Just like the title- what is a way to tell if your injector o rings are bad or going bad. Looking for a low tech answer and also wondering how to use AE to diagnose this. On another note. Last spring I had a CCT done and ended up replacing #6 injector. (Truck was smoking badly) it has run fine since, no problem. Now that I have AE, I ran my own CCT for fun. #6 pops up still. Is this something I need to clear somehow? How do I get some kind of reading to compare against the other injectors? Should I even worry about it since it runs as good or better than when I got it? My UVCH looked a little loose so I did the .50 cent mod to tighten it up. Could this possibly cause AE to give that readings? Haven't had a chance to rerun the CCT yet, but hopefully tomorrow night I'll have time. Thanks!

 

Generally injector orings are evidenced by a black fuel filter...

for your #6 what are the PERDELS?

Do you have any blowby, evidenced by pressure at the oil fill cap?

 

Don't worry too much about the contribution test unless you have a reason to run it. AE can watch the live data. I just don't remember what they call it, but you go to the live data tab and select each cylinder in a separate boxes. Engine needs to be warmed up for this. A reading below 5 is what you want. 0 is perfect.

To diagnose o-rings, watch icp pressure in IPR duty cycle at idle and under load. Also check for oil use and an oil stained fuel filter.

 

I agree with Chris. ICP drops while IPR% goes up.

Also, like BigAl said, a black fuel filter.

Another symptom is hard starting when hot.

 

Why do you suspect your injector O-rings (beyond a single AE test with an "off" number)? O-rings are tough to "prove", but a high IPR reading (above 40% at WOT) is common.

 

2 years ago when I had this engine out, I did everything wrong. Used Permatex instead of Internationals 'Supergoop', had a swollen glo plug, had to pull a cylinder head off, and still replaced them with autolites(ignorance), pulled the engine immediately back out 2x due to a 'rear main oil seal' and finally, 2 weeks later got it to run again. Well, over time I've been taking remedial action. Super goop was fixed the last time I pulled the engine, just pulled out the autolites yesterday, etc. The thing that concerns me about my o rings is that when I pulled those 4 injectors to get that glo plug out, I used the same o rings.

 

Ah... set of 8 (including new copper washers) at riffraff diesel [LINK]. Don't mess around, just do them. Failed O-ring or and/or copper washer can cause all forms of nastiness - I have experience with that.

Make sure you put the copper washer on the correct way, and that it sticks to the nozzle before inserting. Don't use metal tools when working with the O-rings, you can mar a surface... and 3000 PSI of oil will find the smallest leak to utilize.

 

Ok. I was originally thinking the same thing, but my filters have been clean, so I was having 2nd thoughts. I'm assuming those kits come with the little copper washer? It shows a picture in the install directions, but doesn't specifically say they are included...

 

Copper washers included. I didn't know that the first time I ordered, so I bought 8 of them. I now have 8 spare copper washers.

 

So certainly replace the copper washers if you have them. Having said that, I have reused the coppers three of the 7 times I pulled my sticks in the last year - I didn't plan well enough in advance to replace them those times, but I'm thinking it's not such a big deal, since it appears to me that the injector seats against the copper washer each time, and torquing applies the same pressure to the washer, causing it to reform the seal. It's not like the injector bottoms out on some other shoulder, like say a toilet and wax ring. The washer should work again a few times, similar to the copper washer on your oil drain plug.

This last time I pulled the sticks, I reused the orings and copper washers, and it appears to be working fine. Granted the orings are only a few months old, and this is the first time these particular copper washers have been reseated.

Pulling sticks regularly is not the norm, of course, so this situation should not occur typically.

 

My thoughts on this: If you pulled sticks that have been in there for a long time and re-installed them with the old O-rings, this could cause issues. If your O-rings are reasonable fresh, discretion is involved... but O-rings are cheap and I just don't take the chance myself.

 

I I’m using about 6 quarts of oil in 200 miles did the oil cap blow by test the Stays put pull the fuel filter no oil in fuel bowl dear new injectors last May started doing this in October any advice or in what direction to go do I need injector O-rings or does it need to be overhauled

 

6 qts in 200 miles you should be smoking out the whole street when you drive, if it is in fact burning oil because of bad piston rings. Have you checked the PCV? If it's stuck open, you could be sucking oil through there. You should also see signs of that in the intercooler boots.

 

How is the fuel mileage recently? If you are getting great MPGs it's because the oil is flowing past the o rings into the fuel and back to the tank.

Don't even worry about a rebuild, blow by is good.