If you can't find the smoking gun look for the vultures to start circling. Wait, different question, bad pun.

Run a compression check, there is already a thread.

GM makes a top end cleaner that has been known to free stuck rings in rare instances. It is cheap and may be worth a try if you take your injectors out for another reason.

A leak down test is probably better than a compression check.

both are valuable, no doubt. Out of all the vehicles I've ever bought, I've never compression tested one of them. Not that I didn't want to, but I check everything myself, and I wouldn't feel right asking a seller if I could jump into his engine and pull stuff off to compression/leak test it. Nor would I allow someone buying a car from me to do the same. Bring it to an established mechanic and pay them if someone really cares, usually people care more about how clean the glass is.

I WOULD, however, ask if I could unhook the breather hose and put the bag on it. It literally takes seconds and no tools and I bet most sellers would agree to that. If there were some known comparative values, which is what I'd like to establish, then someone could try the test and say "Gee, I looked at a sweet looking wagon. Started OK, and filled the bag in 15 seconds. Car has no rust and the price is right, should I buy it?" One could be advised that this might be OK for around town use in Florida, but not a regular highway commuter in Minn.

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'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

Now would that be Hefty brand or store brand bags?

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Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
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Section 609 MVAC Certified
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"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

what you need is a slack tube manometer. test off blow by tube, you can make one for less then $10 or buy one homemade versions can be found in a web search, either work fine
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7506600348

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74 240D rolling restoration, daily driver
ASE Master Truck Technician
I enjoy my work so much I had to buy a diesel to play with !

well, you certainly could use a manometer to check the crankcase pressure, and that would be useful too. All you need is a piece of clear plastic tubing, attach to pressure source, loop it into a "U" shape and pour a few inches of water in. The difference in water levels from 1 side to the other is the pressure differential. About 27.7" water=1 psi. However, I think that a better indicator of cylinder blowby can be had by measuring FLOW rather than PRESSURE. My engine for example, generates relatively low blowby FLOW, (I believe), yet can generate relatively high PRESSURE, as the valve cover, crank seals, oil pan seals, etc. are really tight, perhaps as evidenced in the last picture I posted here which shows the bag connected to the crankcase still pressurized 20 minutes after engine shutdown. An older, leaky engine with a lot of blowby will generate much higher FLOW and pressure be a function of both cylinder blowby and seal condition.

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

Well, anyone willing to give this a try? For those of you going to the NE GTG, you could do sort of a "reverse race" to see who has the most hot air! I'm homebound this weekend....Ahh, I couldah been a contendah!

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.