Mystery Antifreeze - Ideas welcome!

[KWKloeber]

Dave

It's a wet trap on the discharge from my waste tank. That way the honey sucker fully empties the tank instead of it sucking air as soon as the level drops below the top of the outlet fitting.

The engine compartment arrangement on the C-30 let me run the pvc down to a point (next to the engine stringer) that's several inches below the tank outlet (tank is high, under the port settee.)

The tee forms the actual trap — I wouldn't need a tee there, just 2 elbows, but I have a plug on the run side of the tee (just in case). I probably could have used a 1-1/2" pvc trap w/drain but the tee fit well in the tight spot.

Ken

[Dave Spencer]

Great idea Ken,
(or at least a Good Idea  )  I don't think I have room to install a trap but I have placed a 1 1/2" PVC pipe in my pumpout suction line right at the suction fitting on the tank so that the waste is sitting in a relatively impermeable and inexpensive PVC pipe instead of in a permeable and quite expensive 1 1/2" marine sanitation hose.  I've reinforced the pipe to prevent undue stress in the unlikely event of fore and aft movement since I took this picture.

With my question to Ken and his answer, I fear I am straying off the topic of this thread.  If anyone wants to continue the discussion on this, I can repost in a new thread.

[KWKloeber]

Dave,

I'm not familiar with the tank location/layout.  But, appears that if you turn your exit ell 180,  run the "down" as far as you can, turn back up with two short ells (or a pvc U,) that you could sneak the "up" next to the "down"?

Alternately, run the "back up" above (lying on top of) the "down"?   Using short ells is far from ideal, but maybe all that you can do in the circumstance?  Is there enough vertical drop available to form a wet trap?

k

[sailaway]

I have the same problem all summer I don't loose any antifreeze. Ever winter I loose it all. Mine comes from a bolt on the antifreeze circulation pump. just fill up ever summer every things good.  Charlie

[rmbrown]

Well, as is typical with boat projects, I started with a little mystery anti-freeze and ended up replacing all hoses and mounting the heat exchanger, I hope properly, behind the engine.  For anyone interested, the bolt size was 5/16.  3/4 length worked.

While I had the heat exchanger off, I got to thinking about how poorly the rest of the job was done by the pro I paid so I popped the end caps off.  I could only see through maybe 1/2 of the tubes. I ran a coat hanger through each tube and pushed out lots of crap.  The rubber gaskets on each end were not replaced during the "rebuild".  I doubt the radiator shop where the boat yard took it ever opened it up at all.

Anyway, now when I run the engine, it stays at 165 until I absolutely max it out and spits out water like a firehose.  I'm happy with the results and got yet another lesson into not trusting anyone else to do something where I care about the results.

One question for the group... the brackets I bought from catalina direct (), have rubber pads that fit the brackets and, if the heat exchanger doesn't touch the engine anywhere else, would electrically isolate the thing from the engine.  Problem was, when I installed the pads that way, the heat exchanger was, I believe, actually touching the engine, so I moved the pads to between the engine and the HX.  Is electrical isolation critical here with all the dissimilar metals?  Or is that just for vibration and heat?

[rmbrown]

I jumped the gun and pressed send too soon.  Here's my bracket... https://www.catalinadirect.com/index.cfm/product/4212/bracket-set-for-3-heat-exchanger.cfm

[KWKloeber]

Mike

You correctly ID'd that the Hx can be insulated with the pads.  The pads are meant to go between the Hx and the brackets, and of course, the brackets bolted to the vertical face of the bell housing.  There are differing opinions as to the need to bond the Hx.

Naturally, if the  Hx is bonded to everything else (and everything else is protected with an anode,) then the Hx is protected. If there is isolation between the engine and the anode (say, on the shaft and/or strut) then the protection is not complete. Theoretically, if the Hx is not bonded, them its anode protects the Hx (locally.)  Here is seakamp's position on this:

Hi Ken we have been asked this many times .  is always best to be in contact with the engine when possible   On generators we have a ground stud on our heat exchangers and does seem to extend life  I have came to a point to let the customer do what they see best.  Seems no one has ever pinned down the electrolysis [NOTE: "galvanic corrosion", not electrolysis - kk] issues . there are all kinds of publications on it and they all have their own opinion.

[KWKloeber]

Mike - I also "sent" too soon...

I recommend to customers that the Hx be isolated from the brackets (avoid vibration wear) and that a #14 green bond wire be run from the end cap bolt to a bonded location.  But if your other anodes are not correctly bonded to the engine then your Hx anode becomes a primary one and it's SMALL in comparison to what you think you have for protection (shaft etc).

I haven't, but suggest you try a search on this and there may be more info on the 'net.  Let us know if you find anything different or contradictory?

-ken