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Newbie with some questions ;)

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G'day Fellas. Just brand new here today. Have built and maintained a small fleet of L Series over the last 5 years and have just put together my first '86 turbo (from various doner cars). Trouble is its running hotter than Im comfortable with in this summer weather we're having down here..

Have done all the usual checks: HG's (no coolant loss, no CO2), flushed, new rad, w/pump, timing ok but suspect the turbo is cooking its water as it idles forever at good temp but heats up quickly when the turbo's in use and recovers when you back off..


So I've become interested in trying to increase the cooling capacity of this and have some questions if anyone would be kind enough to share:


1. Has anybody successfully shoe-horned a Brumby (Brat) radiator into an L series?

2. Which way does the water flow thru the turbo? (Out the top back to the thermostat housing?).

3.  Which way does the oil flow thru the turbo?

4. I saw some photos here of a vortex (XT) which seemed to have its bonnet scoop plumbed to a funnel focused on the turbo. Would this be right and did the factory do it for more cooling do you think?


Thinking of putting some extra coolers in line with these but open to any suggestions.


With thanks, (only 1500 pages of topics left to read) Bert.


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First advice check catalytic converter for obstruction. Next if you really want to make it run cooler I got two words for you, custom parts. I got quoted only $350 for a custom radiator much thicker and more surface area than my stock gl. Adding a small extra cooler on the turbo water lines might help, but a high cost is still involved

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If you search a bit on here you should find some more info about the engine and cooling system.

Several problems with the engine have been listed and I'll try to fill you in on that a bit.

1. Engine wasn't designed to allow maximum cooing between the halves so the pass side always ran a bit hotter than the driver side.

Not much you can do about that.

2. Turbo on this engine is fed coolant from the passengers head, so the coolant is already hotter that the rest of the engine when it goes into the turbo.

A couple things you can do about this. I found that you can take the coolant feed pipe off the pass. head and install it onto the drivers head with a little bending of the pipe to get around everything in that area (egr, steering etc....).

So then the coolant is going into the turbo a little cooler, or about the same as the temp of the engine. But the water flow is reversed..... Never tried to get it set up for the normal direction of cooling.

Mine did run a bit cooler but still ran hot when pushed.

I also tried adding in a reservoir after the coolant left the head to allow the water to cool down a bit more before it got to the turbo. Also adds some capacity to the whole system. That helps also but still not enough for my tastes.

Wire the cooling fans to always run. Jump across the connector for the temp sensor on the Radiator.


Make sure the O2 sensor and cat are working and you aren't running lean.


I ran one of these in the interstate up here in Idaho during the summer and the turbo so so hot that it ignited the vapors from the vapor canister and caused all of the threads for the bolts that connect the 2 halves of the block together to pull out and had to be heli-coiled.


Water flows out the bottom of the head threw the turbo and then to the thermostat housing.

Oil flows out the head through the pipe then drains threw rubber hose back into the head threw gravity.



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Thanks fellas.

I'll post back when Ive got some experiment results..


Still interested to know if anyone has managed to fit a brumby (brat) radiator into an L series tho..anyone?


Cheers, Bert.

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G'day. Thanks again. Fitted one of these in between the turbo water output and its return to the thermostat housing:




S'posed to be an oil cooler but I changed the fittings to 1/2" (high flow - no step) and mounted it under the radiator. Also took the long ways round and it definitely sheds a lot of heat (much hotter on the turbo side of the cooler). 


Seems to have done the trick for now as its autumn (24C) and not summer (34C). Will see how it goes when it warms up again.


On a related note, Hush, I was interested to hear about the water flow directions out of the bottom head ports: Do you reckon I would get flow between the two ports if the pass one is out and you say the drivers one is reversed? Im interested in putting one of these coolers on my wifes MPFI to better cool when shes using the aircon and this would add cooling and capacity. What do we reckon?


Cheers, Bert.

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G'day mate,


Best thing you can do for your turbo is exactly what you've done for it.  I would've mounted this behind the thermo fans so you're not adding hot air in front of the radiator.


Another thing to look into for both your vehicles is a copper radiator.  A good unit will cost you money but will get the job done well.  I'm now running a Nissan Pulsar N13 radiator with my EJ22 in the L series (new mount holes at the bottom drilled in the rad support panel and the upper panel folded up a little to slip the radiator under).  Works well but I'm still looking for a bit more cooling in the summer offroading similar to what you are.  On road and around town I have no issues.  Lower rad hose would be the bit to work out on the EA82 setup as it only points straight out at the engine rather than up on a 45* angle.


Years ago I fitted a brumby radiator as a temp setup.  It didn't fit well and wasn't a pretty install at all.


Creating a larger bash plate, or air dam under the car between the rad support panel and the engine crossmember can increase the negative air pressure in the engine bay which will naturally help with pulling air through the radiator.  On our last trip across the Nullarbor in the middel of summer we resorted to using a grill from a truck that we happened to find on the side of the road to create this air dam.  Was awesome, but did look a little bit odd if you noticed it:




^ That was loads better than my mad max setup on the trip over...


Also, what thermostat are you running?  If a generic after market there's a "high flow" option.  I'd recommend using this unit if not using a genuine thermostat.  The MPFI shouldn't be overheating with the AC on unless there's some other issue lurking/waiting to rear its ugly head.




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just as a double check since you said you put it together from multiple places.  you could be leaning out under boost. 


did you pull the motor as a whole or did you put it together?  temps can go up when your comp is too high (if you used non turbo pistons), or if your turbo is running higher boost than normal.  if you have played around with the compression or boost levels you may need a reflash or independent fuel system to add back in some fuel to cool it. 


also the injectors are rated for barely the amount of stock horsepower (at least over here) so you may think about upgrading them when the time comes.  I seem to remember they were a standard style used by many cars so people used to just use stock ones from different cars that were rated higher.  Ford Thunderbird?  cant remember exactly but this kind of thing was discussed a long time ago when people were still modding out the 82's.

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