fuel in oil???

[chessy56]

On a 2001 LB7 Dmax- if you start getting diesel fuel in the oil, can you smell it? My injectors were last replaced at 175K miles; the smoke at idle was heavy and quite noticeable. I currently have 268K miles on the truck and I'm beginning to see what appears to be a "slight trace" of smoke at idle (not smoking anywheres as near as heavily as it was when I last had them replaced). Trying to identify an increase on the dip (stick) is not quite easily done, since GM went away from the dip stick and used a cable with an indicator slug at the end. Since the last injector replacement, I've been using either Power Service (Silver jug) or Lucas fuel treatment (yeah, not the most popular according to some, but better than nothing). I put ~600 on the truck weekly.

I guess my other option is to pay someone a few bucks to read the injector rates. And what about this "paper test" that is supposed to indicate the presence of fuel in the oil? Anyone?
Thanks.

[More Power]

White smoke at idle can be due to poor atomization or leakage at an injector nozzle - not necessarily because a fuel in oil problem. But, if that's the case, it should show up in the injector fuel rate balance.

Put a drop or two of oil (off the dipstick) onto a white paper towel. As the story goes, if there's fuel in oil, two concentric rings should appear when fuel is in the oil. The fuel will wick farther-faster into the paper towel. There should be many posts and threads that can be found here in this bulletin board using a keyword search about this topic.

Jim

[chessy56]

I did the white paper towel test and didn't see anything. I did collect a sample of the oil during my most recent oil change and sent it in for testing- we'll see if the lab reports any fuel getting into the oil. I checked the balance rates with both a Tech II monitor as well as a Edge CTS. Generally, they are:

Cyl 1: -0.6 (in gear), -1.2 (park)
Cyl 2:-0.7, -0.9
Cyl 3: 0.1, 0.3
Cyl 4: 1.7, 2.0
Cyl 5: 1.9, 1.3
Cyl 6: 1.3, 1.5
Cyl 7: -3.8, -4.0
Cyl 8: -0.3, 0.4

Looks to me like Cyl 7 is suspect, with Cyl 4 next in line. It's not smoking anywhere near as heavy as I've seen it before, but the sight of any smoke gives me pause. My guess is that another set of injectors is in my future, but "when" is the question. Cyl 7 varies if I watch it long enough-- from -2.8 to -3.8 after a good long run. When I do see smoke, it is very light, but the smell is definitely heavier than what I'd consider "normal".