Hey all, Ive got a Yanmar 4JH2E with unknown hours (but assume pretty high). I'm concerned about it smoking. Blue smoke, especially on start up but even when warm there's a noticeable amount. Now I've seen some boat diesels that have enormous plumes when starting and running and this is nowhere near that. I never have to add oil between changes. Usually blue smoke means worn cylinder walls and piston rings - time for a rebuild. But this engine starts instantly - I mean instantly, even in... Read more ..read more

I have a new Yanmar inboard diesel on a big wooden sailing boat. I have just fitted this new engine. The Yanmar comes with engine mounting feet that have twin holes. (see attached Photo) I guess these mountings are intended to be mounted by bolting the feet directly to the engine carrier. I would rather mount the engine to rubber engine mountings. (As I have in the photo) can anybody help advise me on their thoughts on a) should I fabricate a new mounting foot to have one hole in the middle... Read more ..read more

I have yanmar and lub oil preasure is 25 psi at idle and when engine runing long time preasure go down until 20 psi that is normal ..read more

Hi there, I have a well maintained 2000 hr old motor in my boat that runs like a dream. I noticed yesterday that there was oil in the coolant and I'm hoping for some advice. The motor has a sea water cooled engine oil cooler so no chance of oil in coolant from that source. I'm guessing this leaves the possibility of a head gasket or crack some place? The thing that makes me wonder tho is that the engine oil is ready for a change now that it's 100 hours since my last service and is black... Read more ..read more

"I purchased this boat, a 1981 "I purchased this boat, a 1981 Stevens 47, in March of 2008. It has a Yanmar 4JH2-HTE 75hp turbo/intercooled diesel engine that was installed in 1992. At the time of my purchase the engine had approximately 3500 hours. It now has about 4000 hours. It has always run great for me. It has always put out a small amount of light grey smoke at idle and under load but not anything excessive, barely noticable really. It also would put out some black smoke... Read more ..read more

"Hi Guys, I have an old YSE "Hi Guys, I have an old YSE 12 and the fuel pump doesnt seem to be working, it does not have the preassure to supply the fuel through the high preasure fuel line to the injector. it is an old pump, very simple construction with a piston like ram on a spring in the rear that gets pumped to supply the preasure to force fuel through a ball bearing and spring set up on the outlet side. when I take the high preasure hose off the outlet and crank the... Read more ..read more

2018 4jh80 wont start. We have ultraflex throttle controls at the helm which show no errors. Powers up but when the start button is pressed, all I get is the tiniest of clicks coming from somewhere in the motor (probably some kind of solenoid). I checked the lead that goes to the start solenoid -see attached pic- and with the engine powered on, it shows battery voltage; then it drops in voltage when the start button is pressed... that seems wrong to me? Anyone have any ideas... Read more ..read more

I am currently experiencing an error "rudder cylinder control pre-failure SPN: 522016 FMI: 7 DTC: P1825" on the stbd side of my JC10 unit. The manual doesn't have much information regarding all the possible causes of the error. Anybody know a more detailed description of the possible causes so I have a better idea of inspections to make. I have tried replacing the EDV Harness, Solenoids, Steering Oil and Rudder Angle Sensor. Any help and information would be greatly appreciated. It is the... Read more ..read more

My Yanmar 3gm30f ran fine but smoked white upon starting. I had the injectors serviced and replaced all the parts under the injectors. Now I don’t have any compression ..read more

Hi there I have a yanmar 3gm with a kbw gearbox does anybody know if a kmp2 gearbox will fit on that engine. Thanks all ..read more