Offroad-Express

lookn @ several engine options for my 89' LJ71 that has a 2LT stock , know that theeres the similar version of my cruiser that has a 1KZ-TE with auto , Have seen a few of these engines going cheap on trademe lately & what i have read here about gettn the injection pump modded for mechanical injection - maybe its a possibility .

Anyone had hassles with these engines ? what you think of them ?

Not sure you can convert to direct injection, these are a really good engine but they still crack heads so getting the heat away from them is worth the effort. There are also a couple of rubber plug's on the block that perish and will allow the radiator to empty (happend to 4 I know of) so inspect these and keep looking for water missing from the radiator when you have a look at the truck before your trip's.

Most likley the one you find will be out of a Highace van or similar and not have as much torque as the landcruiser one. Also the van ones have most accessories (alt etc) mounted lower, you could also look at the 3.1 turbo diesel Isusu motors if you want to move away from toyota.

Nice peppy engine with a broad torque band as needed for offroading. They really need the intercooler if you use your right foot.

Get rid of the EGR valves this increases the head temperature. They do crack heads and supposedly the new heads are a better design but that will cost $3k minimum to get fitted. Fit a 3" exhaust as well.

My engine has responded really well to porting the head, mostly on the short side radius in the exhaust ports.

Yes manual pumps are done regularly on these by Scott at Diesel Pumps ph 03 348 1132
cheers John

cheers for the info,

Do you know if they are all alloy ( Block & head ) or just alloy head ? are these motors OHC 16V or just 8 ? remember there was someone on here who bought a new head , had it cryogeniced , forgotten who that was . i reckn a good pocket port job would do wonders

Found this on Wikipedia >>

1KZ-T
The 1KZ-T is an early version of 1KZ-TE, 2982 cc, 4 cylinders, SOHC, 3 valve per cylinder turbo diesel engine. Bore is 96 mm and stroke is 103 mm, with a compression ratio of 21.2:1. Maximum output is 125 hp (93 kW) @ 3600 rpm and maximum torque is 29.3 kgf·m (287 N·m) @ 2000 rpm.

Used in KZJ71W, KZJ78W


1KZ-TE
The 1KZ-TE is a 3.0 L (2982 cc), 4 cylinders, SOHC, 3 valve per cylinder turbo diesel engine. Bore is 96 mm and stroke is 103 mm, with a compression ratio of 21.2:1. Maximum output is 130 hp (97 kW) @ 3600 rpm with maximum torque of 29.3 kgf·m (287 N·m) @ 2000 rpm. Redline is 4400 rpm. First produced in 1993, it is still used in new model vehicles today. 1KZ-TE also adopt the electronically controlled fuel injection, ETCS-i (Electronic Throttle Control System - intelligent) technology which is similar in basic construction to a modern gasoline injector, although utilizing considerably higher injection pressures, making it a very efficient engine.

Used in KZJ71W, KZJ78W, KZN160

The intercooler equipped version of the engine power up to maximum output of 145 hp (108 kW) [Aust. 130hp (96kW)] @ 3600 rpm and maximum torque of 35.0 kgf·m (343 N·m) @ 2000 rpm.

Used in KZJ90 (Prado, Colorado 3-door), KZJ95 (Prado, Colorado 5-door)


So i can run an aftermarket fuel only ECU ( Computer ) for this after all , wasn't sure how to trigger the injection pump , etc !

The Wiki is incorrect. Tis only 8 valves. Iron block and alloy head.

My porting has proved quite dramatic, On a straight near home that I drive most days, I enter over a bridge cornering at 100ks. At the other end 1.5 ks on I used to just get to 140ks. Now with re-coed injectors and ports modified but not valves, I get to 140ks after 0.6 km. I have also ported the long alloy pipe from the turbo, the semi spherical chambers either side of the throttle body and the inlet manifold. I also tig welded up and ported back to smooth, the EGR groove in the semi spherical chamber within the inlet manifold. Saw 150 ks tonight on another straight but the air was cold and therefore dense.

Talking to a mechanic a few weeks back about the new Hiluxes. They have a 1KD-TE motor, which he said was the same as the 1KZ-TE but with direct injection. If Toyota are still putting them in new vehicles they must be alright. He had seen a few 1KZ-TE heads crack, but it depends on how they are operated and maintained, same as most engines.

Heard also that new 2wd Hiluxes have difficulty getting off the mark quick as they light up very easily.

Saw 150 ks tonight on another straight

Jeez, have a wobble on at that speed?

rowinz wrote:

Saw 150 ks tonight on another straight

Jeez, have a wobble on at that speed?

Not at all, thats why I like my standard suspension. 31 BFG MT's at 40 psi and 8" rims help too.

Icedjohnno >>> got any pictures of the mods you did to the head , intakes , etc ? you get the head checked on a flowbench ? sounds like you have greater efficiency within the cylinders now - coool , what turbo are you running ?

All this time , i thought Wikipedia was accurate - bugger !

Sorry to look like a hi-jack artist here guys. Johnno, my daily driver is a Hiace Super Custom with 1KZ-TE and auto. Would this benefit from removal of the EGR valves and bigger exhaust? How easy are the valves to remove? I love this engine! Cheers, Andy.

are'nt the EGR valves like the little plastic things & hose's on top of the engine or are they vacuum ?

I have no idea, but I wouldn't have thought exhaust bits would be plastic? And a diesel needs a vacuum pump.............. but then I'm probably miles off

think EGR stands for "Exhuast Gas Recirculation" , my current 2LT has it , pipe coming off the wastegate exit around to the Intake manifold .

ah yes, the old Exhaust Gas Recirculation.......... bl**dy emissions rubbish

Hi, i recently did a head on a 1kz in a surf. Can confirm that yes, its a cast iron block, alloy head. Head was $1200 including getting the valve gear swapped over and lapped. It was an extra $300 to get the head installed, and had we know, would have happily paid that

The original head cracked between the pre-combustion chambers and the valves, and also between the valves on all cyclinders. The engine had been cooked about 3 years ago due to a un-noticed leak developing in the bottom tank of the radiator. According to the place we got the head from, its not so much theheat that gets them, its that the alloy gets porous over time alowing it to crack. Lots of differeing opinions on that one

We also found that some of the water galleries from the block to the head where blocked or partially blocked with rust scale. Also a contributing factor to head temperature.

In all, they are a good performing engine, and $1200 for a head aint that bad. I also believe mike got his new head for his surf cryo'd.

adventures_more wrote:Icedjohnno >>> got any pictures of the mods you did to the head , intakes , etc ? you get the head checked on a flowbench ? sounds like you have greater efficiency within the cylinders now - coool , what turbo are you running ?

All this time , i thought Wikipedia was accurate - bugger !

Yes I took a lot of pictures with the view to a thread on it. But in the middle of lots of work, both paid and played but mostly what will be a 9 month house shift, so no time at present.

My mates Flow-rig now lives in Wellington it was the first one in Chch years ago. So no I didnt flow test this one and this is not a race motor either. However I've been porting heads since I was 14 and have learnt a bit.

Still running the factory turbo although I have been shown where these are restrictive and what type to go to later on when I up the boost. I cant remember which Garret it is now thou, ah too much methanol for too long in this brain.

Never trust the internet, its full of useless rubbish. Always verify to get the good stuff, me included!

vando wrote:Sorry to look like a hi-jack artist here guys. Johnno, my daily driver is a Hiace Super Custom with 1KZ-TE and auto. Would this benefit from removal of the EGR valves and bigger exhaust? How easy are the valves to remove? I love this engine! Cheers, Andy.

The vans are the worst for bad heat flow out from the radiator. The next worst are the Surf’s and then the Prado’s.

I had a damn good radiator which proved fine when we went to clean the tubes out. Having pulled the top tank off, we replaced it as these plastic tanks are prone to crack with heat and time.

Definitely blank off the EGR valve. The simplest way to do this is to make a steel gasket that fits where the flanged tube mounts on the back of the EGR Valve, just behind the inlet manifold.
I regard this factory device as another way of shitting in your own nest! My inlet manifold was coated inside with about 5mm's of tar. It took a week of soaking in a 20l bucket of petrol and a lot of scrubbing with a big test-tube cleaning brush to remove it.

The bigger exhaust removes more heat from the engine quicker. 3" seems to be recommended although I haven’t done mine yet. I understand that the issue is the long term elevated exhaust gas temps especially if you are towing or working the turbo hard. It seems that the Japs don’t use trailers so no doubt mad kiwis weren't in their design brief!

Suggest you fit a remote trans cooler as well.
I know of a local logging contractor who has had 3 new heads fitted to one 4wd Hiace van in the previous year. This van is always heavily loaded and covered in mud. They have now fitted; a bigger exhaust, removed the aircon radiator, fitting a remote trans cooler, opening up the grill area and blanked off the EGR valve (all at differing stages on the previous heads except the air-con rad and the remote trans cooler which were done as the 3rd new head was fitted)

DB $300 to fit a head! There was about $2300 involved in that work on mine, thankfully reduced thru the services of Charlie Ash. I could have done it myself but my experience is all petrol based or racing derivitives of that and I simply did not have the time. I don't think you would get much of a job done for that having seen the work involved and the time too.

Thanks John, I really appreciate the information. My hiace has done just over 200k, and I feel its going every bit as well as when I bought it at about 100k. Uses no water and almost no oil between changes, maybe 5mm on the dip stick in 5000km. I've got something in the back of my mind tells me it's already got a remote trans cooler, but I'll sure check, and I'll have a poke around to see what i need for the EGR valve blanks. My background is aircraft engineering, I work at the jet engine shop at Chch airport, so diesels are like another world to me, but I fully understand what you mean about heat removal, and the bigger exhaust.
Cheers, Andy.

I paid for my head to be done in Queenstown, drive in drive out and that cost $2200 inc GST.

Thinking more about it, was really only $1800 + head to do the fitment as $500 was for the re-coed injectors. Seems that particular type of injector is expensive.

wjw wrote:I paid for my head to be done in Queenstown, drive in drive out and that cost $2200 inc GST.

What workshop?

Donny down Repco Boulevard.... but he did it on the cheap as I had alot of work done around that time

comin in late on this one, but would just isolating the vac hoses on the EGR valve prevent the valve from opening and therefore remain shut? This would require less fidling as the back of that valve is quite hidden. John you've obviously had a good look in there? Didn't you weld your inlet manifold up? What's happening with in manifold pressures when that valve is opening and closing and how does this relate to the electronics/ fuel delivery? I love the way the old 94 prado wagon goes but can't help thinking there's a few good little tricks to make em better.Wish my safari went that well!

carver65 wrote:comin in late on this one, but would just isolating the vac hoses on the EGR valve prevent the valve from opening and therefore remain shut?

yes, but you run the risk ofthe EGR valve being stuck open which is a fairly common problem.

O.K. so I'm thinking a small blanking plate at the ex manifold is the next easiest option. Or is it better to go between the valve and the inlet manifold? After these what else ? I'm going to have a cooler ,cleaner intake charge with better economy/performance just like that with no downsides?

blocking both end is preferable. blocking exhaust is good as your not heating the end of manifold or have problem with leaking egr pipe. blocking inlet side is good as it reduces unneeded space in the intake system (less volume to fil = less lag).

the hard part with 1kz-te is disabling the egr butterfly setup in the intake. i'm not 100% sure on the setup so you will need to sit down an work out what part does what. ideally you do not want any blockage while the motor is running but still have the butterfly close fully when you turn the motor off.
if i remeber correctly its a dual butterfly, one part run by a solnoid and the rest is via throttle cable. you can disable the solinoid easy enough. making it work just for shutdown i do not know.

the reason for all the hassle of disabling the butterfly is it will block air flow and you will get vaccum in the manifold. the lack of air gives you less effective compression which is not to good on a motor that requires compression to ignite the fuel. it will actually still run, but they go so much better without any restriction in the intake.

Sound as if ,from what you're saying, that the best bet is to get right into it like Icedjonno and rebuild the inlet manifold, completely doing away with the whole thing. But I still wonder what that does to the engine management when its not geting a signal from a piece of the induction/exhaust. What about blocking the ex manifold and routing that existing pipe to
either the air cleaner ( low pressure ),to give the valve clean air supply or back to the inlet side downstream of the turbo ( higher pressure )?In effect creating a some what useless loop on the inlet side, but with clean air.

carver65 wrote:Sound as if ,from what you're saying, that the best bet is to get right into it like Icedjonno and rebuild the inlet manifold, completely doing away with the whole thing. But I still wonder what that does to the engine management when its not geting a signal from a piece of the induction/exhaust. What about blocking the ex manifold and routing that existing pipe to
either the air cleaner ( low pressure ),to give the valve clean air supply or back to the inlet side downstream of the turbo ( higher pressure )?In effect creating a some what useless loop on the inlet side, but with clean air.

????? errr......what

you could get rid of the whole butterfly assembly except you wil need to rerig the TPS to the accelerator cable.

the egr pipe, once blocked at both ends can be thrown away comletly.

carver65 wrote:What about blocking the ex manifold and routing that existing pipe to
either the air cleaner ( low pressure ),to give the valve clean air supply or back to the inlet side downstream of the turbo ( higher pressure )?In effect creating a some what useless loop on the inlet side, but with clean air.

You might be on to something. It'd be a lot more work than simply disabling the system though.

routing egr pipe to pre turbo will just make things way worse as you will be bleeding off boost back to the air intake. ie like a BOV thats stuck open.

far easier to block the crap off and disable the butterfly.