Modding the head of a GQ for better cooling?

[Ezookiel]

I've just spent an absolute fortune getting my engine replaced with a recoed one at East coast 4wd, had them pull off a dud turbo, and am having it sent from there to GCG turbos to have them replace the dud turbo with a new schwitzer turbo, and even totally splurged and am getting them to add an intercooler.
When you go to that sort of expense to make sure your engine works and no longer overheats, you may as well "the throw the cat another goldfish" so to speak, and get the head mod done where they run water into the top of the head.
I have no idea what the mod is actually called, and so am having trouble finding out information about it. But I'm pretty sure someone here will know what I'm talking about and be able to give me some more details.

What is the mod.
What's it involve.
What do they actually do.
How much should it cost.
Does it work
Is it worth doing,
And does it raise any other problems, it sounds like it's some pretty major changes to the way water flows around the place.

Thanks in advance for any help or advice you can supply.

[blackmav]

Has this new donk got warrantee...........Dont mess with it.
Drive it.
GET A PYRO, and new water temp guage.

And I thought it was the petrol motors on gas that you would do this to, not the deisels.

[Ezookiel]

Ah, ok, once I stopped looking for TD42 and looked for TB42, and once I stopped looking for diesel, I found a very small thread.
http://www.outerlimits4x4.com/phpBB2/vi ... ss+octopus
It doesn't tell me very much though.
So would still love some more information, other than the fact that it involves a brass octopus ?

[Brendan-s]

What you're asking about is called diesel water injection. Hit google for that term for some general info...

[Ezookiel]

Thanks BlackMav,
Good point about the warranty, and that thread I finally found does seem to imply it's for gas converted petrol engines.
I am just determined to get this stupid car right, whatever it takes, and want to make absolutely positively CERTAIN that I don't keep blowing gaskets and engines. I can't afford this process again, so thought I might consider it, but it may be looking like I can put the money I'd have used to do the job, into doing other niceties instead. I sure can't afford to risk the warranty, so certainly wouldn't consider it now for at least six months till the warranty on the recoed donk runs out, if at all.

[Hoonz]

you've had this problem for a while now ... would have been cheaper for you to throw in a LS1 almost

[Ezookiel]

Well, some little turd, has put all over the net, a million copies of a video called "diesel water injection" that then wreaks havoc with your browser, and opens up all sorts of pages that try to install malware removal tools.
Very nice of them.
Trying to weed them out makes searching the net so much harder. Little pricks.

[weeman]

Hey mate,

I think i know what your talking about alot of the comp diesel down here in melbourne and some in WA have had this done.

What i think it is (DanielS) off here can explain in more detail. Is that you drill into your cylinder head and you can run a coolant through the head and drop down your temps.

Maybe for your application i.e. non comp use it may not be of value, i would be more looking at your current setup enuring you have a decent intercooler setup including pipe work, air box (standard nissan is average) maybe a large snorkle to get more in there.. And most importanly a pyro to monitor your temperatures...

[Hoonz]

can u list up exactally what you have done again?
fitted guages etc? some thing doesn't sound right

[Ezookiel]

The Pyro is being done the moment it gets home.
I'd prefer it done in Sydney before the drive home, but am finding it hard enough to move the vehicle around up there when I'm down here, let alone find someone up there to put one in for me. Neither of the places doing the two major jobs (engine and turbo) do one, let me know, I'd be very interested.

[GQ TROL]

The design of the head allows air pockets to remain at the top instead of being bled out through the thermstat. The coolant rail gives you a higher bleed point and therefore able to get air pockets out.

Drill and tap a hole next to each injector, put a 2-3" riser on each one and connect them up and connect the rail into the top rad hose. Having a grope around the intake ports will show you best place to locate the holes.

DanielS that Weeman refered to sent me pics of his setup, and we just copied.

[AFeral]

seen some of the ontrack built cars from melbourne run this set up try contacting Ontrack they might know.

[DanielS]

G'day ezookiel,

I have done the mod you asking about and I refer to it as a coolant bypass.

As stated by Weeman and Mitch, you have to drill and tap a 1/8 bspt hole into the head between the injector and glow plug for each pot, then connect them to a fuel injection rail or simular and connect into the coolant return - radiator hose.

If your not to keen on this I, but feel its needed, I would look into pushing the right rear core plug out of the back of the head, drill and weld a hose fitting in it and replace. then hook this into the coolant return. This would elp balance the block temp. If you still want to go with running a hose out of each pot, you can feel the pre co chamber and area that you need to drill into once the core plug is removed.

But as Weeman said, this has been done to comp diesel trucks running 2x more fuel than standard. With a good HD radiator and good cooling system, it should be more that able to cool your engine.

Mitch, hows your truck going??


Regards

Daniels