the FSM in my signature. In the pdf called chapter 3 on page 28 it shows how to adjust the float.

4x4flatbed

i downloaded it and it says the same thing as everything else i have seen. like i said i tried setting it to factory specs and that didnt work. what i need to know is which setting do i need to adjust to let more fuel in? and which way to adjust it

83Toyota88

iTrader: (1)

Factory specs didn't work for me either. Had to play with it. You should have to bend (B) of the float, per the FSM pictures, downwards (towards the float not away from it) just a tiny tiny bit at a time to allow the float to raise up and let more fuel in. Fuel level needs to be half in the sight glass or just a hair under.

4x4flatbed

thanks, thats the kind of info im looking for. i bet i have had it on and off 40 times already. right now i have it so that the fuel is in the upper part of the sight but just with throttle in N it will suck it down and sit there and idle with barely in it and if you drive it, still falls on its face and dies. just had to idle up the hill in 4lo 1st to get it home. ill try playing with the "B" tab a little more. i still feel like my fuel pump might be weak though, i have a see through fuel filter and its only about 1/4 of the way full when its running. the filter is before the pump

4x4flatbed

should of listened to my gut lol new fuel pump and shes running better then ever. stupid thing made me feel like a idiot, owell lesson learned