Archived Injector problems in Central Mexico

[TPringle]

TDR, I have a 1992 W250 truck that I use to pull trailers in and out of Mexico. The fuel economy was way down, as the power, smoke up. I had replaced all the filters and verified the lift pump was working before the last trip. No change. I removed the stock injectors to have them checked and cleaned while here in Mexico. They have about 100k miles on them.



Now I have 2 that leak diesel (I think from where they screw together). I removed the 2 leakers and had them checked again. They still leak, but not as bad. I have pulled the 2 trouble inectors a 3rd time and am going to try to have them checked & repaired again. They leak worse when the engine is warm, and the power doesnt seem right. The idle speed is way down when I have it in gear (automatic).



I feel I made a mistake in doing this. I have no experiance with the Cummins injectors, and wonder if this is something I can take care of, or if I can run this truck out of Mexico to where I can get some rebuilt injectors. I just dont want it to lay down on me while crawling over a mountain. It is a 600 mile trip, and I will be loaded. I need to make 2 trips, and soon. I am pretty well dead where I sit if these injectors still leak after this time. Any suggestions?

 

[sweeda]

Don't take this wrong but some times we jump to fast with out statrting in the beginnig . I myself am Guilty of this. did you check the the boots between the turbo and the intake. not sure on a 92 but if inter-cooled check it. Just my 2 cents.

It's a place to start. Good Luck!

 

[TPringle]

Actually, I did check the connections, even took the intercooler out and washed out the radiator, and all the coolers. Everything seemed tight & intact. I dont have any boost gauge, so I really dont know how things are working. Probably ought to add that to my "to do" list.



I guess I am asking more than anything if a couple injectors are leaking a little, if I am in danger of a breakdown if I try to drive it out of Mexico. I have been broke down more than once in this country, and it isnt pleasant.

 

[HBarlow]

I have no experience with or knowledge of 12 valve engines so can't help much.

It is not clear to me from your posts whether you have two injectors leaking externally or internally into the combustion chamber. If leaking externally I'd probably fire it up and return to civilization asap hoping not to start an engine compartment fire. If leaking internally into the combustion chamber you could potentially damage or destroy an engine.

I agree that you probably made a mistake in having a mechanic who may be capable of removing and reinstalling injectors test and repair them. He probably doesn't have the equipment or training to actually repair injectors.

Worst case, if you fear damage to the engine by running it with leaking injectors I'd suggest contacting the company in San Antonio, "Diesel Injection Service" or a name similar to that. Other TDR members can provide the proper name if I missed it. You might be able to leave your truck for a few days to travel to SA to obtain replacement injectors or have a set shipped? I have never been down into the interior of MX and don't know if mail or delivery service is reliable.

 

[TPringle]

The injectors are leaking outside. It was a reputable firm that did the cleaning (I am doing all the mechanical hands on). But, I KNOW the 1st time they abused them, and had to file off 'boogers'. I returned them today and they checked them, and told me I need to put teflon on the threads of the return line bolts. I am going to try it. The fuel is coming up from inside the hold down nut. I am getting to where I can pull those and install them blindfolded!



I will come into McAllen, Tx and wouldnt be too far out of my way to go into San Antonio. Any suggestions on what brand or type? Everything is stock on this truck exc the exhaust. I have heard mention of POD or 370 or some kind of injector like that. I want something to keep the economy up. The reason I pulled the injectors is because the economy had dropped from low 20's to around 12-13.

 

[Missouri Mule]

Don't know about the POD but the Bosc 370 hp injectors are way to big for your engine/injector pump.

You mite get away with 175 hp or 180 hp injectors but you will have turn up the fuel screw and if you turn up the fuel and/or bilgger injectors a boost/Exhaust temp gauge are needed.

 

[PToombs]

Don't put anything on the return bolts! The copper seals should work. if they don't, get a propane or other torch, heat them, and drop them right into cold water. This will make them soft again. Sealer, liquid or tape, will get into your fuel system and cause big problems.



POD's and 370's will be too much fuel for your stock truck. A set of 190's, if they have them, will be better for mileage and power. They have more, smaller holes which atomize better, resulting in a better burn.

This may not fix the original problem, but it will fix the injector problem. I hope they are the same problem.

Good luck!

 

[TPringle]

I think I have found the problem, now the solution - uhhh. I am down to one leaking injector, and found the "rebuilder" had damaged the face where the return line goes on. I havent used any tape, did try a little permatex #3, but that disloved once the fuel hit. I tried cleaning the the injector where it was damaged (what have I got to lose?) with a file (think I may had rounded it). Still leaked. I took it out again, and carefully polished it with fine sandpaper over a piece of glass. Still leaks. I fear if I tighten the return line bolt much more that I may break it or strip it (or the injector).



Originally the injector was leaking where the 2 halfs went together, but I suspect it was also leaking on the return line, just didnt know it.



I am going to try the propane torch trick if I cant find washers here. If that doesnt do it, I had thought about a temp of using rubber washers. Is there any pressure on the return side?

 

[PToombs]

Rubber washer will work, if it's thin enough. There is very little if any pressure on the return, it only goes back to tank.

Good luck, hope you make it out!

 

[TPringle]

I "think" I have the problem under control. I still need to do some more road testing to be sure. I couldnt find any copper/brass washers. I bet they are down here if I knew where to look. What I did to 'fix' the problem was to apply a coat of solder on the injector side of the washer, then took my time to smooth it with a file, then fine sandpaper. I tightened it "slightly" beyond where I really felt comfortable, after testing it once - still leaking. As of now, if it is leaking, it is really a small leak. I will road test it some over the next few days, and check back in with results. I did throw in some rubber O-rings just in case. Thanks for the input all!

 

[JR2]

I once used a couple of round wire terminals and just cut the crimp portion off. It worked like a champ... that same night we also made a replacement banjo bolt for the return line. Sounds like you are quite handy at repairs, good luck.

 

[TPringle]

Seems my repair is holding. I have made several hard runs over the expressway, and I dont see any fuel leaking. It seems like it may be a little "damp", but maybe left over from the previous leaking. I think it will make the trip out. It still idles lower than it used to, not sure what to make of that but does smoke less. I think the immediate crisis is over. Thanks all who gave help!

 

[TPringle]

Guys, I made it! I drove the 600 miles from central Mexico to the border with a 32ft trailer loaded to the gills! The damaged injector started leaking on the way, but seemed like very little, so I kept 'er running. I have the truck down at the campground in McAllen, and the injectors in the shop. I am investigating the 190hp tips. Idle speed still seems pretty low, esp when warm. Thought you might like to know. Got another trip back in this weekend and another trailer to tow out.

 

[Missouri Mule]

Gald you made it!

 

[TPringle]

WOW I got my injectors back today from the shop, $800 later, but MAN, did they wake that truck up! It has flat come to life! I think the performance had been deteriorating for a long time, but so slowly that I really didnt take note until it was about dead. That engine starts, idles and acelerates so much more smoothly it feels like a new truck! It is also quieter, it had really been "rattling", even before I pulled the injectors in Mexico. Yes, it still rattles, but is much more uniform and even than before. I think my 'interest' in this truck is starting to come back. I will be going into Mexico tomorrow, and am eager to see if I have any improvement in fuel economy. I had been struggling to get 250 (300 tops) miles from a tank of fuel. I will also post this in the 1st gen forum, and continue to update as things progress. I guess it aint dead afterall!Oo. Thanks for the advice all!

 

[WoodChuck]

Well that's good news. Have you done anything to the exhaust housing on the turbo? There might be some performance and mileage gains to be had there too.