yourekiddingright

I posted up this quection on an autoelectricians website and got some really good help but i'm now trying to work out how to actually bring her schematic to life!

Ta very much... well here goes.... I'm working on a veg oil conversion for our (1997) 110 defender and have some ideas of how I'd like to control it but my auto electric knowledge is poor and I was wondering if anyone could help? I've contacted a few auto electricians and no one wants the job.I have bought a stack pro water temp gauge which can be programmed to act as a switch once a certain temp is reached:52mm Auxiliary Gauges: Pro-Control - http://www.stackltd.com/instruments_pro_control.htmlAnd an on (veg) / off (diesel) / on (purge) 'master' carling switchIt's a twin tank system so start on diesel and once the water (engine) temp gauge reaches 70c the engine switches to veg oil.A minute or so before the journey's end we will switch to 'purge' and diesel will be drawn from the diesel tank but the unused fuel will be returned to veg tank to clear the lines of veg oil ready for the next start up.There are 3 x 3 way solenoid valves and a 12v diesel pump (veg oil is pumped via a mechanical pump and will always be in operation).On / Veg mode: 1, 2 and 3 and diesel pump is powered = veg oil drawn from and returned to veg tank in its own loop and diesel is drawn from diesel tank and used to run vehicle. Once stack pro water temp gauge reaches 70c: 1, 2 and 3 and diesel pump become unpowered = veg oil drawn from and returned to veg oil tank (engine now running on veg oil).Off / Diesel mode: 1, 2 and 3 and diesel pump are powered = diesel drawn from and returned to diesel tank.Purge mode: 1 and 2 are powered, 3 is unpowered = diesel is drawn from diesel tank and returned to veg tank.Although diesel mode is activated in the carling switch off position the solenoid will be powered as the vehicle will be in veg mode most of the time and will use less battery power this way.

Great - that's cleared it up thanks

yeah exactly It can't need a pump which delivers 782 psi can it?! Most pumps i'm looking at are in the 4-7 p.s.i band which made me think the figures are just written the wrong around because 56 p.s.i = 4 kgf/cm2 but that can't be right either as it means 56 p.s.i rated lift pump? Im confused....

Hi all, I'm trying to find out the spec of the oem fuel lift pump on a 300tdi defender 110 as I'm replacing it with a 12v pump. In the Defender Manual it says that the pressure is 42 - 55 Kgf/cm2 (3 - 4lbf/in2) but that can't be right as 1 kgf/cm2 = 14 p.s.i right? Does anyone know the correct figures? Cheers

Can anyone recommend a U.K. based auto electrician? I need help designing a custom loom in a defender 110. (Have tried auto sparks but they only make and won't help design). I know what I want to do but my electrical knowledge is poor and need help to realise it.

Don't happen to have a part number for this do you? Cheers!

Chap at bridgwater seemed well informed when I enquired about defenders. Regards using carling switches instead of stalks he told me: "The AP500 system has the ability to 'learn' different switches if they are resistive. If the switches have 1 wire per switch, it may not be possible. If you decided to use another switch, we recommend that you purchase a CM35, set the system up and test it using the CM35 and then try the other control. If all is well, return the CM35 to us for a credit. It is possible to use individual switches but you would probably need additional electronics to interface with the AP500 control unit". Any electronic pros fancy explaining how that might work?

Just found another kit called the AP500 which is a mechanical cable servo http://www.bridgwater-electronics.co.uk/cruise-control-kits/c51 £270 including Vat, delivery and CM35 stalk

Nice one ta - just found his/her fitting guide. Does anyone know how/if I could reliably use carling switches instead of the switch that comes with the aftermarket kit? An off / on and a momentary (speed increase and set) / off / momentary (speed decrease and resume) for example

Hi all, Can't seem to find a recent enough thread on this to know what's possible.... I have a 97 defender 300tdi with a TD5 binnacle (and gauges) and was wondering what's possible regards fitting a cruise control kit - before I delve into the world of after market kits I wanted to know for sure that I couldn't make a cruise control kit from a TD5 work? Am I right in thinking that it relies on an ECU or can it be made to work without? cheers

I'm trying to get to grips with designing a veg oil twin tank conversion for my 300tdi Defender and am trying to study up. I wanted some feedback on whether the following would solve the issues regarding fuel pump types and configuration? From reading other forum posts I: Would rather not use original mech lift pump for both fuels because the veg oil heater / filter need to go before the pump (so diesel isn't heated and to enable the use of separate filters for each fuel) and there would be negative pressure on the seals which isn't ideal. Would rather not use electric pump for both because decent ones are quite expensive and mech pump seems tried and tested for veg oil. Would like to pre heat the veg oil for initial flow at switch over from diesel to veg. Within that in mind.... In diesel start up mode: 12v fuel pump pushes diesel through sedimentor, filter, solenoid, injection pump and returns to diesel tank. Veg oil is simultaneously pumped via original mech pump through filter, heater and returned to veg oil tank in it's own loop created by solenoid 1. In veg mode: Veg oil is pumped as above but allowed through solenoid 1 and 2 to injection pump and returns to veg oil tank. Purge mode: as per diesel start up mode but diesel is returned to veg oil tank. This means that the mech pump never dead heads and is able to push through filters (and therefore no neg pressure on seals) with the added benefit that the veg oil is heated via the heat exchanger whilst engine starts and warms on diesel. I want to know if i'm missing something which is perhaps why this hasn't been suggested before.

Thanks for that. Great stuff. In case it's of any use to anyone I mocked up a carling switch actuator for an on (veg) / off (diesel) / on (purge) switch body. Mud made it up (laser etched type) for a few quid. Anyone welcome to use it.

I'm chasing my tail a bit. My understanding is: Veg oil temp only needs to be warm enough to flow / keep strain on pumps to a minimum. Engine temp is key to avoid incomplete veg oil combustion (piston ring gumming and sump oil contamination etc). So..... As long as engine (started and stopped on Diesel) is up to running temp and the veg oil is able to flow (40c and above) then the system is as good as can be? If the above is true, the creases i'd like help with ironing out are: How to get the veg oil to 40c+ at point of initial switch over from diesel - veg needs heating in / just before / just after tank right? Or a heat exchanger on the veg return to hasten the warming up process perhaps? Or is this a non issue i'm trying to solve? Which order to have veg oil loop components in (mechanical pump is a pusher so everything should follow it?) Should I go for: fuel tank - dedicated veg oil mechanical pump - heated filter (to avoid gumming of the filter) - heat exchanger - solenoid - injection pump? If the dedicated veg oil pump is mechanical how do I get it to idle when the engine is running on diesel. (I don't know a lot about how they work) Cheers all

That would heat the diesel (when in diesel mode) too - is that not an issue?