Seawater in my Webasto

Plevier

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I recently serviced my Webasto 3500 (with many thanks to David2452 for advice) and it was working well.

This weekend we did the Royal Escape Race in pretty rough conditions. Tried to fire up the heater in Fecamp to dry us out a bit - failed, with 1 flash from the diagnostics (which means failure to ignite, suggested causes no fuel or failed flame detector). There was no hint of warmth from the vent during the cycle (but plenty of air) so it was completely failing to ignite, unlike the problem before I serviced it which was failure to detect the flame even though you could feel some warmth.

Had a quick look at the heater, found seawater dripping from the condensation vent in the combustion exhaust and all the lagging wet :(

The heater is mounted right up under the deck on the outside maybe a metre ahead of the transom, and the exhaust fitting is at the same position on the transom. There is no spare height for a swan neck in the pipe, in fact it dips and the condensate drain is at the lowest point. At times we had the lee rail well under and clearly the exhaust has got submerged and water back into the heater.

I wondered if this has happened to anyone else and what the likely ill effects are? Having had the heater apart and seen what there is in the combustion side of it, I can't really see why it would worry it. I would have thought it would drain out and be OK.

Before removing and stripping it again, I wondered if taking the pipes off and blowing a hair dryer (or paint stripper gun) through might help?

Also does anyone know of a self-closing exhaust vent, or will I just have to get a rubber bung for it - and remember to remove it?
 
You may have got away with it but therere is a possibility of seawter getting through to the air motor. I have usually been able to get them up and running again with a quick strip and dry out. Sometimes simply disconnecting the exhaust and draining it off will enable a start, try running with the exhaust disconnected as a first step and if you have a vent switch run that on full fan for a while first. Over centre garboard bungs work well and a fail to srart will soon remind you to remove it.
 
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You may have got away with it but therere is a possibility of seawter getting through to the air motor. I have usually been able to get them up and running again with a quick strip and dry out. Sometimes simply disconnecting the exhaust and draining it off will enable a start, try running with the exhaust disconnected as a first step and if you have a vent switch run that on full fan for a while first. Over centre garboard bungs work well and a fail to srart will soon remind you to remove it.

My Webasto runs fine. Had it going for an hour today which is a bit depressing for late May.

I would just like to thank you David for your diligent replies to such problems and building up the knowledge in a public arena of such answers.

Because I know, one day, I will have problems!
 
Yes, what is that? I'm sure I want/need one!!

OOPS...just Googled...................Oh, yes I was right I do want one!

You must have a better google than me. As I expected to see, my google points me to screwed plugs for fitting into the bottom of a boat, to be used as a drain when the boat is out of the water. I'm not sure of the relevance of this for a heater exhaust. However I'm always keen to learn new things, so please, what is an over centre garboard bung?
 
David's reply - helpful again thank you - made me blink too! I have worked out what an over centre etc is - but I can't find where to get one!
 
You must have a better google than me. As I expected to see, my google points me to screwed plugs for fitting into the bottom of a boat, to be used as a drain when the boat is out of the water. I'm not sure of the relevance of this for a heater exhaust. However I'm always keen to learn new things, so please, what is an over centre garboard bung?

It's a brass and rubber device, the rubber bung fits easily in the garboard drain hole (or in this case the 24mm exhaust skin fitting), then an over centre lever compresses it via arod and washer affair which expands the rubber to grip and seal in the hole, but everybody knows that surely.��
 
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