Well after re-doing the Banks turbo last year, I decided to try a "stress test" - made a 1-hour run to pick up 3200lbs of stuff. Didn't make it back - truck drove fine until I hit the highway, got to high gear and it just folded up.

One expensive tow later and it yard drives fine for a minute or two but won't pull any load or climb the smallest of hills. My friendly mechanic tells me I need an injector pump. Guess that makes sense as the pump did seem pretty hot.

This brings me two questions for the group -

First, is there any point to an uprated pump on a 6.9 engine? I plan to run pretty heavy (slide-in camper plus car trailer) on trips from Mass to Ohio, Nebraska and maybe DC; I suppose I would rather "wait" than kill economy but haven't actually done a run loaded up like this yet. I do plan an e4od swap to keep the highway runs from being "pinned all day".

Second, reading here it sounds like folks swap injectors at the same time, but my guy says he's never done that - if it's not misfiring (and it's not) they're AOK. Any thoughts?

Best of the season to all,
- Jeff

 

When was the fuel filter changed last? air filter? If it is falling flat on its face like that it I don't think it is the ip. Seems to me that other things could be at fault here. Do you have good flow from the schrader valve on the filter housing? Of course if they have never been changed it is probably time to replace the ip and injectors.

Any good diesel shop or repairman will recommend to replace injectors at the same time. Changing an ip without doing the injectors(when you dont know the last time they have been replaced) is like changing the oil without changing the filter. Others may disagree but that is how I've always done it whether its my truck or the tractors on the farm.

 

X2 Injectors are cheap, its good insurance for one. IDI injectors dont "break" like new ones do, they just get worse, and worse, and worse, and worse. Ford /IH specs a checkup on pump and injectors at 65k and replacement at 130k. How many miles on the engine?

You will need head studs if you dont have them. Then crank up the pump. My advice, pickup a 80 or 90cc pump and matching injectors from http://www.idiperformance.com. The only place you will KNOW youre getting what you paid for - replaced / rebuilt parts to factory spec and pressure matched injectors.

 

Thanks for the questions:

- under 500 miles on thermostat, fuel filter, turbo, return lines, glow plugs & controller
- unknown mileage on engine, guessing 283k on the truck but the engine is a Jasper
and it's clearly been in there some years
- schrader gives a steady 5psi

My buddy does lots of diesel work, as well as gassers. I tend to believe it may not be necessary to change injectors but it does sound like good practice. I think I'm going to wish we'd done that when the turbo was off - can you actually get to the back ones with the Banks still in place? He does not always appreciate my attempts to be thorough - I could not talk him into doing head studs while we had the top apart (manifold gasket is what started all the top work), and no, I'm not going to tackle any of this myself (no place to work on it).

The way it falls down makes injector pump seem rational to me. Especially since the pump gets pretty hot, and the hotter it gets the worse the power loss gets, and I have no idea of the history.

Thing is, would an uprated pump really do much for me with the smaller displacement? I don't think I'm out of fuel adjustment on the stock pump, and until this it ran fine with no smoke at idle and a little haze at wide open...

More power might be nice but I'm at 13mpg (empty) and I'm swapping to an OD trans to try and get a couple mpg's back - these long trips will eat a lot of tanks...

Thanks,
- Jeff

 

Your foot detirmines power and mileage (beyond tuning and overall engine health). Turning up the pump simply allows you to have potential for more power, and therfore worse mileage - potentially. Doesnt matter if you have a 50cc pump or 500cc. The displacement difference is negligable, with a turbo, non-exsistant. The thing is, 6.9 headbolts suck and anything more than 10-15 psi is considered pretty risky. (thats why the wastegate is set to 9.5) A stock pump will do 80-90cc if its healthy, the benefit of buying a 80 or 90 is its calibrated at that rate, which affects dynamic timing and fuel curve.

Friend or not, i would find a different mechanic, or somewhere to do it yourself. Headstuds on a 6.9 is pretty much day one, diesel 101. If i were in your shoes i would get a stock calibrated pump and bump it up half a flat (assuming pyrometer). If you want to put studs in it i would jump up to an 80 and crank up the wastegate.

As far as changing injectors, i dont need to debate the merits of changing them, when, and how often, i already know, and have seen proof first hand. You should be able to get to all injectors and glow plugs fine. You will have to pull the filter box, but the turbo should be fine... if not that would be a pretty retarded design. I would consider overtorquing the headbolts 10% if they were replaced.

 

I'd replace injectors too... I've got a pop tester and have seen first hand what old injectors tend to do... they tend to leak, and some will wear faster than others. This results in varying pop pressures, which affects timing(for each cylinder) massively. With a set of worn injectors, you can easily have a situation where the engine is fighting itself; one or two are firing too early while the rest are firing too late.
Or, you can simply have everything too early or too late, depending on how you time it -- usually you use cyl #1 to time the engine, so whatever that injector is at determines the overall timing.

These aren't Powerstrokes; the injectors are cheap and wear items.

 

i agree with the guys here. when changing injector pump change the injectors.
they are only really good for around 125-150k miles.
an easy way to tell if it is the injector pump is to run it. once it dies or looses all power, pour cool(NOT COLD) water over the injector pump. if it regains power, the injector pump is shot.