Webasto exhaust "heads up"

I've been beavering away learning as many of the systems on my boat as I can but regret to say I haven't paid any attention to the Webasto. I had been warned by the Sure Marine guys about problems with rusting exhausts. So...I discovered "it got me." The exhaust connection to the Webasto has rusted out. Pretty much looking at a new heat exchanger ($1200 US) and possibly a whole new unit. In the meantime, no Webasto heat up north on our cruise. We are in Port McNeil and I'm not dealing with it here.

The schematics from Sure Marine indicate the exhaust should be located a minimum of 36" above the waterline...pretty much impossible on a KK42. My exhaust outlet is no more than 14" above the water. The do have a stainless steel "water box" that will prevent water ingress. I wonder if a "rubber" bung in the exhaust port would be an option while traveling, with a note to remove it at the switch or some other better fail-safe.

I should say the guys at Sure Marine have been very helpful in the past and also the most recent event.


Jim
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Hi Jim,

Not sure if this would help with your Webasto install, but I had to replace and re-route the exhaust for my two Wallas Diesel Furnaces and they require a minimum of a 12" splash riser to prevent the ingress of water.

Details can be found here.

Boydski said:

Hi Jim,

Not sure if this would help with your Webasto install, but I had to replace and re-route the exhaust for my two Wallas Diesel Furnaces and they require a minimum of a 12" splash riser to prevent the ingress of water.

Details can be found here.

Click to expand...

It's not possible for me to have that splash riser on my setup because the exhaust outlet is right near the ceiling of the lazarette.

For the short term, I wonder if some sort of epoxy putty like JBweld or some such product might hold things together for the summer. Not a permanent solution I realize. I'd only do it if it was safe.


Jim
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JB Weld won't work on a car exhaust.

My Wabasto exhaust is 10' long (max) and it's close to 3' above the WL. Can't see if the loop's there but I just found my mirror so will check. I just had my furnace unit rebuilt/cleaned ... whatever they do. They (Sure Marine) said it was very sooted up and recomended I burn kerosene. I'm switching. As far as I know I've not had any rust issues. Very soon I'll be using it so I'll do my best to inspect the exhaust. Thanks.

Jim: A plug will work well just remember to hang a tag on the thermostat or breaker so you don't forget. Sure Marine also sells hard SS exhaust lines.


We had a Webasto 2010 and the same thing happened. We sent the unit to Sure and after about $1,800 we had a completely rebuilt, like new unit. A lot cheaper than replacement. Stay warm. You might have to run the generator for heat now though.

I did the same thing years ago after losing my heat exchanger and evaluated the poss of a change in exhaust. A wise, old boatman recommendtion the expansion plug in the exhaust and that's worked fine for the few dollars cost. As stated, just have to remember to remove it or she won't ignite.

Glen

I bought some "Tech Steel". Rated to 500 F. However, I phoned Sure Marine and the rep said absolutely do not use an epoxy steel product. Exhaust temperatures can exceed 700 F. So, back to using the genny to run the space heater. They have something called a "Water box"
http://www.suremarineservice.com/W002-744.aspx
...but that requires 6" of clearance above the thru hull for the exhaust, so that won't work in my situation as the thru hull is very near the ceiling of the aft lazarette. Here is a heat sheild at the ceiling and the exhaust pipe has an insulated jacket.

In that case, he says yes to the rubber bung or even a tapered wooden plug, so I will tap one of those on for now. The unit is disabled.




Jim
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During my refit we relocated the Webasto from the ER to the Lazarette. In the process ensured we installed a high loop, and the only way to do it was to intrude into the cockpit. You can see it in the photo - it is under the stainless box against the transom. The exhaust is heat wrapped and the enclosing box has ventilation. The box is warm to the touch, or to sit on, when the Webasto is running.

RNL said:

I did the same thing years ago after losing my heat exchanger and evaluated the poss of a change in exhaust. A wise, old boatman recommendtion the expansion plug in the exhaust and that's worked fine for the few dollars cost. As stated, just have to remember to remove it or she won't ignite.

Glen

Click to expand...

Yes. I just got one as well and I've already stuck it in the exhaust. I don't want water flooding into the lazarette when I'm in a following sea. The Webasto is disabled right now. I will have to do a Re&Re this fall. I have engine heat to use when steaming places. The rest of the time I'd either be using it or have it plugged as well. The rising loop is a great idea, but more invasive and costly. I'd rather try the bung for now. I'll repost when I find out how old this unit is.


Jim
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Insequent,
I think you've about optimized a Wabasto installation. Good work.

manyboats said:

Insequent,
I think you've about optimized a Wabasto installation. Good work.

Click to expand...

Yes it's a great approach.


Jim
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