Home made Engine Pre-heaters?

[Mitsuru]

I've got the engine out at the moment.

http://www.practicallyclassics.co.uk/vi ... f=12&t=138

And I have beentold most of the v5 engines use the same size battery as the Chrysler Neon.
The Neon used a 86amp alternator, the v6 has a 160amp alternator, and I can get a bigger battery.
The engine and alyernator used to power a Chrysler Grand Voyager and all it's electricery.

[TerryG]

Multi-point LPG systems don't have the iceing problem, it's the older single point vapouriser type that can suffer but if you have a big enough vapouriser so it isn't over working and it is mounted correctly you should be able to switch straight over at more or less any temperature that we have in the UK. I was running my single point system switching straight to gas when the temp thing in the car was reading -20 after sitting overnight.
I did think about fitting one of these http://www.rimmerbros.co.uk/Item--i-RX1361 but decided it was too expensive and i would rather spend the money on fuel to let the car idle for 5 minutes and warm itself up.

[Mike Whiskey]

Not sure about your figures for power 60kW or 90 PS (german for horsepower) is an engine power figure.

The Kenlowe mains powered hotstart is about 2700 to 3000 watts http://www.kenlowe.com/pre-heaters/cars/spec.html

Thats still going to draw something like 12 amps from your 240v supply.

How are these things used in the initial application? I can only assume they are intended to work only when the engine is running, to speed up warming rather than as a pre heater because the current draw will be very high.

If there were say only 100W each, (and I have no idea what the draw would be) that is still 200W which will pull over 16amps from your battery. A fairly typical battery with 44AmpHour rating would last less than 3 hours, and be pretty unlikely to turn your car over after even an hour...

How much heat that sort of power will actually put into your coolant is open to all sorts of variables, but i bet it is not much.

Incidentally, my schoolboy physics estimates athat a 60kW, 12 volt heater will draw 5000 amps, flattening your battery in about 30 seconds!

I'm happy to be proved wrong, as this is schoolboy stuff, and that was a long time ago (and I've had a drink!).

MW

[rich.]

trouble with leaving your car ticking over to warm up it will be either nicked or get a ticket. ford galaxy/ vw sharons, renault espace have an extra heater would that be any use?

[mach1rob]

is that the ones from hgvs? a mate fitted one to his camper conversion it was fantastic.. i used to "work" as his service crew & in the winters & early morning there was a queue for our service barge....quick warm, bacon sarnies & hot coffee.. happy days.

I suppose one would possibly work, but they're generally 24v, that's one used by MG-R/Land Rover, had one fitted to my 75 diesel, as standard would fire up on start up when the ambient temperature was below 5 degrees C and would run until such time the coolant was up to normal temp. You could fit a couple of options, one being a timer that would start the FBH up at a pre set time, so the coolant would be up to temp for when you came out, or get really posh and fit a remote so you could turn it on from the hallway, and with some simple electriketry, even get the blower fan to come on so the car is toasty warm for when you come out, and all without having to start the engine. The good thing about these heaters, running on diesel they don't drain the battery.

TBH, using 2 glow plugs in a tank is going to drain the battery faster than it'll warm the coolant, most of these aids fitted by manufacturers to help aid warm up are only designed to run with the engine running, just think how much ampage is needed by glowplugs on a diesel to start up, having them running for several minutes will just kill your battery before it's raised the coolant a few degrees, and meaning you'll then need a jump start and be no better off.

[SirTainleyBarking]

The other option is to plumb in an Eberspacher type fuel powered heater. They are designed to bump up the coolant temperature very quickly, at the expense of burning extra fuel and killing your fuel consumption for the first couple of miles.
IIRC The latest LR discoveries have something like that fitted as a compromise in really cold climates. Yes its more fuel consumption, but allows the engine to get up to temperature quicker ensuring that the emissions are kept to sensible levels. Kicks in at -10 or -20 from what I've read. Scares the life out of brand new disco drivers who haven't read the manual the first time it happens as it kicks in with a loud "Whoomp"

[SirTainleyBarking]

Incidentally, my schoolboy physics estimates athat a 60kW, 12 volt heater will draw 5000 amps, Setting fire to your battery in about 30 seconds!

I'm happy to be proved wrong, as this is schoolboy stuff, and that was a long time ago (and I've had a drink!).

MW

Fixed it for you

[JPB]

Won't all of that acid that lives in there put the flames out though? Problem solved.

[rich.]

would the gas ignite?, ive seen a couple of batterys explode...

[sierra3dr]

Didn't I suggest a smaller home made kit idea a while back? Oh look here it is!

so you have,a topic I've never seen before