1989 S1600 x Uhaul truck 7.3 IDI

[TNBrett]

The last two pics the OP posted were pics he found in a search. The first one that looked new, appears to be a newer model for electronically controlled injectors. The timing isn’t adjustable because the computer tells the injector when to fire. The tan one looks to be on a 4cyl John Deere industrial engine.

 

[IDIBRONCO]

The first one that looked new, appears to be a newer model for electronically controlled injectors. The timing isn’t adjustable because the computer tells the injector when to fire.

That makes perfect sense now. Sometimes I just need to see the "+2" in order to get the "=4".

 

[gandalf]

...

I have a theory. We'll see if it pans out tomorrow. Somebody in the higher up Uhaul knows about the OilBurner site and said they had to find a way that the timing could not be easily advanced or any oilburner that rented one would be under the hood as it is pretty weak with a large load.

...

I think I got lost somewhere along the way here. Are you saying that UHaul modifies or changed the mounting flange on the IP, the one which mounts to the timing gear, that they modified it so the timing could not be changed?

I've been running a UHaul IP for a number of years. I guess I was one of the lucky ones who got a good one. Mine is fully adjustable, as much so as a normal IP.

 

[Big Bart]

Ok. Yep, those bolts were for the gear. It's been 3 years. I remember now I had to special order a 12 point socket that size as normally available are all 6 point.

And yes, that top "nut" that can't be removed without sliding the IP back a bit is on a stud. Don't remember but makes sense that the other two would be studs also.

The triangle flange picture was not of a DB2. It is a Standadyne and was posted just to show all Standadynes did not all have slots. I could not find a DB2-4814 that showed the holes. Will be calling the place where I bought it tomorrow and ask. Mine is round.

I have a theory. We'll see if it pans out tomorrow. Somebody in the higher up Uhaul knows about the OilBurner site and said they had to find a way that the timing could not be easily advanced or any oilburner that rented one would be under the hood as it is pretty weak with a large load.

Because they were buying a bunch, Standadyne agreed to make a plate with non-slotted holes to keep the modifiers outta there. Heck, if I was working for Uhaul I'd probably have suggested the same!

Sorry but this now sounds more wife’s tale than truth.(Not suggesting you made this up, just thinking you just got bad info. Or trying to remember as you state the IP was replaced some time ago, you are now wanting to revisit and solve your issue.)

Talking about bitting off your nose to spite your face. The issue you are having is likely related to IP timing. As the IP and injectors wear the timing changes. Uhaul would have insured the truck was out of time by 40,000-50,000 miles. With no way to fix that.

Even if they replaced IP’s that failed with new ones it is not likely the truck would be timed. Standyne put alignment marks on these pumps. But after seeing dozens of pics on this site and a few in person, when timed I have never seen them perfectly lined up. Meaning their pumps don’t come timed. If you put a rebuild with a locked adjustment plate yours would likely be even more off.

Oil burners who have a timing meter also know moving the pump out of time does not make the NA motor faster, pull harder, or accelerate faster. So maybe a small few who did not know that would have bothered to try. But put these on thousands of trucks???? Turning up the fuel rate however does add power. If they wanted to solve a issue putting specialty bolts on the covers to the adjuster could have helped.

Also going forward please post accurate pictures. We want to help you but when you send pictures of something different than what you have. Also not stating it is not a pic of your actual part is not being considerate of the time we all are taking out of our busy day to solve your problem. So can you please send pics of your actual truck so we can see it? Then of the actual IP inside your truck so we can see how it mounts? A picture tells a 1,000 words as they say.

The reason I say this sounds like a wife’s tale is the only Uhauls I have seen with a IDI where the small box trucks on a Ford pickup or van platform. They used a IH/Navistar engine based on Ford’s requirements/specs.(Not someone else’s, Ford production truck, not a IH production truck) In all the reading I have done current and past I never saw it mentioned Uhaul’s IP was locked in position on the Ford platform and could not be timed. (By Uhaul or by special request of Uhaul via Ford.) I asked for a pic of the truck and IP as I do not proclaim to be a Uhaul historian. 1) I want to see if yours is based on a Ford platform. Maybe it was a larger International 30ft platform. 2) See it so it is documented here for future members to benefit from. 3) See this for my own curiosity.

To your point maybe Uhaul did this aftermarket at a large cost to them. But struggling how that cost was cheaper than retiming them every 30,000 miles to see if 6-20 fleet trucks were off time. Also what a blunder as the timing on a NA IDI is negligible. Where as turning up the pump would make some HP and potentially hurt the truck Long term.

If your hunch is correct I personally would put a different plate on the pump if easy or buy a different IP so I could time my engine. IDIBronco and I both regularly share how important correct timing on these IDI’s is.

Looking forward to seeing your truck and IP!

 

[hrsitton]

Oh man! Now I'm really ticked! (at myself) I've always relied on my excellent memory but at 80 YO it appears to be fading a bit.

I just went out to the truck to end this debate once and for all. I backed off the top nut on the stud as far as it would go along with the washer to take a picture of the ROUND hole. GULP? How did that slot get in there?

Thanks for everyone's persistence and especially patience.

So the plan is to first check for a cold exhaust port for a non-firing cylinder. If nothing, the timing will be retarded the width of a thin dime, (reminds me of using a strip off a Prince Albert can to set points on a Modle A), and see if that makes a positive change in start up smoke.

If not, I'm now debating if I want to turn the juice down as it actually ran really well for the 200 miles I have driven it since the IP replacement. The plan is to put it back into some actual service again.

Again, thanks to all.

 

[hrsitton]

Thinking.....it is sounding like no matter what, I should go to someone that has the proper equipment and get the engine properly timed. All I did with the installation was to line up the marks on the block and IP. The gear was left in the engine and not disturbed prior to the replaced IP. But from what has been said, the marks don't mean much if the truck is out of time in 40-50k miles.

 

[hrsitton]

I read an article by what seemed to be an experienced mechanic that said by ear even he could not get closer than 2 degrees. And I understand the forces on the rod bearings when the explosion takes place before its far enough off TDC to absorb more of the blow or force.

 

[Black dawg]

It is funny how the memory can work/not work.

If it has white smoked cold since the pump replacement, move the timing up a little bit and see if it improves. The timing on these engines isnt nearly as critical as it has been made out to be. There is a pretty wide window that they will perform acceptably in. From what I have found, anywhere from about 4 deg btdc to 9 deg tdc will work fine.

 

[Big Bart]

Thinking.....it is sounding like no matter what, I should go to someone that has the proper equipment and get the engine properly timed. All I did with the installation was to line up the marks on the block and IP. The gear was left in the engine and not disturbed prior to the replaced IP. But from what has been said, the marks don't mean much if the truck is out of time in 40-50k miles.

Well problem solved!

If you can find a mechanic with the timing equipment it would be your best bet. If they do not have a meter they are not likely to do more than you can advancing you pump a little at a time. It has proven difficult to find shops who still have the timing equipment for these old trucks. Maybe you buy one and do it yourself or buy one for your favorite diesel mechanic to borrow.

Yes the marks on the pump get you close so you can start the engine. However you need a timing meter from there.

As Black Dawg and others have found, trying different settings can make the truck run decent. But you won’t know how close to the 8.5* BTDC at 2,000rpm without the meter. At $200 for a meter, many pass on the cost and try by ear. To each there own, no judgment.

Your challenge is you have issues after installing a new pump. It is stated you should set timing after néw injectors or a new IP. Your issue could be from the timing being off, or fuel metering set too high, or both. (Possibly complicated from lots of sitting.) So without having your timing set correctly you may turn your pump down unnecessarily.

So I will let you choose the path forward from here.

 

[hrsitton]

Thanks. I'm still wiping egg. I've decided the path forward is:

1.Check exhaust port temps.

2. Then hopefully get the timing properly set. There is a guy not far from me that has been working on semi's, road graders, backhoes, you name it for several years. He will be my best bet. I'll update myself on meters and procedures so I can talk at least half way knowledgeable.

3. #2 satisfied, If I still not happy, I'll fiddle with the mixture.

Truck has been parked on the back burner but my hay hauler for my animals is belly up at the moment and the Uhaul is the easiest thing to get on the road. It's been a FunMover for 11+ years so it's inside are being gutted to make more room hay.

Thanks again for the persistant pounding on my thick skull.

I will for certain drop back for a report when all three are satisfied.

 

[hrsitton]

Ok. I just fired her and let it idle until close to operating temperature or there abouts.

Checking the block temperature at each exhaust location, the temps were running between 123 and 133F except one was at 99F.

Question: Assuming compression, valves and all are about the same, is that 99F enough to clearly indicate a leaky injector?

Tried to find temps on the net but no luck.

 

[Big Bart]

Hrsitton,

I am no expert on exhaust temps so take this all with a grain of salt.

I have read 3 posts where members took exhaust manifold temps to find a problem cylinder. The temperature trick work for them. So I would imagine the cylinder that is 99* is not up to par.

The challenge is why. It could be valves, rings, cylinder scoring, head gasket, injector, or loose injector line. (bleeds off pressure.)

Some thoughts on where to take this. If you have equipment or your buddy you mentioned does.

1) Check the injector line to they 99* cylinder to make sure it is not leaking or cracked.
2) Check the compression. If that cylinder has great compression you have ruled out a valve or ring issue. Harbor Freight has a set for around $90 as I recall that uses the glow plug hole. Some members had to cut some off the glow plug adaptor end to make sure it threaded all the way down. It will be obvious when you see it which end to shorten.
3) If you have an injector pop tester, test the offending injector and a couple others to see how far off the injector in the 99* cylinder is. Then hold the pressure at 500psi to see if it is leaking. You can find these for ~$90 or send the injectors out for testing for around ~$50.
4) If you come back with low compression in that cylinder, then you can do a leak down test to determine if it is the valves, rings, or perhaps the head gasket.

Also remember your not sure where your timing is set. So you still need to address that. I would not think it would cause a single cylinder to run cooler but maybe it can.

 

[hrsitton]

Thanks! I'm throwing out the possible injector problem for now. Took the truck on an 80 mile errand yesterday that brought the temps up a bit now running from 150 to 160. Thing is, the low 99F injector was up in the mid-range between 150 and 160.

Lots of black smoke under way so I'll go back to turning down the fuel a bit and see what happens. Tempted to do the timing at the same time but will resist doing two changes at a time.

I'm a little bit puzzled on the direction for a timing change. It was suggested that the automatic timing advance could be causing the excessive white smoke on startup and then to advance the static timing to reduce the smoke. Am I misunderstanding something?.

As the injectors and IP wear, which way does the timing change?

 

[TNBrett]

you can probably just start out by rotating the top of the pump towards the passenger side by the thickness of a dime or two. That should be a step in the right direction. It may get a little more clatter when cold , but shouldn’t once it’s warm.

 

[Big Bart]

HRsiiton,

I would do both as you having nothing to loose trying. You know currently your timing marks are aligned. So you can put it back where it is If changing it does not help.

1) Try moving the pump 2 dimes widths to the passenger side. Same amount of smoke or more, put the timing back. Less smoke, runs/idles better try one more dimes width to see if better or worse.
2) Then try turning down the fuel perhaps 2 flats. (Flats as in one side of a hexagon not complete turns.) If moving the IP did not improve things you can just line up the pump is marks again.

You know by changing out your IP odds are you are not timed. But you have no proof the rebuilder has the pump set too high. I say this because smoke issues can also be related to timing.

I would also guess if you had an injector issue, 99*, running it cleared it out. Also keep in mind many members have had good luck filling their fuel filter with ATF, letting the truck idle for a couple minutes and letting the ATF sit in the pump and injectors overnight. Not suggesting this will clear your smoke up, just perhaps clean out/unstick any parts that are problematic like a injector.