1HZ rebuild (1 Viewer)

[60/40GUY]

I'm rebuilding a 1HZ motor. Can I reuse the head bolts? Main bearing bolts? And the connecting rod bolts.

Also is there any particular areas in on the 1HZ that needs "special" attention? I am planning to add a turbo at some point. I can use any pointer you can give me. This is my first 1HZ rebuild.

Thanks

Frank

 

[roscoFJ73]

No,you need all new torque bolts,maybe they come with a rebuild kit.
Im also doing a 1HZ rebuild as funds become available so I will be following you
I may just take it to a rebuilder and let them do the internals and I will bolt on the outside stuff.
If you want full power you must have a good fuel pump otherwise the engine will never achieve it full potential.
What rebuild kit will you use?
Make sure you take pics of each stage as I am sure others will fing it extremely helpfull in the future

This should be in the diesel tech section

 

[60/40GUY]

I have not rounded up the parts for the rebuild yet. I am still in the tear down stage. The 1HZ is not very common in the US. My choice for parts will be limited. That is one reason I was looking at what I can reuse. The motor is from and old mine truck, so it is in tuff shape on the outside. But the inside surfaces along with the bearing journals look really good. When I get it all tore down I'll take it to a machinist to see how it measures up. That may dictate which "kit" I use.

Thanks for the input. I'll post pics of the progress. Curently I'm having one heck of a time with the bolt on the crankshaft pully.

Frank

 

[roscoFJ73]

I have not rounded up the parts for the rebuild yet. I am still in the tear down stage. The 1HZ is not very common in the US. My choice for parts will be limited. That is one reason I was looking at what I can reuse. The motor is from and old mine truck, so it is in tuff shape on the outside. But the inside surfaces along with the bearing journals look really good. When I get it all tore down I'll take it to a machinist to see how it measures up. That may dictate which "kit" I use.

Thanks for the input. I'll post pics of the progress. Curently I'm having one heck of a time with the bolt on the crankshaft pully.

Frank

The rebuild kits start at about $1100 AUD or $900 US + freight.
Thats not bad considering it includes pistons rings bearing seals gaskets and maybe the torque bolts.
With the engine machined and a kit you should get a 250000 miles minimum.

The bolt on the crank pulley,yes I had fun with that but the fuel pump was worse.
I made a 3ft spanner that bolted to the #2 crank pulley to stop the engine turning and rested it on the ground.
Then I used 2 1/2 ft bar with a 3/4" drive and socket on the bolt which I stood on.
Ive done it on twice on 1HZs and both times it worked like a charm.

One thing to remember when reassembling is to put the fuel pump on before the alloy cover at the front,in affect you build the pump into the motor.
The engine rebuilder and fuel pump shop were both adamant about that method.
My spanner pic
I have lots a 1HZ pics if you need any.Just PM me you email

 

[mac]

I used a gun w/ a 650ft/lb rating to remove the crank pulley on my 1HDT. Like butta'!

 

[60/40GUY]

Mac, I had my IR air wrench on the bolt for 10 min. with no luck . The wrench is rated at 600 ft/lbs. I took the block to a truck shop and they zipped it right off . Now I'm back in the saddle again.

RoscoFJ73, Thanks for the info on rebuild kits. I may be hitting you up on more info later. Can you get rebuilt injection pumps? Are they reliable? And how much? I heard new pumps are like $1500US . Is that true? How about rebuilt injectors? Or are there good, reliable and less expensive replacements?

Thanks

Frank

 

[roscoFJ73]

Mac, I had my IR air wrench on the bolt for 10 min. with no luck . The wrench is rated at 600 ft/lbs. I took the block to a truck shop and they zipped it right off . Now I'm back in the saddle again.

RoscoFJ73, Thanks for the info on rebuild kits. I may be hitting you up on more info later. Can you get rebuilt injection pumps? Are they reliable? And how much? I heard new pumps are like $1500US . Is that true? How about rebuilt injectors? Or are there good, reliable and less expensive replacements?

Thanks

Frank

Pumps are expensive,$1500USD new is not bad.The turbo pumps can be 3 times that new
A rebuild starts at about $500AUD
Australian diesel shops do the 1HZ pumps as their bread and butter.
The 2 shops I use normally have 5-10 1HZ pumps being fixed for the mines as well as a few hilux ect
They usually warranty their work for 12 months ,but of course if your o/seas that doesnt mean much.
However ,the diesel shops are reliable and are bench tested as part of the service.
I would be wary of used pumps unless they have been tested.
Used pump work fine when cold but when warm they lose pressure.most noticeably at highway speeds when you are trying to overtake but there is nothing left.
Rebuilt injectors are about $60AUD each.They are designed to be rebuilt many times by just replacing the nozzle bodies
Its the postage thats the killer
There is definately no el cheapo alternatives to quality fuel injection.
The inside of a pump is almost like a swiss watch
The chinese are trying to muscle in but its rubbish

 

[60/40GUY]

Just a little update. Most of the motor part are at the machine shop getting measured up. I ran into some issues with corosion on the block and a cover. I am going to have the machine shop clean the parts up and then see if it can be welded. I don't think it will be an issue because the holes are not in a stress area.

ROSCOFJ73- How did you remove the gear off the injector pump? Can you use heat? Or will that screw up the injector pump? I keep bending the bolts that screw into the gear.

Also how did you remove the tube from the thermastat housing which is in the block? The Gregory's manual sucks compared to the 2F FSM from Toyota. I couldn't find a 1HZ FSM. Is there such a thing?

Thanks again.

Frank

 

[brownbear]

How about try an injection shop near by for your injection pump rebuild. I know my local shop(Prince George) has done work to Denso. As they knew quite a bit when I called.

 

[roscoFJ73]

ROSCOFJ73- How did you remove the gear off the injector pump? Can you use heat? Or will that screw up the injector pump? I keep bending the bolts that screw into the gear.

Also how did you remove the tube from the thermastat housing which is in the block? The Gregory's manual sucks compared to the 2F FSM from Toyota. I couldn't find a 1HZ FSM. Is there such a thing?

Thanks again.

Frank

It took me 2-3 days to get the pump off I hired a puller from my parts shop and it kept bending bolts so I bought some more and eventually it come with an almighty crack.
Later on when I told the hire shop they said that when the bolts are beginning to strain give the puller a whack with a hammer.
Probably the tightest fitting part on any landcruiser so you know it cant get any tougher
I would not use heat.

Ive been using Gregoriys for 20+ years and they are an aquired taste but best used in conjunction with the FSM and there is a FSM that covers 1HZ,1HD T ect.
The FSM is more 1HDT inclined so I use the gregorys for the pics.

The heater tube can be banged out once the manifold is off.It will also swivel around The end inside the housing is slightly cone shaped that is bashed in like a welch plug.
It didnt come with the rebuild kit and I do not think it is reusable once disturbed.
I think it was about $80AUD but I cant be sure now

 

[VTCruiser]

has anyone considered sleeving these motors? it would seem like a good idea for furture work. just curious if there is a sleeving rebuild kit available. hopefully my rebuild is many throusand km's away.

 

[roscoFJ73]

has anyone considered sleeving these motors? it would seem like a good idea for furture work. just curious if there is a sleeving rebuild kit available. hopefully my rebuild is many throusand km's away.

Its common to resleeve these in oz if a cylinder bore is scored.
I guess someone like Geoff Walsh would have them.

 

[VTCruiser]

so are 1HZ's already sleeved or are they solid block?

 

[roscoFJ73]

so are 1HZ's already sleeved or are they solid block?

Solid block but they can still be sleeved by a machinest who knows what he is doing

 

[VTCruiser]

Solid block but they can still be sleeved by a machinest who knows what he is doing

right okay, that's what i thought. when you said "resleeve" it sounded like they might be sleeved from factory.

 

[mt72]

The rebuild kits start at about $1100 AUD or $900 US + freight.
Thats not bad considering it includes pistons rings bearing seals gaskets and maybe the torque bolts.
With the engine machined and a kit you should get a 250000 miles minimum.

The bolt on the crank pulley,yes I had fun with that but the fuel pump was worse.
I made a 3ft spanner that bolted to the #2 crank pulley to stop the engine turning and rested it on the ground.
Then I used 2 1/2 ft bar with a 3/4" drive and socket on the bolt which I stood on.
Ive done it on twice on 1HZs and both times it worked like a charm.

One thing to remember when reassembling is to put the fuel pump on before the alloy cover at the front,in affect you build the pump into the motor.
The engine rebuilder and fuel pump shop were both adamant about that method.
My spanner pic
I have lots a 1HZ pics if you need any.Just PM me you email
View attachment 95613

Hey Mate where can we find those rebuilding kit? I want to keep my 1HZ all motor I was wondering if anyone had put some oversize pistons and some more aggressive cams?

 

[roscoFJ73]

Engines Australia sell the high performance kits for the 1HZ. Most engines have 2 piston oversizes above the standard size. I would get some professional advice regarding cam profiles.

 

[mt72]

Engines Australia sell the high performance kits for the 1HZ. Most engines have 2 piston oversizes above the standard size. I would get some professional advice regarding cam profiles.

Hey Thanks, Rosco! I will add engine Australia to my list I wan to stay all motor for reliability and repair when doing our round the world overland trip but looking for a little more than stock engine!

 

[roscoFJ73]

IMO, a round the world trip needs a near stock engine. Rather than soup up a 1HZ, you would be better off getting a 1HD T .

 

[mt72]

IMO, a round the world trip needs a near stock engine. Rather than soup up a 1HZ, you would be better off getting a 1HD T .

Well not sure to follow your logic getting a turbo engine is more hazardous then rebuilding an all motor no bells and whistle one :/