Blue Smoke

[TOM]

Our 60hp BMC has been blowing a bit of blue smoke and uses a bit of oil but otherwise runs well,starts first time so compression is good.The mechanic has told us that it will last long enough to get us around the world approx 4 years but recommended that we get the injectors serviced which have not been done since rebuild 2600 hrs.
Mechanic just called to say that under testing 2 of the 4 injectors are not delivering the correct fuel at revs and that there has been evidence of some water in the system at some time.By replacing the nozzles he thinks that it may stop some of the smoke and improve overall performance.
The mechanic comes highly recomended and seems like a nice guy but iam a bit out of my depth here .Can any one tell me if they had similar problem with smoke and what you did.I do not want to take the motor out to have the rings done and the mechanic says it is not neccesary.
Guess the question iam asking is could the motor last another 4 years say 1600 hours.?

[Chief Engineer]

Blue smoke is oil.

I don't think injectors will cure that.

It is possible that too much unburned diesel could have washed th cylinder walls.

Don't assume compression is good because engine starts.

Have a compression test/leakdown test done.

[BlueWaterSail]

Replace the 2 malfunctioning injectors and see if that helps. Do the compression test as Chief suggested. The key to longevity is proper maintenance - the fewer the uncertainties, the lower the risk of a failure.

BWS

[Rhosyn Mor]

TOm,
the Perkins on Rhosyn Mor has essentially the same problem, engine is running sweetly, starts first time every time. but a fair bit of blue smoke coming out of the exhaust. I replaced the injectors.I have had a couple of people look at it, and the general consesus is; there might be water/oil in some of the hoses, and its probably time for a valve job. THe mechanic said that as long as the motor has clean oil , clean fuel and clean air he would recommend not messing about with it too much, it is running very nicely other than the smoke.

[Cheechako]

I had a perkins that made no smoke. I had the injectors replaced and then the engine smoked for quite a while, more whitish smoke though, but seemed a little blue. How confident are you that it is really blue smoke?

[Chief Engineer]

The other thing you can do is cup your hand...pass it thru the exhaust and sniff.

There is a distinct difference between oil, diesel and antifreeze smoke Blue/Black/White

[speciald@ocens.]

Sounds like rings are leaking. Check compression.

[Robertcateran]

Sounds to me like a bit of a glazed bore. Fix the injectors and drive it hard for a while and see how it comes out,
regards,
Robert

[TOM]

Thanks for all your replies .Pretty sure it is glazing as engine is using a bit of oil. I have not been running it over 2000rpm so when the injectors come back i will run it a bit harder perhaps it may clear up a bit.

[GordMay]

See also a very old discussion:
“The Smoking Gun “
Interpreting Diesel Exhaust Smoke:
➥ http://www.cruisersforum.com/forums/...-gun-1707.html