Engine bay condensation - Tube heater on a timer?

Condensation is warm, moist air hitting a cooler surface. So, either keep all the surfaces the same temperature (which is almost impossible), ventilate the moist air away or dehumidify.
The cheapest is obviously ventilate. Remove the blanket from the engine and that issue will be solved. You only need a tube heater there if it's going to be well below freezing. Dehumidifier in the engine bay will only work if you seal up every air gap and simple ventilation has to be the better answer.
Your garage tools will fair better if you can insulate the garage a bit better (to reduce the temperature difference) and increase the ventilation.
 
I don't do it myself but know quite a few who do. I imagine it's done on the same principle why some similarly cover car windscreen in winter. They still get wet but somehow do seem to prevent frosting up. I can't quite get my head around how? either.

I think the idea with the windscreen cover is to stop moisture/frost settling on it, I don't think it's to do with actual temperature per se.
 
Hi all,

Apologies for what's probably another dumb question, this is our first winter with a boat (6.5m Sealine).

We were told that basically, if the temperature stays above -5C, then a duvet over the engine is fine. Lower, and i need to winterise the engine, which I now know how to (but haven't because the weather hasn't prompted me to yet).

However, on Thursday I went down to do my 2-week start-her-up-for-15-minutes... and on removing the duvet, the whole engine was covered in moisture.

This can't be good right?

So what I'm thinking is one of these 40W tube heaters, duck-taped (to its bracket) into the engine bay, probably on top of the battery covers to give it some height in case of flooding. Then to slap it on a timer, to come on at the warmest part of the day ~1400h for an hour, just to push out any built up moisture.

Also thinking to do the same in the cuddy, as the fabric feels a bit damp.

Is this a kinda normal plan and the right thing to do? Or mostly pointless?

I have had boats with inboard diesels here on the east coast for 35 years. The oldest is 25 years old and been in my posession for 17 years. I have never heated a boat when not on board, always maintained ventilation, have never put a blanket/quilt over the engine, always kept the bilges as dry as possible, always run the engine under load to full temp at least once per month if in the water (if can't be run under load then don't run it) and always frequently sprayed all over with wd40 (there are other types that may be better) and have never had a corrosion problem.

Www.solocoastalsailing.co.uk
 
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I have made two sausage shaped bungs, per side, using tubular plastic roll and immersion heater insulating material and wedged it into the engine intakes. I also have two 35w tube heaters, one under each engine and left on 24hrs. This is the first year I have done this and what a difference. Engines start easier and whole boat interior is bone dry. I also have a dehumidifier running in the main cabin. I used to have that damp feeling when entering the cabin constantly throughout the winter months. I live quite close to where my boat is moored so I am down the boat fairly regularly to keep an eye on things.
 
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Hi all,

Apologies for what's probably another dumb question, this is our first winter with a boat (6.5m Sealine).

We were told that basically, if the temperature stays above -5C, then a duvet over the engine is fine. Lower, and i need to winterise the engine, which I now know how to (but haven't because the weather hasn't prompted me to yet).

However, on Thursday I went down to do my 2-week start-her-up-for-15-minutes... and on removing the duvet, the whole engine was covered in moisture.

This can't be good right?

So what I'm thinking is one of these 40W tube heaters, duck-taped (to its bracket) into the engine bay, probably on top of the battery covers to give it some height in case of flooding. Then to slap it on a timer, to come on at the warmest part of the day ~1400h for an hour, just to push out any built up moisture.

Also thinking to do the same in the cuddy, as the fabric feels a bit damp.

Is this a kinda normal plan and the right thing to do? Or mostly pointless?

I think..
Your new heaters will eliminate most of the problem if you place one under the engine. I use a 40watt bulb in an inspection lamp (cos it is there) on a timer to come on overnight. It just keeps the block warm enough on all but the coldest of UK snaps. You should also increase ventilation to the max. And use the moisture traps suggested, in any unventilated spaces.

As the others have said, you could use a dehumidifier but that has it's own downsides.
 
Cheers all, gonna give it a go this weekend (shoulda been last weekend but ScrewFix's "next day delivery" didn't happen).

So I've now got 2x 40W tube heaters ready to chuck onboard. One for engine bay, other for cabin.
 
Might be worth getting a cheap Argos oils filled radiator with a built in thermostat, it will keep the chill off
As others have said, do let some air circulate and open all the internal doors when you aren't there to allow the air to circulate
The price of a pint. Week on leccy is a small price to pay, plus when you go to the boat it ain't freezing!
 
And for completeness... here's a picture of the BEAUTIFULLY INSTALLED tube heater.

Installed by the fine art of Duck Tape, to the top of my battery covers.

I might upgrade to cable-ties once I re-strap the covers back down to make it more long-term.

:).

heater.jpg
 
Vodzurk,

Have you considered the potential hazards of an ignition (thermostat arcing) source near a charging battery (Hydrogen gas) when ventilation may be at a minimum?
 
Vodzurk,

Have you considered the potential hazards of an ignition (thermostat arcing) source near a charging battery (Hydrogen gas) when ventilation may be at a minimum?

Thanks for the feedback!

The heater is up full, always on. I don't believe the thermostat ever triggers the circuits relay off. I could be wrong, but believe the circuit stays open, and it doesn't give any telltale hum of arcing.

Also, the wire is fed into the bay from above, leaving a 1cm lip of the wooden hatch open above the battery, so any hydrogen should hit the wood and roll out on the incline. Probably all the bloody heat too... mmm.

The batteries are also sealed types, and I believe gel... Though I don't know if that keeps any hydrogen contained (I imagine not, else boom).

Meh, will see about just chucking it on top of the engine at the weekend.
 
Might be worth getting a cheap Argos oils filled radiator with a built in thermostat, it will keep the chill off
As others have said, do let some air circulate and open all the internal doors when you aren't there to allow the air to circulate
The price of a pint. Week on leccy is a small price to pay, plus when you go to the boat it ain't freezing!

Yep, £2.50 per week for 80W of heaters + battery trickle charging. :).
 
I haven’t read all this thread, but I use those cheap plastic dehumidifiers that have a giant tablet inside. They are cheap, requires no electricity, all they need is replacing the tablets and draining the water every so often
 
The heater is up full, always on. I don't believe the thermostat ever triggers the circuits relay off. I could be wrong, but believe the circuit stays open, and it doesn't give any telltale hum of arcing.

Sorry I'm struggling with your reasoning; can you be 100% certain that at maximum temperature setting the thermostat will not operate when the temperature is exceeded. If not it sounds more like an on off switch.
My experience of mechanical contacts when operating, they simply click as they draw an arc and not hum.
Be aware do so called sealed gel batteries also emit gas! However, whichever way you look at it, contacts in an explosive atmosphere have dangerous consequences, not least life and neighbouring property. Please see boat safe scheme regulations, regarding venting of batteries.
Not my intention to offend but I think your surveyors advise would also help to cover you and all events.
 
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I always winterize the engines .. just to be safe. You never know if you will get a real cold winter. Hereafter I put 3 x moisture traps (each 6 Euros) in the cabin (I have a 37' boat) and make sure that doors and windows are completely closed/ sealed so the traps will not just pull moisture in from outside. It works perfect. The interior stays dry and I have no mold building up. No smell at all when reopened in the spring. The engine I wash down and spray with a good moisture protection oil (Duck oil) and then I leave 2 x moisture traps in the engine bay and make sure the bay is well closed/ sealed. Also here once opened everything is dry.

It is a very cheap way to protect your boat for the winter season.
 
At this stage I feel like putting a torch to the whole bloody boat.

Well, that would certainly keep any freezing at bay.! Don't know if you are serious, but if you are feeling so bad about a minor item such as this, then brace yourself should anything really bad go wrong. Boats tend to be a constant stream of problems to solve/fix, especially if they are somewhat older, so chin up.
 
Meh, will see about just chucking it on top of the engine at the weekend.

Can you slide it below the engine at all? On my Sealine S24 I have a small (possibly 45cm) tube I've attached to a piece of MDF that I slide under the engine; I figured the rising hot air should do some good. The base keeps it above any muck (there's a small drip from rainwater somewhere I can't find).

Have enjoyed your videos; look forward to more
 
Well, that would certainly keep any freezing at bay.! Don't know if you are serious, but if you are feeling so bad about a minor item such as this, then brace yourself should anything really bad go wrong. Boats tend to be a constant stream of problems to solve/fix, especially if they are somewhat older, so chin up.

Not serious, just frustrating sometimes with relation to advice. I've already thrown over £2000 at it over the first year following "safety advice" on here. Might as well attempt to paint the Forth Bridge on my own.
Boat only cost £6000, and even a year later I still believe it was in excellent shape on purchase. I still believe 90% of the advice was unnecessary. Had a bad day at work, so wasn't on my best yesterday, now back on track :).

Can you slide it below the engine at all? On my Sealine S24 I have a small (possibly 45cm) tube I've attached to a piece of MDF that I slide under the engine; I figured the rising hot air should do some good. The base keeps it above any muck (there's a small drip from rainwater somewhere I can't find).

Have enjoyed your videos; look forward to more

It is tempting to chuck it under the engine... but the V of the hull has that as the lowest spot... and in monsoon conditions, if the canopy gets battered, it sometimes does let upto an inch of water in there. Sounds similar to what you might be having... impossible to keep it 100% dry, especially during storms. I'll have a think about it, because you're probably right in that being the best place for it. It's just a bit difficult to get to the spot, and not sure I could temporarily secure something there.

It's bone-dry presently as I'm trying to do everything I possibly can on my own... but that seems to be limited to cleaning it. So clean it I shall. You could eat your lunch off the other side of the engine bay. I think at this rate I could enter myself into the Olympics Contortionists team... if one existed.

Thanks for the kind words re our videos :). Hopefully we'll have some more at the end of March. We had intended to keep getting out through winter, but the missus now realises how cold it gets and has changed her mind. Plus there's some bits n bobs that I want doing before I feel confident in the engine (new sparks, servicing, alternator, pump, gps wiring... -insert endless other things here-)... but should be ready to roll by end of March :). Gonna be damn near pristine by then!

Quite like the look of the S24's. Always on the lookout for options on what the next boat should be (though not for 2 more years... learning on a "cheap" boat first [ha, cheap]). That said, I think we'd probably lean towards S28 or 305/310 with twin engines... my big milestone in 3 years is to aim to get to France! Laughable to some who do it frequently, but hey, we gotta start somewhere!
 
Not serious, just frustrating sometimes with relation to advice. I've already thrown over £2000 at it over the first year following "safety advice" on here. Might as well attempt to paint the Forth Bridge on my own.
Boat only cost £6000, and even a year later I still believe it was in excellent shape on purchase. I still believe 90% of the advice was unnecessary. Had a bad day at work, so wasn't on my best yesterday, now back on track :).

Ahh. The thing with advice is to weigh it all up then sit on it while you mull it all over. :D Giving advice is cheap, acting on advice is nearly always costly.
 
It is tempting to chuck it under the engine... but the V of the hull has that as the lowest spot... and in monsoon conditions, if the canopy gets battered, it sometimes does let upto an inch of water in there. Sounds similar to what you might be having... impossible to keep it 100% dry, especially during storms. I'll have a think about it, because you're probably right in that being the best place for it. It's just a bit difficult to get to the spot, and not sure I could temporarily secure something there.

Here's a cheap solution for you - get a pack of Tesco Value nappies (I think it's less than £2 for 20) and keep one in the bilge when you're not on the boat. Since doing that mine has been bone-dry, with an occasional soggy nappy to deal with. It's one of my favourite effective/cheap tricks (especially as a mate bought the nappies when he was on a beer & wine run for me!).

Not sure on your layout, but I drop my heater (on its little base) in front of the engine and then knock it back under using a broom or similar; room's tight for me too). You could possibly position the nappy in a similar way.

I like the S28 too - the extra beam would be nice. Really good to have goals; we're based on the upper Thames but went out the estuary to Southend last year. My Grandad used to go over to France on his boats, so that's on the cards for me too!
 
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