Stanadyne fuel heater

[jaky cakes]

Hi folks,
Just bought a Stanadyne inline fuel heater from ebay to help heat my svo mix until my heat exchanger kits in.
The info and diagrams included aare all very good until it comes to connect the unit to the car.
It works. as you'd expect, via a relay - the switch wire of which connects to D+ whatever that maybe.
D+ is also refered to as a "hot wire" which makes even less sense than D+.

has anybody fitted one of these????
any help greatly appreciated.

[andycook]

has anybody fitted one of these????
any help greatly appreciated.

I got one of these a couple of weeks back - off ebay - same guy probably.

I wired it up as suggested in instructions with +ve relay switch wire to alernator charge indicator wire (i.e. so that heater can only come on when engine running.)

The main FUSED +ve wire goes direct to +ve battery terminal.

But i found that all my warning lights , esp turbo light came on dimmly - more obvious in the dark. That annoyed me!, dont know why it happened, but have been slight current drop with power going in parallel through the relay.

So in end I wired it to one of the front windscreen wiper wires - that got a current when ignition in on position (but engine not necessairly running).

Heater works fine - but bear in mind it has an internal thermostat that only operates when fuel temperature below 10 deg C.

I use it in combination with my heater fuel filter unit, over which i have more control - with a manual switch.

[BUSHWHACKER]

Hi folks,
Just bought a Stanadyne inline fuel heater from ebay to help heat my svo mix until my heat exchanger kits in.
The info and diagrams included aare all very good until it comes to connect the unit to the car.
It works. as you'd expect, via a relay - the switch wire of which connects to D+ whatever that maybe.
D+ is also refered to as a "hot wire" which makes even less sense than D+.

has anybody fitted one of these????
any help greatly appreciated.

The 'hot' wire is normally a permenant live feed.

[jaky cakes]

So in end I wired it to one of the front windscreen wiper wires - that got a current when ignition in on position (but engine not necessairly running).

Heater works fine - but bear in mind it has an internal thermostat that only operates when fuel temperature below 10 deg C.

Great minds think alike!
just finished wiring it up- in the dark. quickly tested operation with ignition on but engine off - seemed to get warm quite quickly - which should do the job until my exchager kicks in.
against the advice of fitting instructions - i fitted unit after filter, just before fuel pump to get warm fuel into pump a bit more quickly. after about 1-2 minutes the engine coolant is warm enough to heat fuel running through the heat exchanger i robbed from a redundant combi boiler (see picture). its a plate type exchanger and very efficient it is to. within a few minutes the fuel line is getting almost too hot to hold (45'c???)
so now running on 75% svo (and it is cold up here at the moment) with no problems and runs sweet as a nut - almost comparable to a petrol engine.
I'm astounded at the transformation in engine noise and smoothness all for the price of a few pints. ---- which gives me a good idea!!!!!

[BUSHWHACKER]

How big is that heat exchanger? and where did you find room to mount it?

[jaky cakes]

How big is that heat exchanger? and where did you find room to mount it?

the exchanger is roughly 8" x 3.5" and has to be mounted near vertical to "submerge" all plates. I found a little space in the back right hand corner of the engine bay just behind the diagnostic terminal and below the wiper motor. when i get chance this weekend - i will take and post some pictures for all to see.
You can get these exchangers on ebay - they're al ways for sale - but some are pricey but i think around £30-£40 should do it. Or if go to your local s,c,r,a,p yard/metal recycling centre or council tip - you may find an old boiler (steady!!) from which you could get an exchanger.

[BUSHWHACKER]

Hmmmmm, I'm gonna be replacing my Potterton combi boiler soon so I'll rip into that then. Should find some usful parts in there then.

[Danno]

Excuse my ignorance, but the purpose of a fuel heater in this case is to reduce the viscosity of veg oil so the pump and injectors operate correctly?

If so then if the heater, irrespective of type, is near or in engine bay, the fuel being pumped will still be viscous until it reaches the heater. Therefore putting a strain on the pump?

Am thinking of doing it myself and wondered if it would make a difference.

[jaky cakes]

Excuse my ignorance, but the purpose of a fuel heater in this case is to reduce the viscosity of veg oil so the pump and injectors operate correctly?

If so then if the heater, irrespective of type, is near or in engine bay, the fuel being pumped will still be viscous until it reaches the heater. Therefore putting a strain on the pump?

Am thinking of doing it myself and wondered if it would make a difference.

I had thought about this myself - but figured straight deisel in sub or near zero temp would be more thickerer than summer ambient temp, and the pump copes. also svo is mixed with a thinning agent.- not much of an argument I know but if you back that argument up with the fact that this heat exchanger really does kick some heat out, and that the unused heated fuel is returning to tank, the whole system (tank/lines/filter) gets quite toastie warm quite quickly.

Another unsubstantiated belief of mine is that as the fuel is heated - it expands thus giving a greater volume of diesel - and as combustion fuel air ratio (stochiometric??) is based on volume, we should see an increase in MPG??? - sounds good anyway - but i'm unsure if this expansion in volume is enough to make a difference? does anybody know how much svo would expand from a 10'c to 50'c temp spread??.

******STOP PRESS******
MACRO'S VEG OIL SPECIAL OFFER - 2X20lt FOR £18
BUY 4 USING THIS MONTHS £5 VOUCHER (£30 min spend)
EQUATES TO 38.75 pence/litre.
SO I BOUGHT TEN WHICH WORKS OUT AT 42.5pence/litre