Some encouraging maintenance

[Browntrout]

I have now had our BP Ilsander 28 hauled out for a bottom job that included new gland stuffing and a new prop with zincs. When we bought the boat it had right at 800 hours on the engine, and now we are at about 875. We have used the engine more than we normally would because we have been taking the boat upriver (Delta SF) to a marina we like, and the way back down is straight on the nose with a vicious "chop" (it should be named something much uglier than that). So these trips take some motoring coming in I have two questions. Our motor appears to be the late model 5101. First, we are getting some gasoline odor in the cabin, stronger in the engine coffin, I mean compartment, but not what I would call raw gasoline. We do not see any seepage or leaks on the gas line petcocks or lines themselves. We do see some varnishing outside of the boat where we had several days of very hot, 103ish weather--that led to some bleed off from a full tank. Inside the boat we have a ragged rubber (I speculate) vent hose that terminates above the carburator spark arrester, I THINK. Should this hose be attached to something? It isn't. It is just hanging there. Would this be a source of fumes? PLEASE NOTE the below photo shows the rubber hose exiting back towards the transmission--the hose with the two screw clamps. This photo is a screen shot from a maintenance video. It is not mine. On my boat, the rubber hose simply points down with a ragged edge to the top of the spark arrestor box.

[Browntrout]

Second Question

Regarding my exhaust, what maintenance should I watch for on this set up? I note there is a drain plug on the bottom of the canister. Should this be drained periodically, or every trip, or...? Sorry for the newbie questions. This is my first inboard engine, and it is a very good running machine. I want to keep it that way. I believe I recall this is a water lift system. BTW< I also note that I inadvertently captured one of the mystery hoses in the water lift photo. The tube in front of the fire extinguisher disappears into the interior of the hull--and I can't trace it. Note that it is copper colored. That feels and smells like old gas that has varnished. Is that possibly a fuel tank vent hose that should be connected somewhere else?

[zellerj]

Gasoline smell - also check out your gas tank. My 1982 Catalina 30 had a slight gas smell, and I tracked it down to corrosion of the aluminum gas tank. I took the tank out and had a new bottom welded on for the repair.

Exhaust muffler - you do not have to drain this until the winter lay-up if it has a chance of freezing.

[Dave Neptune]

#1: The picture is of a PCV valve (Positive Crankcase Ventilation) supplied by Indigo. It is a vast improvement and a good upgrade to the A-4 or any old engine without one. It controls the gasses from the crankcase and directs them directly into the intake manifold to be burned and passed out the exhaust. It is the first thing I personally would add to any A-4!!!

What you have is called the slash tube which hooks to the same vent as above but has no real control of the gasses. It merely directs the vent to the intake of the carb to direct the gasses to the cylinders. However this method lets all of those nasty gasses to gum up the inside of the carb as they pass through. It does work but not as well or as "clean". Some of these gasses will leak out into the atmosphere as they are not controlled and this may be what you smell.

#2: Yes it is a drain for maintenance and winterizing in some climates in fresh water. No need to drain on the Delta.

Dave Neptune

[roadnsky]

Here's a shot of the "slash tube" setup that Dave describes.
Very likely what you have.
IF your "tube" isn't in good condition or making good connection with the flame arrestor, then you'll for sure be getting some crankcase smell.
That screen on the flame arrestor needs to be cleaned as well.

[Browntrout]

Thanks for info

I will contemplate the above. We have some additional clues on the gas smell which i would like to add tomorrow when I have time. Thanks in advance.