Veg Heat Exchanger

[Jenkosowls]

Running 100% reg with bit of 2 stroke and i intend to run it for as long as possible with the ever rising fuel cost. and since where having a few cold spots and i start work at around 430 in the morn my car runs a tad lumpy as expected till warm. Obviously the way to solve this would be to run a heat exchanger. iv seen one on ebay and it looks pretty well made runs to glowplugs in an aluminium casing and gives a pretty good explanation of it all.

What i want to know is if any ones done anything simular? any home made ideas? iv seen the ones that run along Side with coolant pipes but that wouldnt work right away really due to heat transfer and warm up times for coolant.

Any ideas cheers

[mark_airey]

You already have a heat exchanger under your fuel filter just need to wait for the coolant to heat up a bit before its any use.

Easiest solution is to mix in a small amount of petrol with the veg to thin it down a bit in the colder months and you should be right, also keep an eye on the fuel filter as it will clog pretty fast if its the first time you have run veg.

[n0v0s]

I've purchased a flat plate heat exchanger (fphe) normally used for central heating. They are a very efficient way of transfering heat due to the counter current flow system that is employed. Will probably impose quite a restriction but a few other little tweaks should help.

[ginge191]

insulate the fuel filter housing??

as hairy said, you already have a heat exchanger under the filter, looks like a maze but runs the warm water and exchanges heat through there...

[Megamonkey]

Theres the penny modification to the filter housing you can do, basically just diverts all the fuel through the heat exchanger in the fuel filter housing!


http://www.vegetableoildiesel.co.uk/for ... 455&page=1

[cully]

dont forget if your heating your veg you might want to consider close looping the fuel return to stop the heat being lost back to the tank

[THE_Liam]

This is an idea I've been toying with. When I used to do aircon recharging, I had this electric heating jacket that I used to wrap around the refridgerant bottle when it was getting low on pressure, and this would make the refridgerant flow faster. It used to heat up within a minute, and was almost too hot to touch once hot. I had an idea of getting some ally pipe, doubling it back on itself a few times, and then wrapping it in the heating jacket which would be wired into the glow plug circuit, then connecting this rig directly to the pump, possibly mounted on the inner wing. That way, when the glow plug circuit was activated by the ignition, it would instantly heat up the veg oil in the pipes and within a few cranks the heated oil would be in the cylinders...

It's a crude idea, does anyone think a more sophisticated version of this would work? This is pretty much what I used - http://www.carairconditioningsupplies.c ... oductid=52

[cully]

let me find what i built when i was running 100% veg on a 1.5 corsa

engine bay!



moded cav fuel filter heater has the low temp thermostat drilled out so coolant passes all the time



electric fuel filter heaters built into a chamber



control box controlling the electric heating

[n0v0s]

Closed loop with the original shitty filter housing is probably not a great idea. If air gets in the system then you'll be sure to have some fun..

[Ruan]

No need to close loop, there's a big pot of Diesel in the tank it returns to, and only fills when it gets low

[cully]

you mis the point off close looping the return

the return fuel is hot as you have just heated it! you want to keep the veg hot to get a better burn with less varnish!

[Ruan]

Yeah, but that's no problem, because it sucks from the pot in the tank, which is already heated, so you don't lose the heat into the big lake of veg in the tank, just out the pot?

[cully]

you loose a lot of temp from the fuel in the fuel lines as they are in free air under the car

[Dum-Dum]

HDis have a glow plug coolant heater that you could use as i reckon youd get one off someone breaking for a couple of quid.

[Dave]

I have one of these, has 4x glow plus in I think.

[silverzx]

Which of these options is the easiest?

[mark_airey]

Which of these options is the easiest?

Clearly mine of adding a little bit of petrol to the veg at cold times of the year

I need to reply to your PM too! :o

[Jenkosowls]

i was thinking of getting the coolant heater off a HDi to warm the heater matric area up to have quick heating. i suppose could do this to with a sort of inline heater for the fuel. but how would i go about wiring this up so its not constantly on?

As for ruan i can see what you mean regards the pot in the fuel tank as i opened it up to check the pick up filter and pored my veg straight into it the pot remained a higher level than the rest of the tank. i assume this is there so that when you go round a corner you dont end up sucking up nothing

[Dave]

I do what mark does, and just add about 5% petrol to my veg, it thins it out, helps lower the flash point, so gives it abit more power mid range, and alot more power high up because of the thinning, also helps cold starting alot!

[silverzx]

Is it a lot safer to pre-mix the veg/petrol or is it fine to just "chuck it in"?

[Dave]

chuck it in, seriously as long as it only like 5 or 6 or so litres a tank. If you've got quarter of a tank just stick 2 litres in or something. If I had to mix it before I put it in everytime I just wouldnt be arsed.

[mark_airey]

I use the same "meh........that'll do" technique described above by Dave

[silverzx]

Nice on lads. Will brim her up with veg and pop a £5'er in at the petrol pump. Uh-oh!

Edit: Oh wait, a £5'er from the pump is only like 3L.

[mark_airey]

anything between 5 & 10% should be fine mate, shouldn't matter too much now as its a bit warmer anyway, if you have just started with veg I would stock up on fuel filters and carry one round in the car + an appropriate allen key as you will be changing it a few times over the next few 1000 miles until you get the years of crap out of the system

[Dave]

I use the same "meh........that'll do" technique described above by Dave

Cant waste time worrying about stuff that dosent matter

[silverzx]

anything between 5 & 10% should be fine mate, shouldn't matter too much now as its a bit warmer anyway, if you have just started with veg I would stock up on fuel filters and carry one round in the car + an appropriate allen key as you will be changing it a few times over the next few 1000 miles until you get the years of crap out of the system

Been running on it a while now, done about 4000 miles on mixtures already.

Only in the last month have I started running pure.

Only changed the fuel filter twice so far as well, once after first 200 miles of mix and once not all that long ago.

[mark_airey]

Cant waste time worrying about stuff that dosent matter

you mean there are more important things keeping engine internals internal

[Ben]

Surely there is enough fuel in the pump and the line feeding the pump for the first mile or so, by which time the fuel filter housing is heated? So would heating the fuel before pump achieve anything?

[cully]

put some veg oil in the fridge ben it will turn to a solid or to a thick treakle and the pump can't suck this from the tank

[Poodle]

Regarding the "penny" mod, how the hell do you persuade the stat to let go of the housing?