View Full Version : Yanmar turbo blue smoke

L.A. Cook
08-09-2003, 07:53 PM
" I have 87' Yanmar, 66hp, turbo. Major overhaul, fuel injection pump, turbo seals, rings, injectors, etc. No oil from crankcase vent pipe evident but still smokes. Much blue on startup, blue -grey after warm-up. Replaced thermostat (80C) to 100C. SOS.
Lee @leecook1941, Yahoo.com "

08-11-2003, 08:07 AM
How many hours on this engine and did they do valves when overhauled. Oil on start up sounds like valve seals leaking after shutdown. Just a guess. try some Marvel Mystery Oil for top end conditioning. Kim

Lee Cook
08-11-2003, 02:45 PM
" 87' Yanmar, 66 turbo, blue smoke - MORE to say.

See earlier comments.

Paid for new valve guides, engine has 200 hours since overhaul, turbo seal replaced at overhaul, again after 150 hours- told it was leaking.

Appear to use little oil - difficult to determine with dipstick - shows at line but oil pressure on lower edge of green line.

Five diesel "experts" and still no answer. Baffled and frustrated, $16K CDN spent thus far. "

08-11-2003, 09:49 PM
" Have you tried your local Yanmar dealer. This may be a specific problem for this certain engine and maybe he has had this problem before. If it is using hardly any oil, why not suck it up and add oil instead of chasing a little blue smoke and wasting more $. I agree it would be nice to be perfect, but at what cost? It sure sounds as if something is dripping oil into the cylinders after shutdown and then major smoke at start up. Got me guessing but I still go with the valve seals. Good luck and post results, Kim "

12-02-2005, 11:10 PM
"If all was done and you broke it in right, to seat the rings. The rings may not have seated, does it start well, like right away? It should. As Kim says check those Valve Stem Seals. Did you get the turbo checked and bench tested? Turbo could be leaking between boost and exhaust turbines. You have a 4JH-TE What is this engine turning up to in gear and full throttle?"

whitney jackson
04-05-2008, 03:14 PM
what can cause a turbo failure on a 420hp yanmar model 6ly2m-ste.

10-13-2009, 09:48 PM
"I have a Yanmar turbodiesel 4JH 100 horse turbo diesel with 42 hours. It is 6 years old because the engine was purchased and the boat built around the engine(basically). Now, when the engine starts up, there are clouds and clouds of blue smoke, can anyone advise? Thanks, I am new to all this, B"

10-14-2009, 05:29 AM
"have you the right oil?new oil filter and right level,is engine set up according to yanmar specs with regard to engine slope from front to rear good luck,oh could be glazed clyinders???but check the cheap things first,eg make one change at a time otherwise you end up chasing your tail cheers kiwi guy"

10-14-2009, 08:01 AM
"You know, I have given up and am calling Mack Boring to send someone to the boat on the mooring, I never knew all this was so complicated, C"

10-14-2009, 06:09 PM
"This engine sat a while as the hours are so low. You can either take it out for a good run, and see if it cleans up. Then again Mack Boring are good people and have been at it a long time. Let us know what was done please. Thanks Ron Cairns"