Breather hose on 2qm20

[Mattyb]

Hi guys

I am currently motoring along sitting on 2000 Ron and there is quite a lot of smoke coming from the breather hose on the engine. Actually smoke is probably the wrong word for it. Is this normal ? I have the engine bay open and can see the residue coming up through the cockpit doors. My oil level was fine and everything seems to be normal??? Should I be worried?

[Mattyb]

Oh and it's the breather hose that comes off the side plate by the govenor. Seems to be white but doesn't smell like oil or diesel or steam. Just smells smokey if that makes sense. The water pump">raw water pump isn't leaking so I don't think it's coming in through there. Hmmmm

[cal40john]

Look to see if open end of the hose fell off of a fitting on the intake somewhere. The diesels I've seen return the crankcase bypass to the intake on the engine.

Even the old Atomic 4 had you place the end of the breather tube in front of the spark arrestor in front of the carb.

John

[Mattyb]

I had a look but can't see anything. Changed the oil and filter, maybe that will do the trick. Judging by the amount of grit and dirt in the fuel in the water separator filter the oil probably hasn't been done in ages. I bought the boat just a few weeks ago

[Mattyb]

The manual states that the breather hose goes back into the air intake but I can't find any connection there. I can rig something up though. However is there usually meant to be quite a lot of smoke coming out of the breathers??

[DeepFrz]

The breather tube usually comes off the top of the valve cover.

[Sailmonkey]

This is relatively normal for an older engine. Many engine also do not return the crankcase breather to the intake, usually an example of a poor or less sophisticated marinization. Our Kubota based phasor does not return to the intake either, but is on the to do list to keep engine bay odors to a minimum.

Crankcase vents can come from the valve cover, or the side of the block, just somewhere to relieve pressure from the crankcase is all that is needed.

[DeepFrz]

Interesting. The only ones I have seen with a vent on the side just went down the side of the engine and dripped. I guess this is an improvement over that setup anyway.

[wanderer1]

Your breather hose should be hooked up to a small fitting under your air intake.If this isn`t hooked up,your crankcase ventilation will eventually plug up and the engine oil will start blowing out your dipstick.

[Mark Zarley]

remove the cap where you add oil, then place cap back over hole with out turning or tightening. Start eng, and run up to speed. If the cap dances around due to excess crankcase pressure, new piston rings may be in your immediate future.

[Mattyb]

Thanks wanderer. I saw that in the manual after posting this but there is no fitting on the intake. I have since changed the oil and filter and routed the Jose so it points at the air intake and problem solved !!!! Still a tiny amount of smoke coming out but nothing of concern now.

[Mattyb]

Thanks Mark I will give it a shot today. Am going to put a new engine in after cyclone season passes so hopefully will be ok till then!

[Mattyb]

Mark I did what u said. Could feel tones of air coming out of the cap. Guessing its not good news!!

[charliehows]

my 2 qm20 goes from strength to strength - i've changed the oil probably a couple of times more then necessary but it makes a lot of difference. My breather is just a tube down the side, puffs a bit, never bothered me, but i might run it round to the air intake when i got nothing better to do. My eng was pretty neglected when i got it, over 3 years now ive cleaned it up, fixed all the ancillaries and by running it properly, ie warmups, reasonable periods of running, regular running, running up to full power when its warmed up for short periods, now it idles like an old harley, runs clean and reliable. Dont chuck your engine away without giving it a chance, they can be a pretty good engine if looked after.