HZJ73 Questions

[ForealBoreal]

I am trying to figure out a few things for my dad who might buy a HZJ73.

I know the 1HZ engine is a good reliable engine that is quite compareable to the 1hd-t.
from what i know you have to change the bottom end bearings. am i right?

Is the whole truck run on a 24 volt system or does it have the funny cross over system like the hdj81?
Are the headlights 24 volt?

whats somethings i should look out for on those trucks?

 

[Radd Cruisers]

The 1HZ is a great engine and takes to a turbo well, but it would be a good idea to add turbo pistons. the 1HZ is not direct injected and is not turbo charged. It does not produce any where near the power of the 1HDT.

The whole truck is 24Volts. Rust at the rear lower corners of where the doors open. The 1992 and later have rear seat belts, a roll bar, slightly nicer interior features. (I only have 1990 and 1992 - I haven't had a 1991 yet).

These units cost much more than a BJ7x series and are worth it. They are quieter, smoother, and are more refined in many subtle ways.

If you're in the area, I have 4 different ones here you can look at.

~John

I am trying to figure out a few things for my dad who might buy a HZJ73.

I know the 1HZ engine is a good reliable engine that is quite compareable to the 1hd-t.
from what i know you have to change the bottom end bearings. am i right?

Is the whole truck run on a 24 volt system or does it have the funny cross over system like the hdj81?
Are the headlights 24 volt?

whats somethings i should look out for on those trucks?

 

[Ron R]

I am trying to figure out a few things for my dad who might buy a HZJ73.

I know the 1HZ engine is a good reliable engine that is quite compareable to the 1hd-t.
from what i know you have to change the bottom end bearings. am i right?

As far as I know there is no known issue with the bottom-end bearings like the first HD-T. As a precaution you can replace them if you're unsure about the quality of servicing in the past.
My 1HZ has done 250k km's at the moment, with a lot of towing a heavy trailer and doing some off-roading including deserts. There is no indication that there is a problem with the bottom-end bearings. Service-interval (engine oil) is somewhere in between 5000 and 7500 k's depending on conditions, drivetrain is at 15000 to 25000 depending on conditions eventually shorter interval (deserttrip, water-crossings)

Is the whole truck run on a 24 volt system or does it have the funny cross over system like the hdj81?
Are the headlights 24 volt?

At least min is fully 24V (European version) don't know about other versions.

whats somethings i should look out for on those trucks?

Rust. Look at the edges of the front wings where they meet the wheel wells. The seams tend to rust.
Behind the door-opening and rear wheel well and rearend near wheelwell and rear lights.
When I bought my rig ( it was not new, about half a year old) I found standing water in those areas. These should be drained by small holes which tend to clogg. I used the tip of a tight-wrap to open up these holes that look like small gaps between the welded body parts. Later I drilled holes in the bottom of those areas and protected the blank metal resulting from the drilling with a good quality rust-prevention goo.
Frontwindow frame rust. The front window frames tend to rust from inside.
If you search this forum you'll find some related postings.

 

[crushers]

i will disagree with John on this one, running a turbo with factory stock pistons is fine.

the HZ is a VERY nice ride and comes with the H55F or the slush box. if you get the slushbox then budget for an extreme valve body right away as well as an aux tranny cooler.

i have nothing bad to say about the HZJ73 manual, it is one of the nicest rides around.

 

[Radd Cruisers]

i will disagree with John on this one, running a turbo with factory stock pistons is fine.

We're kinda' sorta' not disagreeing, I just said it's a good idea - certainly not needed.

It has been told to me by those with significantly more long-term working knowledge that the 1HZ with higher boost levels will erode the ring lands. Turbo pistons (aftermarket) for the 1HZ have steel ring land reinforcement.

When I add a turbo to one of mine, I'll probably forgo the pistons and keep the boost reasonable.


~John

 

[crushers]

light duty "disagreeing" as in "good idea but not something i would do".

if i was building a high horsepower, high boost 1HZ and had oodles of cash then i would look into it.

now, if erosion was to take place then wouldn't the erosion happen even without the boost?

 

[Clint79]

The 1hz can still pull good with no turbo ,had a situation were i had two dirtbikes and camping gear on the back of my 75 series blew the tranfercase left all the gear on my ute , put my 75 on the car trailer and my dads hzj75 towing the lot from wedge island which is around 120km from home it purred all the way home some hills were 3rd gear but didnt miss a beat or over heat, Good motor

 

[roscoFJ73]

if i was building a high horsepower, high boost 1HZ and had oodles of cash then i would look into it.
?

If you had "oodles of cash" ,why wouldnt you just buy a 1HD T or FT?

I tend to believe the 1HZ should be turboed with caution.
I think a mature person who understands whats happening can get some reliabilty from a turboed 1HZ,but if you sold them at the dealer new ,the warranty bill for melted pistons would be horrendous

Which is why Toyota used heavier pistons and a lower compression ratio in the factory turbo models

 

[crushers]

have you seen melted pistons?
what boost was the culprit running?
what fuel setting?

i DO NOT like HDT or any variant of it. i DO NOT like direct injection and that is why i would build the HZ up IF i had ooodles of cash. i don't have that cash so this diescussion i really mute anyway.

 

[prado t]

It has the weaker 8" front end, compared to a BJ7* . It is a good machine.

IDI SUCKS THE BIG ONE.

 

[crushers]

care to come play?

IDI SUCKS THE BIG ONE.

 

[roscoFJ73]

have you seen melted pistons?

pictures ,but you dont really need to see them to understand.

what boost was the culprit running?
what fuel setting?

I dont know,nor do I care,its irrelevant. Toyota built a dedicated turbo engine for a reason.

i DO NOT like HDT or any variant of it. i DO NOT like direct injection and that is why i would build the HZ

You have said many times you do not like them ,but you have never said why

up IF i had ooodles of cash. i don't have that cash so this diescussion i really mute anyway.

Well you are the one that brought it up

 

[crushers]

actually Rosco, yah i have said why many times...
i do not like the sensitive throttle
i do not like the fuel mileage (in my experience as well as a few others here in canada) the IDI gets better mileage than the DI.


as for melted pistons, yes what the idiot did to cause the failure IS relevant to the equaltion. if i take a HDT and over boost and over fuel excessivly then it too will die a painful death so if this is the case then turboing a 1HZ is no different.

Toyota also built a dedicated engine, the 2LTE and it was no roaring hell either. To say, Toyota built a dedicated engine makes the same amount of sense. Just because Toyota built it doesn't make it right.

if you like the HDT fine, that is your choice.

 

[roscoFJ73]

actually Rosco, yah i have said why many times...
i do not like the sensitive throttle

1st Ive heard of it and the one I drove never had that problem.

t like the fuel mileage (in my experience as well as a few others here in canada) the IDI gets better mileage than the DI.

I would have thought it too close to call.

melted pistons, yes what the idiot did to cause the failure IS relevant to the equaltion. if i take a HDT and over boost and over fuel excessivly then it too will die a painful death so if this is the case then turboing a 1HZ is no different.

Obviously over boosting and too much fuel will kill any diesel but a dedicated turbo engine will take the abuse for longer.
Its the long hills with a full load that can send the pyro temps sky high.
This is why I said the 1HZ T is more suited to mature owners who understand whats happening.

Toyota also built a dedicated engine, the 2LTE and it was no roaring hell either. To say, Toyota built a dedicated engine makes the same amount of sense. Just because Toyota built it doesn't make it right.

Thats a red herring. The 2LT had coolant flow problems in the head and was really a non turbo engine with a turbo added which actually proves my point.
Having `said that I was talking to someone the other day and his JDM Surf has 230000 klms and has never had the head off

 

[crushers]

<shrug>
what ever, it comes down to what a person likes and doesn't like. you like the "idea" the HDT is a better, stronger engine.
fine by me.

 

[Radd Cruisers]

The 1HZ and 1HDT are substantially the same engine much like the 2H and 12HT... the 1HZ is better in the bottom end torque, low speed torque and would be better in a manual transmission off-roader.

I don't think the 1HDT with an auto would wheel that badly, it's not as sensitive as the 12HT... which is a bit of a beast off-road with a manual trans.

If the HZJ73 was the project I was pursuing, it would get a turbo for sure....


~John

 

[prado t]

care to come play?

That was a post that should have said IDI sucks the big one( for me)

I should have remembered that there are some IDI lovers.

As for the sensitive throttle , I picked up a way way way: stiffer spring. I jigged it up to work with the throttle cam and then too the intake manifold. 500% improvement amazing what a $1.50 screen door spring can do. I will post a picture soon.
After the first day wheeling the BJ ,I new something had to be done. I really like the stiffer pedal Nite and Day difference.

As for the original question, If you are looking at an auto , double check it ie fluid colour and condition, and also the automatic hubs. The HZJ is slightly more refined than the BJ , also after 89 I think they were less prone to rust compared to the pre 90s

 

[ForealBoreal]

its a 91, 5 speed with factory lockers... pretty sick truck.

so the 1hz and the 1hdt have idi?

 

[Radd Cruisers]

its a 91, 5 speed with factory lockers... pretty sick truck.

so the 1hz and the 1hdt have idi?

No, the 1HZ is indirect, and the 1HDT is direct and turbo.

They are both really nice engines.


~John

 

[Psilosin]

Does the manual trans HZJ73 have a solid or dual mass flywheel?