Page 1 of 1

gq petrol to diesel conversion

Posted: Sun May 24, 2009 8:08 am
by BeNoS
hey all im about to do a petrol to diesel conversion on my gq shortie, my main couple of questions is
1 my mav is an xlt, so it has the better instrument cluster which id like to retain, but the doner vehicle is only a povo pack with the basic intrument cluster. if i exchance the whole wiring harness will i be able to basically just plug on my original instrument cluster into the diesel wiring harness and everything work? or are the other sensors needed for the gauges not there from factory?
2 the donor diesel is a jap spec unit with an inline injecter pump, from my understanding all the patrols ive seen are the ve type rotory pump. would it be worth my while to swap injector pumps over(intention is to turbo soon after install) to either another gq pump or even a gu td42t pump? and any ideas of cost for this one.
3 is the fuel tanks the same and if so are the sender/intank units the same or will i need to swap them over?
any help on any of the questions is greatly appreciated.
thanks in advance
ben

Posted: Wed May 27, 2009 12:45 pm
by marko78
Hey there mate, I have actually done this conversion myself. Your guages should work fine, just strew them out of the petrol and into the diesel. I could not get the factor tacho to work as in the petrol it works of the dizzi and in the diesel there is a sensor that counts timing gears so i just ended up using an after market one. The other thing you will have to do is hook up the glow plugs, i used a start solienoid and put a push button switch in the dash. I can't really help you out with the injector pump as the only one i've seen was on an st33 which is out of a MK patrol, not the td4.2. I know a recon rotar pump is around $1800 dollars. Ah yeah you will also have to change the bellhousing witch just bolts strate onto the gearbox. The fuel tank is fine the only thing you will have to do is take the filler neck out and knock out the splash flap out so that you can get the bigger diesel fuel gun in. Hope this is a help to you, don't be shy to ask any more questions.

Posted: Wed May 27, 2009 7:43 pm
by BeNoS
ah thats the kind of reply i was looking for. did you swap the whole wiring harness over or just use the petrol one and convert it? and so the tacho doesnt work with the petrol cluster? did you get the oil pressure gauge to work or your car didnt have it originally? um did you have to swap over the fuel lines under the car or just left em? um bout all i can think of atm but im sure more will come to mind as i go along?
thanks heaps mate
cheers ben

Posted: Thu May 28, 2009 9:30 am
by marko78
hey mate, yeah you can just screw the oil pressure sensor out of the petrol and straight into the petrol engine and the guage will work fine. I used the petrol harness as i didn't have a diesel one but if you changed it over to the diesel harness you may be able to get the tacho to work. The guage cluster is the same the only thing differents is the red line on the tacho is a little lower on the diesel. The fuel lines will be fine, if i can remember rightly you will end up with a spare fuel line which just needs blocking of. The only other thing i would be looking at is to make sure that the engine you have is the 4.2td, not the 3.3liter st33 engine. Check the engine number and there should be td stamped after the number.

Cheers

Posted: Thu May 28, 2009 11:24 pm
by BeNoS
hey mate thanks again. i will see about the oil pressure sendor its not the end of the world if it doesnt work. aftermarket gauges are pretty easy to rig up anyway, and il have to look into the tacho. may be able to swap the motors in the cluster to get it to work or something i will look into it anyway. and yes its definately a td42 lol. so really although it seems a rather big job its not that hard just lots of little fiddly bits involved. and a bit of nutting out a few little issues as they arise.
thanks again for your help
cheers ben