Heated Fuel Filter unit

[andycook]

Was chuffed to discover tonight that the Fuel filter assembly on my UK 4runner is a heated system. There is a fuel heater relay in engine fuse box, a pair of wires going to water sensor on base of filter.
Also 2 pairs wire on top of filter, 2 go to heater system and 2 go to a vacum switch.

Edited: 6/9/05
Figured out the wiring now - heater relay works, and also fuel filter heater assembly gets hot if I bypass the vacuum switch.

Not sure when and how the vaccum switch comes on ??
anyone any ideas, does it sense thicker fuel i.e. cold diesel?

I might install a bypass switch so that I can bypass the vacuum switch and heat veg oil mixture up

will be usefull as i am running on more vegoil and heater will help make the veg flow better

[andycook]

vacuum switch function

Can anyone hazarda guess on how the vacuum switch on the heater fuel filter on my truck works?

would it be on all the time, when it detects fuel flow?

or would it be more "intelligent" and only activate when the fuel viscosity increases due to cooler fuel temperature?

unsure if it is bust or not.

[andycook]

Fitted a dash-mounted manual bypass switch to overide the vacuum switch,
and a LED on dash to indicate the filter heater is on.

but want to link the bypass switch into a timer - preferably thermostatic.
wonder if the glow heater timer/relay (the longer heating one after intial warmup) would be appropiate.
this will mean it automatically turns off when engine gets to heat,
then my yet to be installed heat exchanger can take over.
otherwise will need to get hold of another thermostatic switch, controlled by coolant temp.

Also got an inline fuel line heater off ebay yesterday. that has inbuilt 10 degC cutoff for heater. Going to fit that for additional fuel line heating. Need to wire a dash-mounted LED indicator light into that too.

Will post pics of the mods when done.

[kitesurf_phil]

Good work Andy. Keep it up. Apparantly the only Surfs that have the relay and heater are ones with the Winter pack (like mine)

[ChasesDragons]

ooooh ohhhh oooooooooh! fuel heaters and vegoil, my fav subject!

Mine: 1996 (Nov), KZN130 KZ 1TE engine.

I have just recovered from my £1200 bill for a screwed pump, courtesy of vegoil (WVO). And wanna try again

What kind of VO are you guys using? - SVO? SVO with dino? WVO (my undoing) or WVO and dino?

Andy - any chance of pics with wires going into the filter etc?

Warmest Regards
Udhi

[andycook]

pics attached

Two Pictures of heated fuel filter - that came with my 4runner (winter pack)
2-wires goto a vacuum switch - I have added over-ride wires to a manual switch (on dash), and also to a relay, that will be linked to a thermostatic switch when i get one.
and the other 2 wires on filter are the heater itself - I have wired in an LED to this (on dash) so i know that the heater is on

Also attached a pic of dash control lights and button.
and a pic of the inline fuel heater.
-unfortunately I cannot get the inline heater and LED to work together. If wire in series - the LED hogs all the power (even though its wired on earth side of heater), and heater doesnt get warm.
and when in parallel the heater takes all power, so LED doesnt come on.
I also tried wiring through a relay, so when power goes through heater, led cicuit activated - didnt work.
the heater has an internal thermostatic switch, goes off at 10degC


Why did the WVO kill your pump?

[NeillOP]

My 4Runner has the same thing, three sets of wires going to the fuel filter. There's nothing in the handbook about it, but I did find this
http://www.showmesome.info/hilux/info/manuals/1KZ-TE/ (go down to fuel temperature sensor circuit)
I know it's for a KZTE and not a KZT, but is this any help?

[ChasesDragons]

Gentlemen, as usual a thorough response - Thnx.

I used this stuff from a Biopower (?) representative in Manchester, essentially filtered WVO which was pretty thick. Apparently needed thinning with White Spirit or 75% diesel (mebbe 50, I forgot). Anyways, I think it needed further thinning, and fats settled out of it during winter, making the engione cut out/starve under load. One day, smoke everywhere, unable to rev more than 2000 rpm and very little load was tolerated.

Took it to a Diesel Specialist who claimed it had to be reconditioned, costing 1200 - I am SURE that I could have bought a new pump for that. But, I think it needed a lot of "diagnostics", tank taking off and clearing, lines clearing etc <yawn>. He did note a hefty amount of "greasy/waxy ****" in the lines/filter. The vehicle is since fitted with an extra clear fuel filter, after the OEM and before the inj Pump to keep tabs on any more of this substance appearing.

Anyway, I now wanna try real Methyl Ester BD or look into using a 50% SVO:50% Dino, if I do not manage this, the £1 a litre lark is gonna kill me.

Any idea where I can get Biodiesel cheaper than Dino? what is the new situation with taxation for SVO?

Hope this is what you wanted to know mate.

Udhi

[Chillitt]

andy, if i post you a soldering iron, will you chop them scotchlocks out of it? hhmmm, heated filter, why havent i got one of them?

[andycook]

i've got a soldering iron somewhere in garage - but thought the locks look neater, than lots of tape wrapped around the solder joins.

[Chillitt]

sorry mate its just cos i'm jealous of the heater! im sure lots of people will leap to thier defence, but i reckon they were designed to hold water next to the wire.. solder and heat shrink for me every time

[Philip]

Thinning Veg oil

Was at Bealieu autojumble over weekend, where i spoke to quite a few Germans re the Fuel Cat unit i have on my car. 2 or 3 of them told me they mix veg oil with between 5-10% unleaded, with no ill effect. He said that once its mixed in tank doesn't seperate and after 3 years no ill effects. Think i'll give it a go, maybe 5% to start. Sounds the way to go if it works.
Philip

[andycook]

Noticed that since I put in relay and wiring for a inline fuel heater i have, that the turbo warning light and others on dash are glowing dimly when engine running.
Currently the relay is wired to +ve battery, earth, and charge circuit wire on alternator. the 4th wire on relay to goto positive on heater is unplugged and blocked off so not shorting.
when i unplug relay the lamps go off.

suspect its to do with the alternator wire. Reason its wired there, is so that relay only switches on when engine running and battery charging.

but its annoying having warning lights on dimly and may hide problems, so will have to re-think the wiring

[AndyLala]

Take your ignition switch signal from the windscreen wipers, the power is on as soon as the ignition is on, and switches off about 2 minutes after the ignition is powered off. passenger side of the engine bay...

[andycook]

Thanks Andy

ive seen windscreen wiper motor, will try that out.


Found a source of thermal switches to control the electric heater:

RS Electrics - they have loads different types of N/C (normally closed) bi-metal switches. Gone for a 40degC one, basically circuit will be broken when its activated at 40 degC
they are a couple quid each.

Does anyone know what the ID (internal diameter) of the coolant hoses that feed cab heater are?

Take your ignition switch signal from the windscreen wipers, the power is on as soon as the ignition is on, and switches off about 2 minutes after the ignition is powered off. passenger side of the engine bay...