Injector Life Expectancy Question

[Jeff H]

I have 155,000 miles on the truck now. There is also alot of idle time that should be added. My question is when do the injectors start to lose there performance?

Right now I do have a slight miss. I can feel it pretty good from idle up too about 1300 rpm. Its not to noticeable rpms above that. But can tell that its not as smooth as it should be. When it starts on a cold start the rpm is vary low till it warms up a little. There is heavy blue smoke at start up too. My mileage is down. The pep is not just not there when I step on it.

All the started early this spring. I checked lift pump pressure thats plenty good. I did valves. Cleaned prescreen fuel heater.

Only thing I can blame it on is I mixed clean motor oil in the fuel. Wonder if it may have gotten too thick or gobbed up going into the injection pump and injectors. Thats about the same time she lost it performance. I want to get it back the way it was before winter. Could use some advise. Thanks Jeff.

 

[Grey Wolf]

If you would like to see what you injectors are doing pull them out and take them to an injector shop and have them pop ‘em. You probably have lost your fine misting spray and have a dribbling injector or two. If you follow this link you can find a shop by you. There is also some good information in there if you wander around!



First go to member services, then member directory, then make your member selection which I would assume is U. S. Members





http://www.diesel.org/

 

[illflem]

Jeff, I pull the injectors on my JD tractors every 5000 hours, equal to 250k miles, and have them checked and cleaned. JD dealer charges $8 per injector plus parts if they need rebuilding, so far I have never needed parts, one set of injectors has over 17,000 hours (850K miles) on them. JD dealer has told me I am wasting my time and money unless I have excessive smoke on startup or running but I do it anyways. I assume Cummins injectors are much the same. I think your missing could be due to a sticking injector pump plunger, try using fuel additive with lubricity and see if it clears up. I like Howe's.

 

[Joe G.]

Jeff,



Adding ANYTHING other than properly formulated fuel additive can mess up the works! There was a thread a short time ago that got into the details. My '95 has over 172K miles on it and runs great. Once in a great while I will add some Cummins fuel additive in an effort to keep my injectors clean. That may be a waste of effort. Maybe if my small stock injectors give me trouble one of these days I can justify replaceing them with some larger ones from a 215 HP.

 

[Ray Torresdal]

injector life

I've been helping a friend lately, driving his N14 Cummins, 430 Hp. , occaisionally. It has 625,000 miles and hasn't had an injector out yet. It pops right off when you hit the key, and runs pretty hard with your foot in it. Ray

 

[BCFAST]

injectors

The injectors should last near 1 million miles... try dumping in some Stanadyne.

 

[Power Wagon]

I would never DREAM of running those injectors past 250K miles.



At your milage, if you suspect they are causing rough running, take them to a pump shop and let them pop test them. Most likely, that's not the problem, but don't be surprised if they find the popoff pressure is low and the nozzles don't atomize like new ones. A big cloud of spray is NOT correct. Good injectors appear to squirt in narrow streams.



They are NOT good for a million miles. They are subjected to the most intense heat, pressure, and high-pressure fuel flow through small holes - they erode.



Illflem, your deere dealer did you a disservice. You really can't tell how good or bad they are by a pump on the nozzle tester. 5000 hours is more than enough time. They needed new nozzle tips then or not long after. A lot of Allis Chalmers could not get to 3000 hours before they were washing the cylinder walls down. But the Bosch injectors in the Deere were better.