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IH T444E Performance / Fuel Supply

15230 Views 7 Replies 3 Participants Last post by  tanky
Hello all... I recently picked up a 1997 IH 4700 with the T444E in it (~110k miles). The truck's "get up and go" is terrible compared with another identical truck that I test drove and it maxxes out at around 63 mph on the flat. I know that IH can program a limiter on the truck for a certain speed that will simply cut out acceleration over that speed, but the last owner of this truck (who used it as a fleet vehicle) said that he had his mechanic limit the speed by "turning a screw on the fuel pump".

Any truth to this? If so, where is the fabled screw and how to I appropriately tune it? I would assume that there is a fuel pressure regulator for pre-injection pump pressure (since there's a Schrader valve on the line at what looks to be a filter), but I am not sure how this would be adjusted and I haven't found any good info on this online.
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The presious owner is either lying or clueless because there is no screw, it's ALL electronic.
John, thanks for the info. Hopefully on the clueless side. His company had had a fleet of 11 trucks, and probably some of those did have mechanical regulation. Pressure measured at the Schrader valve by the filter was 55 psi, which is (I guess) around normal. Could what I described above be a fuel supply problem, i. e. filter(s) restricting flow? Thanks.
Fuel pressure is good at idle or no-load but may not be there under load. Check the "rock catcher" on the side of the filter housing for debris, any debris.

Trucks are "built to order", and it's possible that it has a 170 HP rating, steep gears and small tires = SLOW truck.

If you can get the "last 8" of the VIN, I can run it and tell you what it was built to.
Thanks John. I'll check the filter; I do also think that there is a problem with fuel supply under load. I'll check on "rock catcher" on Saturday... see if I can find it and figure out how to get into it. One question, though... how do you prevent air from getting into the system when cleaning it out?

I will also replace the fuel filter, but for that I need to get to a dealer, and my nearest one (20 miles) has hours of 9-5 M-F, which is not going to work well.

The sticker on the side of the engine is punched out for 190 HP, so it's the middle model for the year, I guess. I will PM you (John) the last 8, also... thanks much.
The rock-catcher is easily removable with a 15/16" box-end wrench (as I recall) and it's a "pre-filter" that is only the size of a kiddy cup so there's no concern about air in the system.

The filter is readily available from NAPA or another quality parts house but I don't believe the IH and Ford 7.3L PSD filters are directly interchangable so be sure you get the one for an International.
my T444E stopped while driving. and sat for over a year. cranks fine, doesn't fire. fuel filter housing is empty with a little fuel in bottom. replaced filter, still won't fire. is there a screen on the fuel line pickup in the fuel tank? how does the 'rock catcher' clean out? do i have to remove it from the filter housing? should i put air thru the fuel line backward into fuel tank to see if there's a clog? i'll have to do this just to satisfy my curiosity since the factory manuals DONT even say if there is a screen....gawd! so, after i find out that there is no clog in the fuel line, can i just disconnect the fuel line from the pump to the filter housing to see if the pump is working, or will that prove nothing since the fuel lines are full of air?? i've been told the housing has to be filled to prime the pump... what is the actual truth? i just want to find the fault, there are no codes, it has to be bad pump or clog in line , right?
pictures on the net show no screen on the fuel tank pickup
the pre-strainer should unscrew and be e z to clean
the truck runs with 1/8th an inch of fuel in the tank
but pictures of the pickup show stuff hanging off it that would keep it from going real close to the bottom of the tank
i've run out of fuel, the tank gets BONE dry
why are people afraid of running out of fuel?
what is scary is the truck exploding in seconds or driving away on it's own due to the bleeting crank inhibit relay
the cam position sensor ain't no thrill either
it took me 2 hours to replace that simple thing
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