compression and leakage check is next on my list, I put toghether a gauge and am making a dummy injector tomarrow. should be able to tell if one cylinder is low on compresison or not. I am not sure what typical cranking compression on a 5.9 is but I should be able to see outliers. the snap-on gauge is 0-800 psi, I found a 0-1000 psi gauge laying around and made up a line with check valve and bleed-off. and as long as my dummy injector will seal I can just take out the check valve and run a leakage test with it aswell, that sould tell me rings, head gasket, or valves.
I thought about an oil analysis but havent gotten that far yet. If the compression test is inconclusive I will try running up to 2000 RPM no load and check exhaust manifold runner temps. then If I find a cold one try moving that injector. maybe they act different under pressure and heat, that a pop and pattern test wont show.

 

You obviously know what you are doing. If you can smell oil in the fuel the sample will have lots of flags alerting you what you already know. 5% is the cummins limit, which is quite a bit and a person won't smell it. Good luck and let us know what you come up with. cd

 

I am a a test engineer combined with a diesel mechanic and run emmisions test on diesel engines all day. although everything I deal with is infused with computers and sensors galor. steping back to the old 12v just makes diagnosis slightly more diffucult and have not dealt with the mechanical diesels much more than tinkering with my own. Slowly I am narrowing it down just thought there is a wealth of knowledge here and someone must have had similar occurances.

Thanks to everyone who gave me input, any more ideas are appreciated and when I figure it out I will let everyone know.

honestly I like the simplicity of the 12v and would much rather deal with them more, but times and technologies are bound to change.

 

does anyone have a factory cummins manual that outlines acceptable compression values?

 

Anything over 400 is good. You should see around 430 +/-

 

I'm sure your problem doesn't have anything to do with compression. . . save yourself the time. If you are truly getting diesel in your oil most likely it is coming from the injection pump, since it's the only place in the engine where you have fuel and lube oil circulating through in close proximity. As I understand it there's some seal in there that if it goes bad it can leak fuel into the oil inside the pump then the crankcase.

A pump problem could be causing poor atomization too, causing the stinky white smoke.

Here's another thing you can do to rule out air in the line. . . put a longer hose on your fuel drain valve and stick in into a clear 2-liter soda bottle. Start truck, let it idle, then open up the drain valve part way while it's running. When the bottle is like half full (make sure hose goes to the bottom) watch for bubbling or foam coming out of the drain hose. If there is you're sucking air somewhere.

Vaughn

 

I dug out my B series service manual for ya....here are the troubleshooting steps for you......follow in order

Excessive white somke

1 coolant temp too low

2 air temp too low

3 poor fuel quality

4 injector pump timing incorrect

5 injectors malfunctioning

6 injector pump malfunctioning


Lubricating oil contaminated -- Fuel in oil

1 engine operating too cold

2 lift pump seal leaking

3 injector needle valves not seating

4 injector pump malfunctioning

Hope this helps you out

 

thanks guys, I was hoping to rule out compression, although thats what the experts at a local pump shop and PDR concluded after I told them about the tests and checks I already did. I thought the volume of fuel squirted out from the injector lines was low when they were cracked indicating some problem with the pump but I wasent sure. While I have it all apart and already made an adaptor and guage setup I may as well check compression to know where I am at. will update of any progress

 

What happened ?

 

Well I haven't had much time to work on it, Been busy on my house. Im almost posative it is an injection pump problem and am trying to find a reasonable place to bench test it two places I called have been 350+. has anyone herd much about the pensicola diesel reman pumps? because for twice the price of the bench test I could have a rebuilt one.

Ill get back when I have news

 

The #10 post asked about the engine temperature. If it never warms up you could be pushing fuel past the rings. The warmer it runs the better the mileage

 

It runs the same temp it always has, normal operating temp. fluctuates alittle but it has always done that. I should have the compression test done in a week or so and then I will know alittle more. still thinking IP.

 

Well I finally got time to do a compression test and the # 1 cyl. is low, #'s 2-6 are 380-400 and # 1 is 260. so I think I found my problem, although now when I rebuild it I need to figure out why it wore the rings out in that cylinder. i did re check it and got the same 260-270 psi and then with oil added bumped to around 300.

 

Wash down?? Leaking injector??

 

Partially plugged piston cooling oil nozzle?