Builds Toyota '96 HDJ80 - Cummins 6BT conversion

Joined
May 4, 2014
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Costa Rica
Hi Mudders,

Some of you guys know me from my previous posts:
Rebuilt 1HD-T engine blowby when hot
1HDT Camshaft problem
Smoky 1HDT - Injection related

After a lot of headaches and tons of money I gave up on the 1HDT, looks like the engine is cursed or something. Last time I replaced almost EVERYTHING and got driven for 3 months and dead again, it has good compression but looks like the injection pump is bad, I might get a new IP later but for now I am just afraid throwing more money at it with no good results. Additional to this I have been aiming for 300HP out of it and thats kind of risky and expensive.

I ended up wanting to replace the engine for something else, something that can achieve 300HP easily without sacrificing too much reliability and money, well I hadnt to think a lot we all know that the Cummins 6BT is just the perfect fit for what I want.
I am creating this post to help other people who plan to make this conversion on a Land Cruiser (mounts, adapters, fans, sensors, etc). I will remain stock all I can, I will use my H151F behind the motor.

2/Feb/2019 - Towed the 6BT with the BJ40.
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This engine came out of a '98 Thomas School Bus, the owner removed the air pump for me.

14/Feb/2019 - Painted - Yellow Caterpillar.


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Updates will be happening along the conversion.
 

Mr Cimarron

DRIVE, BREAK, FIX, REPEAT
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Do you guys have many vehicles with 6BTs down there besides schools buses? Didn’t even know the buses down there had them. I think I saw two full size American trucks when I was visiting.
 
Joined
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Messages
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Do you guys have many vehicles with 6BTs down there besides schools buses? Didn’t even know the buses down there had them. I think I saw two full size American trucks when I was visiting.
Besides buses, you can find many 2nd gen Dodge RAMs with the motor.
It is easier to get it from a Bus because we have law which states that Buses cannot circulate for more than 20 years, that is why mine is a '98. You can find lot of american trucks in here, most of them used for work.
 
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Mr Cimarron

DRIVE, BREAK, FIX, REPEAT
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I have a similar bus engine that is going into my 75. The throttle control is the same as you have which is different than the ones that came in trucks. Hoping it work without modification as its a few hundred dollars for a used throttle assembly.
Wish I had your dip stick as mine is literally 6' long.
 

roscoFJ73

 
 
Joined
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Perth Western Australia
I think once you start using the power of the Cummins , the torque will destroy the H151. Engines are not cursed, it's how it's repaired or treated . It's your vehicle, but personally I think its terrible swap. Too much weight on the front end combined with excessive noise and possible vibration. Most of them seem to be up or sale within 12 months
 

Mr Cimarron

DRIVE, BREAK, FIX, REPEAT
SILVER Star
Joined
Nov 8, 2011
Messages
4,957
Location
Cedar Valley, Texas
I think once you start using the power of the Cummins , the torque will destroy the H151. Engines are not cursed, it's how it's repaired or treated . It's your vehicle, but personally I think its terrible swap. Too much weight on the front end combined with excessive noise and possible vibration. Most of them seem to be up or sale within 12 months
I would agree with the weight issue. In 30K or so of having it I have replaced front shocks and all tie rod ends. But noise and vibration is really a non issue. The 4bt yes but the 6bt is smooth and not much louder than any other mechanical diesel in the 5.9 range. The 12V is actually the quietest of the 5.9’s as the 24v is much louder which is kinda weird to me that Cummins updated the engine and made it louder.
 
Joined
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Messages
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I agree with @Mr Cimarron . IMO the 4bt belongs in a stationary application only because of how rough it is and now awful it is in general. 6bt is much better. Smooth even, and I agree how it is quiet compared to the 24V. I also agree it’s heavy. I think the 80 axle is capable of handling it, but I imagine a lot of 6bt swaps will end up going for a D60 if they can afford it. 6bt-thumbs up. 4bt-...no.
 
Joined
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Messages
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I haven't start the project yet because of some personal things, I bought some stuff in the meantime.
The Flywheel and Housing that the engine has, belongs to an automatic Allison trans so I bought a Manual Flywheel and Housing:

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3 inch TJM coil springs, Iron Man Foam Cell shocks and OME caster corrector bushings (best combination ever?)

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Bought a Radio because mine was dead. I highly recommend this one I love it, its called Pumpkin. Check it out here

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I got the Power Steering Pump and Vacuum Pump from a Dodge:

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Some of the other stuff I bought was...
450mmx300mmx76mm Intercooler
Bigger Vacuum Reserve Canister
2 electric fans 12 inch for the radiator.

I should expect to start swapping the engine this next month.
The hard thing to do will be to adapt the Toyota AC to the 6BT :cautious:.

:cheers:
 
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Joined
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Messages
188
Location
Costa Rica
Update:

I made a size comparison and the 1HDT looks looks so small next to the 6BT.

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Took my 1HDT back home will work on it after all this.
We are working on small details on how to put the 6BT inside, we need to cut the cummins housing and leave it as a "Flanger" to adapt the Toyota's housing in there.
Cummins housing has 2 engine mounts which collide with the 80's firewall, so they need to be cut.
We will need to use the 4 bolts side engine mounts.
 
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