View Full Version : A new source of oil production.....
My 2002 GMC Duramax/Allison has gone into the oil business. We changed the oil about a month ago and I told a new employee that it would take about 7-8 quarts to fill the motor after a filter change. I noticed the exhaust had a strange smell to it about a week ago, but couldn't figure out what it might be. Today I noticed that the oil pressure was at about 20-25 psi when it normally idles at 40 and runs at about 60-70 psi. I thought I was low on oil and stopped to check and add some Delo 400 to it. It turned out that it wasn't low. At first it didn't register as to the fact that it was actually high. This morning I decided to drain the oil and change the filter just to be sure. After draining out 7-8 GALLONS, I knew something was wrong. I thought at first that the new hire had heard me say "gallons" and not "quarts." We changed the filter and then the used oil which wasn't very old. It turns out that the oil was very diluted. I believe this to be a case of injector bleed-down, but I'm not certain yet. The motor has 255,500 miles on it and still runs very well. I replaced the filter and refilled the crankcase today. I'll keep an eye on this to see if it is still gaining. I may have to redo the injectors, but in the meantime I'm going to see if I can hook up with a Saudi prince for some pointers in getting into the oil industry.
Has anyone else had this happen? Is it a case of bad injectors? Is it time to just change the injectors or should I do the heads at the same time. When would it be a good idea to start thinking about the bottom-end? I would appreciate any ideas at all on this. Thanks for your thoughts. Mark!
Mark Rinker
10-31-2011, 20:23
Okay, first things first. Somebody chime in here if I am wrong, but if memory serves (and it rarely does) a Duramax requires ~10qts for a complete oil and filter service.
Secondly it is almost a certainty that your source of dilution is in fact an injector or three that have gone bad. The good news? Replace the injectors, and get ready to enjoy another few hundred thousand miles. :D
While you are in there, replace the injector lines, water pump, thermostats, glow plugs and harness, and you might inspect radiator and intercooler hoses for replacement at those years and miles.
Happy motoring, Mark.
DmaxMaverick
10-31-2011, 20:51
Mark is right, on all counts. The crankcase should fill at 10 quarts, and it's time for injectors. Don't wait for the episode to repeat. It's gonna keep making oil, and the Saudis don't want to talk to you about it.
I got a quote from my local buddy that is the parts manager for the dealership where I bought my crewcab originally. His price for the entire package of everything that I need to R&R the injectors was $2,100.00. This was with 8 Isuzu remanufactured injectors at $245.00 each. The second best price I could find in Portland was from the people that do all of my other pump and injection work and they had the remanufactured injectors at $310.00 each. My local diesel shop has quoted me $750.00 for the labor on the injector R&R. It looks pretty good to me other than I now need to create additional reality around the concept of cash flow.
Add 8 new high pressure supply lines.
Heartbeat Hauler
11-05-2011, 10:34
I got a quote from my local buddy that is the parts manager for the dealership where I bought my crewcab originally. His price for the entire package of everything that I need to R&R the injectors was $2,100.00. This was with 8 Isuzu remanufactured injectors at $245.00 each. The second best price I could find in Portland was from the people that do all of my other pump and injection work and they had the remanufactured injectors at $310.00 each. My local diesel shop has quoted me $750.00 for the labor on the injector R&R. It looks pretty good to me other than I now need to create additional reality around the concept of cash flow.
Can you clarify this as I thought Bosch is the only manufacturer of injectors for this engine. And, all remans are not created equal. Some of the known "good" remans are either from bosch dealers or LDS. I have found these injectors as low as $225 each after core return. As others have said swap the injector lines too as there can be corrosion in them that can lead to premature failure of your new (remaned) injectors.
I was speaking with my buddy who is the parts manager at the local GMC dealership and he said that the injectors they have through GM are remanufactured by Isuzu. All I know is what I've been told. Given the conversations here, I will give Harold another call and clarify some things.
DickWells
11-06-2011, 10:36
This injector mfg. business, for the DM injectors is becoming more and more interesting as time goes by, and our engines, (especially the LB7's) get older. Mine is on it's third set, now, with about 20 K miles on them, and I've done about all I can do to extend the life expectancy, but I still expect to have to replace them again at some point, if, God willing I'm able to continue to tow my home all over the continent. I'd truly love to know of the existance of a "real" injector with a "real" life expectancy of more than the 80 K miles, or so, that the LB7's have given us.
I've done too many up-grades and one-off mods to my Sierra, to even want to consider swapping trucks, so I'm looking at doing whatever I need to in order to stay mobile with what I have. Besides, I don't want to go much "newer" anyway, what with pee-pee in the tank, and ever-increasing complexity with our diesels.:D Just give me a better injector for my next re-build. Please!
My 2002 Duramax is at 256,000 miles with a Van Aaken boost module and I am still on the original set of injectors. I've replaced the water pump once and the transmission control module twice. I'd say that's a pretty good track record given the speeds I travel and the loads I haul and pull. I will track down the source of the injectors that my GMC dealer is proposing.
DickWells
11-06-2011, 20:43
That's great mileage for any LB7! My first replacement set went in at 86K miles. That was done up in Longview, WA, back in 07, at the GMC dealer, and the cost was - not a single penny. The next, was in 010 at 121K in S. NY, at a cost of $4K+! A free-lancer did it, because the local dealer wanted an estimated $6400! Warantee issues have been given a much different approach by GM since the economy went belly-up. I was within my seven years and 200K miles, but, no help was forth-coming.:mad: No amount of talking to GM reps would get me any consideration. I ranted and raved, and spouted off about never buying another GM product, (more because of the buy-out, than the warantee thing), then went through a lengthy cooling-off period, where I finally calmed down, and reminded myself just how much I like this truck.:) Now, I'm back to the way I described in my first post; gonna do whatever I need to, to stay mobile with the equipement that I have.
Good luck with your job of stopping the "making oil" thing.
Mark Rinker
11-07-2011, 10:06
My 2002 Duramax is at 256,000 miles with a Van Aaken boost module and I am still on the original set of injectors. I've replaced the water pump once and the transmission control module twice. I'd say that's a pretty good track record given the speeds I travel and the loads I haul and pull. I will track down the source of the injectors that my GMC dealer is proposing.
That is nothing short of amazing results for an LB7...my 2002 went to 175K before the first replacement set, and was showing signs of the next set smoking at 285K...
Where do you buy your fuel - same place or anywhere you find it?
Do you have additional filtration, or just stock filter? How often is it changed?
Any additives used? What and how often?
Who knows, maybe the additional fuel rail pressure the Van Aaken box provides helped the injector life??? :confused::confused::confused:
Heartbeat Hauler
11-07-2011, 12:59
That is nothing short of amazing results for an LB7...my 2002 went to 175K before the first replacement set, and was showing signs of the next set smoking at 285K...
Where do you buy your fuel - same place or anywhere you find it?
Do you have additional filtration, or just stock filter? How often is it changed?
Any additives used? What and how often?Who knows, maybe the additional fuel rail pressure the Van Aaken box provides helped the injector life??? :confused::confused::confused:
I think that guys have figured out that maintaining positive fuel pressure to the pump does more for injector life than anything else. Many have added lift pumps to maintain that extra few pounds of positive pressure to the pump and accordingly to the injectors. The fuel is what lubricates the injectors and if there is sporadic pulses of fuel due to leaks, clogs, weak CP3 pump you will get pockets of air or a no-fuel condition, which means no lube to injectors and at 20,000+ psi is death to injectors. I have run Stanadyne Performance Formula with 20% bio (bio being one of the best lubricant for injector systems) for the first 8 years of my truck's life. I also added the Racor Secondary fuel filter (Pre-OEM) for additonal filtration a year after I bought the truck new. Like an idiot or cheap bastage or both, I did not opt for the lift pump with the secondary filter setup. I moved to WV about 2 years ago...no bio...I have started adding Stanadyne Lubricity formula with the Performance Formula. Well, now at a mere 94,000 miles my truck is surging like a bronco bull on steriods and smokes like the 9:15 train out of Chicago..:( I go this wednesday to find out what the result will be. No doubt all injectors and lines....bummer.
So, that was the long way around the barn to say that I think that you are right Mark about the injectors benefiting greatly from a lift pump (positive fuel pressure) more so than the additives and the extra filtration, although I would do ALL three, and I will in the future.
There's really 4 things that are working against our injectors:
1) Air
2) Water
3) Dirt
4) lubricity (lack of)
A lift pump while primarily focusing on #1 (air) can help with pretty much all of the above.
Years ago an old time log trucker lived down the road from me. Every time he fueled up he poured a quart of ATF in the tank. I hadn't been back to that town in over 25 years and had a chance to go through one day last summer when they were having a parade. Well, Al is now pushing up the daisies, but his son Allan is still driving his dad's KW with BC400 in it. It is the same original engine with one in-frame overhaul on it in all these years.
I have been using ATF in my 6.2's. 6.5's and Duramax all these years and Al's suggestion. In the last four years I switched a bit and have been running 1/2 ATF and 1/2 Lucas Diesel Conditioner. I have always had very, very good luck with my pumps and injectors and the ATF may have been the reason for the good lifespans. I know I'll keep on using it too.
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions Inc. All rights reserved.