I finally ordered up a diesel timing adapter...coming on a slow boat out of England. Should be here in 2-3 weeks. I'll get the timing in spec, and then go from there. Should be about the same time that my bonus check rolls in, and depending on how things go, I'll probably order up a new set of injectors at that time too.

 

Consider doing the pump at the same time. New injectors, old weak pump could cause performance problems. Same with new pump old injectors. There are several good threads on changing the pump out.

 

I've been going back and forth on that a lot. What keeps me from fully pulling the trigger is those pumps are a LOT of coin, and it doesn't seem like the pump is having any issues right now. It fires up almost instantly when hot, and power doesn't seem to be an issue. The only reasons I'm really even looking at injectors right now is my recent cold no-start issue, and to a lesser degree, that the MPGs are in the toilet. Thankfully it's in the driveway right now, where I have easy access to electricity to recharge the batteries/hook up the booster...but if it happened at a remote campsite??? I'd be up the creek. At the end of the day, I don't care about it making max power, and MPGs aren't a huge concern to me...I just want something reliable. I'm just thinking that the low MPGs are pointing to old injectors likely not spraying correctly.

If we were talking about a $100 gas pump, I'd have already done it. But $700 is a bit much to swallow as a just in case kind of thing, since there's no good way that I've found to be able to test the pump for performance. I'm already not wild about the idea of dumping $400+ into a very low use vehicle on a guess that this or that is wrong. Making that number $1100+ doesn't make it any easier to swallow, lol. I've never been one to "throw parts at it until it's fixed", and I don't like becoming one either.

On the other hand, these pumps appear to be pretty simple to swap out, so if I do run into issues after putting injectors in, I can always swap it out later.

Unless we're talking that an old pump could somehow damage new injectors?

 

The theory is that new injectors will finish off an old pump. The fuel economy doesnt make sense, mine has never gotten great mileage, at 14-15, but even towing heavy i dont get anywhere near 9. Lowest ive seen was like 11.7, towing a car, bed load of stuff including a tall freezer catching the 20-25 mile an hour headwind doing 80 on the freeway. She was squated pretty good, so i was catching wind like a sail.

 

With 3.55 gears Empty is about 16 loaded about 12.

 

Well that puts me about on par with you, 3.73s and 255/85s (34") tires. ZF. Now that i have all the power i do with the new engine, strongly considering finding a set of 3.31 gears out of a newer SD. Would require me to go from 50 guts to 60 guts in the front end though. Might have to look, maybe you can get 3.31s for a D50

 

I really don't see an issue with running a new pump with old injectors; what's the increased pressure going to do to a tired injector? Dump a bit too much fuel at the worst? Turn back the pump if so.
When I sold my '84 it had an even 300K on it. Original injectors, second pump. (Pump replaced @ 200k) Ran perfect, good power, good mileage; although towards the time I sold it it did drop a bit in mileage, about 1-1.5mpg IIRC.
But new injectors with a used pump, I could see where that could cause problems.
I agree with not dropping the cost of a replacement pump when the old one's working fine; as costly as they are I get all the mileage I can out of them. Maybe consider just testing, inspecting, and cleaning your old injectors; they're really simple.
Spray pattern's not relevant to an IDI since the combustion happens in the precup, not in the cylinder. All that's important is that the fuel gets in there.
Could start issues are more likely to be glow plug and/or air intrusion related.

 

That makes sense. About new pump old injectors. If I ever do anything with mine. I will more than like do both and be done with the fuel system, but that will be because of failure

 

That makes sense. About new pump old injectors. If I ever do anything with mine. I will more than like do both and be done with the fuel system, but that will be because of failure


Just for fun just checked prices on a new 150 and 250. Guess I keep driving mine 34 k and 48 k

 

Thats just it, the old injectors may seem like theyre working fine, and maybe they are doing an ok job. Because of the IDI design there is alot of leeway in how the injector actually performs, we dont have to have the super atomization the Di engines do, this is why i say the moose injectors are pointless. Not saying they dont make a difference, but the difference is negligible. Regardless, wear out they do, they pop lower (alot lower) they dont "inject a mist of diesel" so much as they **** out a stream of fuel. They leak, they form droplets etc. This can cause rough idle, harder starting, loss of mileage, increased emissions, high egts etc. The issue is, the wear is so slow, you dont notice how much worse it has gotten. They dont "break" typically, unlike DI injectors, they just slowly get sloppier and sloppier. I think justin told me one time he popped a clapped out set of injectors he got as cores and they popped at like 800 and were all over the place.

But the facts are this, for service manual spec'd the injectors and pump to be tested at 85k? and replaced if out of spec, then replaced as a whole at 150k. Im going off memory on the numbers. If youre dropping the coin on a new pump, why wouldnt you change the injectors? Yea, a pump and injectors cost a little bit, but nothing on building a 460 to suit your needs, nor replacing injectors or hpops or pick a thing in any of the newer diesels. Not to mention you dont have to worry about mice eating spark plug wires while it sits, or cam sensors going out, or mice eating computer wires etc. Im having a hard time keeping up with the OP, he claimed fuel mileage was a non issue, was going to go 460, but now wants to spend money on injectors to improve fuel mileage?? If it does what you want leave it alone. If it doesnt, fix it. I would recommend doing the pump and injectors together. Sure do pump this month injectors the next, but i would change them out together.

 

You're absolutely right...I have been all over on it. As I've said from the get go, I don't really know how to deal with diesels. There's no good way that I can see to test the pump, and an injector tester is pretty much the cost of a set of injectors anyways. I don't have a frame of reference to what the truck SHOULD be doing. I don't have a clue whether this thing is running exactly as it should be, or if it's way off the mark. I don't want to throw a ton of money at an issue that doesn't exist, and all I've wanted from the get go is just a reliable truck that I know is going to start and go every time I need it to. Up until I started fiddling with the timing on it, it seemed like a truck that wouldn't work for what I wanted it for, and I didn't want to throw 2 grand worth of parts at it, and still end up with a truck that didn't do what I needed. Then I started fiddling with the timing, and saw that things were moving in a positive direction. At least now it has the power to pull the weight, and EGTs are closer to where I think they should be. So I ordered up the timing pulse adapter to dial it in farther.

Fuel mileage isn't a concern as far as costs go, or comparing the mileage between gas and diesel, because I just flat don't drive the thing enough for it to be a major difference. I mentioned the MPGs as one of the several factors that led me to believe it may well be time for new injectors, not THE factor. Even then, it's the reliability that I'm going for, not an increase in MPGs. If the truck is supposed to get 8-9 MPG, then great..it's running just as it should. But everything I keep seeing here says that it should be running around mid teens unloaded, so that makes it appear that there's an issue somewhere. But replacing parts just for a MPG increase would be foolish for me, as it would take me about a decade to even break even on costs.

Nor am I looking at "building a 460 to suit my needs". Frankly, I said 460 because it's a Ford forum. Plain and simple. Realistically, if I were to buy another truck, it most likely would have been a Chevy with a 454 in it. The bone stock '89 C3500 I had years back did all of what I'm doing now without a problem, except be a 4x4, lol. But I know gas engines. I know how to troubleshoot gas engines. I know how to diagnose gas engine problems. I know that a bone stock TBI 454 does what I need it to do, and when I go to test drive one of those, I know if it has issues or not based on feel.

But I feel like I'm finally getting close on this truck. It may well be that once I get it timed on spec, and get the glow plugs & harness changed out, it may well be just fine as is. I'm not replacing anything else until the timing adapter shows up, and I see where it's sitting at timing wise.

 

to find an Idi mechanic, go to the school bus barn start talking to the guys ask for the old timer. Get to know him.

 

If that's all you want, an IDI is pretty good at it. If you have solid batteries, cables, glow plugs and wiring, starter, and half decent pump and injectors these trucks just plain work. The reason you often find them in such neglected condition is because they will take an immense amount of neglect and forgone maintenance and still just plain work to get from A to B.

When I got my truck it was a turd and burned an inordinate amount of diesel. Just settings the timing frmo where it was (retarded at 6.5* at 2000 RPM) to a more appropriate 9* at 2000 RPM it made a lot more torque off idle and cut way down on smoke and fuel consumption. I only later replaced the pump and injectors with performance parts when it developed a no start when hot issue, a typical symptom of a worn out pump. That improved performance immensely while maintaining MPG. It's still a slow old smokey diesel but it drags my boat around well enough and just plain works every time. The reliability is a prime reason I chose an 80-97 pickup and specifically one with no electronics.

 

As I said earlier, I'm not doing squat to it until I get that timing adapter, and can verify the timing/adjust as needed, and then see how it's running. It's entirely possible that I started at way retarded, ended up way advanced, and now am running somewhere around 0. Or maybe not..I don't really know, lol.

But what I do know is that I was really close to just parking the thing, and buying another truck before I started down this road. It was frustrating...by appearances, it seemed like it was running perfect. Had acceptable torque off idle, but completely lost it's ***** by 50mph, even unloaded. It made zero sense when looking at exhaust, looking at EGTs, and looking at MPGs (and again, only using MPGs as an indicator of performance, or lack there-of). Most people suggested throwing roughly $1500 worth of parts at a truck with unknown history, and I still didn't know what it SHOULD have felt like anyways. For all I knew, it WAS running exactly as it should have, and I was just asking too much of it.

Then I finally said the heck with it...if it's going to be parked anyways, then I have nothing to lose by cranking up the timing and see what happens....and it made a positive net change. Fiddled with it a bit more to get it to where it is now, and I felt like the $160 gamble on a timing adapter was worth it.

My thinking with the injectors is either popping off early due to weak springs, or possible leakers. Of course, the early pop off can be mitigated a bit with a timing adjustment. But again, I'm really just thinking openly until I can check the timing.

At the moment, this is the newest vehicle I own, out of 5..unless you count the 2002 motor in my 1987 Samurai. But that's just a play toy anyways. Even my daily is an '87 Pontiac. The newer stuff just doesn't do it for me. I think once I get a better understanding of how everything works in here, it'll be OK. And I've found it IS pretty difficult to find a crew cab 4x4 anything with a manual trans any more, gas or diesel. So if I end up having to drop a grand into parts on this thing to make it reliable, so be it. Still cheaper than another truck, lol.

 

Well I'll be...for randomly playing with the timing, I ended up getting it at 10*, lol. The timing meter showed up the other day, and I just hooked it up today. I was going to back it down a smidge, but can't find the wrench I made for the pump nuts.

In related news, I found I have a minor fuel leak near the lift pump, and what looks like a rear main seal leak....it never ends with this thing, lol.