Didn’t quite understand this - the mill? Is the question if the engine is working within proper operating temp? I’m not sure how to check that, but seems a good thing to confirm.
Yanmar 3GM30F light blue smoke when cruising
- Thread starter skunther
- Start date
I am I believe the 3rd owner of this boat. Who knows how it was broken in. Air filter is new. EGR is currently above my grade, but depending on how the WOT for 10 hours goes, it may not stay that way for long.No obvious errors regardless of where you look. I do the same as you and no smoke from a 2GM20F.
Are you the first owner of the boat. The reason I ask is perhaps a previous owner ran the engine too lightly from start and glazed the cylinder bore. I have seen cases where "supposedly" this was a cause of smoking. That theory and $1.00 will get you a coffee in most restaurants.
For the considerable cost of correcting this problem compared to the inconvenience of the smoke, I'd probably forget it. If you have a dodger with an opening panel in the front, run with this open to eliminate smoke in the cockpit. I often get smoke at the start of my 3600 RPM run every month or so and air out the cockpit by opening the panel.
Has anyone anyone mentioned air filter ? I know, grasping at straws .............. causes black smoke not blue but when you get desperate. Exhaust gas recirculation (EGR) valve and hose clear ? Anything coming from the hose leading to the EGR under heavy load (leaking rings) ?
Sorry but that's all I got
You are confusing two completely different things here.
When the Yanmar manual talks about revving the engine up before shutting it down, they are talking about putting it in neutral, throttling up from idle to max rpm in a short burst,
dropping it back to idle again, and then repeating the process for maybe five times. This is just to blow the carbon out of the cylinders right before you stop the engine.
The other issue is about running the engine in gear at max or close to max rpm occasionally. That is also a good thing to do, but has nothing to do with, the regimen that Yanmar is talking about immediately before shutting the engine down.
Is there any simple way to very the high temp alarm is functional before I go ahead with the 10 hour WOT?
Short the sensor to ground to ensure it does make a sound but that does not prove what temp. it sounds at.
The only acid test is to safely unscrew the sensor and put it in measured hot water to see when it sounds. Messy, sloppy, dirty, blah, but it's the only way to be 100% sure.
The only acid test is to safely unscrew the sensor and put it in measured hot water to see when it sounds. Messy, sloppy, dirty, blah, but it's the only way to be 100% sure.
Is there any simple way to very the high temp alarm is functional before I go ahead with the 10 hour WOT?
Yes there is.
Buy a new sensor and fit it.
You can be pretty sure that it will work.
gary
Yes there is.
Buy a new sensor and fit it.
You can be pretty sure that it will work.
gary
I'm a big fan of Diesel Kleen. I also use Clear Diesel as a stabilizer. I sample about 20 fuel tanks and send the samples to a lab every year. I have about 20 years worth of records. I used to have a few tanks that had issues, mostly low stability, but now they are all good.
The spec for the coolant overheat switch is that it turns on at 217 - 228 F and off at 205 F ("or Higher" ) A good switch would probably not work if immersed in boiling water.. you could use a heat gun or a carefully applied flame.. then check the tip temp with an IR thermometer.
EDIT: previous numbers are from the shop manual, from the parts book the spec is 203 F and 190 F Somewhere around there then... I dunno
EDIT: previous numbers are from the shop manual, from the parts book the spec is 203 F and 190 F Somewhere around there then... I dunno
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Have you checked that the prop does not grass on it. Run the engine in reverse and check if grass blows out the stern.
I do operate in reverse on a regular basis as we dock/anchor/maneuver/etc and I haven't seen eelgrass coming from the prop. Do you mean for me to do something other than this?
Alan, did you run it for 10 hours continuous? Or might just running the heck out of it for an hour or two at a time until ~10 hours cumulative have similar results?
Does anyone know where I should shoot an IR temp gun on the engine to check actual operating temp?
Once the engine is up to temp. you want to shoot the top of the thermostat housing as this is receiving water which has absorbed heat from the block as shown:
This is the hottest cooling water in the system. Look for 160 to 185 deg. F depending on the engine load:
UPDATE:
With intention of doing the 10 hour WOT piston ring “re-set”, I’ve done two sessions of 30 minutes each of 3200 rpm under load, and am now noticing some diesel leaking from the forward starboard engine mount (it seems to be coming from a plate between (but not inline with) the secondary filter and IP (see attached pic).
I’m also now noticing some gear fluid leaking from what seems to be the joint between the transmission and engine block, though I have been unable so far to definitively identify the source.
Any thoughts on this? It’s resulting in a new unburnt diesel smell in the cabin every time we motor, which isn’t great for the wife and kids…
With intention of doing the 10 hour WOT piston ring “re-set”, I’ve done two sessions of 30 minutes each of 3200 rpm under load, and am now noticing some diesel leaking from the forward starboard engine mount (it seems to be coming from a plate between (but not inline with) the secondary filter and IP (see attached pic).
I’m also now noticing some gear fluid leaking from what seems to be the joint between the transmission and engine block, though I have been unable so far to definitively identify the source.
Any thoughts on this? It’s resulting in a new unburnt diesel smell in the cabin every time we motor, which isn’t great for the wife and kids…
Attachments
Well, we know it is NOT leaking FROM the engine mount. But what is leaking is hard to tell from the photo.
You might try putting some bits of toilet paper around the banjo fittings, and any where else you suspect it could be leaking, and see what gets wet. You may have to run the engine to get it to leak.
Greg.
You might try putting some bits of toilet paper around the banjo fittings, and any where else you suspect it could be leaking, and see what gets wet. You may have to run the engine to get it to leak.
Greg.
Any way you can insert an arrow to show where the leak is from ? I can't make anything form the photo and I know you "have to be there" when dealing with fuel leaks as they are near impossible to see.