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Hello from another continent! I am from Costa Rica, in central America.

I have been an Isuzu owner for some years now, I bought a beat up Amigo with the 2.6L gasoline engine (MU to most of you), and restored it to half decent conditions.

Now I have purchased a partially disassembled 4JB1-T. It is here that I need your help. I will paste what I wrote on a forum in the USA, which has much more limited knowledge of these engines.

Two weeks ago, I either did something stupid, or I scored a good deal, time will tell. I happened to come a across a cheap 4JB1 Turbo engine in one of my scrounging of the local classifieds. Now, cheap can be bad, or can be good.
This is what it looked like in the back off the LandCruiser on the way home.


And this is how it looks on the floor of the storage building at work.





Failed Gasket.



Head:

Now, the story behind this engine...

The fellow that I bought if off, is an older gentleman, stuck me as the honest sincere kind of guy, so I'll believe his story.

He had this in a 1992 Trooper, had it overhauled because it was tired. He spent a good lot of money on the overhaul.
When it was put back in the Trooper, he had trouble with having the coolant reservoir pressurize. He changed radiator cap, then the radiator, and the reservoir. In the end it was pressure from the cylinders leaking into the cooling system. The mechanic pulled the head.

Now, here is where it gets interesting.
The mechanics diagnostic was, that the wrong liners had been installed, and there was insufficient liner protrusion, to seal the headgasket properly, so rather than sinking more money into it, the poor man went a got a 4JG2.
Now, the manual states that the liners can be flush with the deck, or slightly projected, which these are. I haven't yet measured the exact projection. Furthermore, the fire rings on the failed gasket, show over-torque if anything.
Verdict?
Dunno!
Simply a botched head-gasket install?
Liners were not fully seated, and the head and gasket finished seating them, thus destroying the gasket?

I don't know.
Since the head had been checked, and it was not overheated since, and because the headgasket had visibly failed, I will probably skip sending the head off to be checked.


Now, since I wrote that, I have been examining further, and found lots of piston slop.
I can't for the life of me, get a Youtube video to embed, so here's the link
https://www.youtube.com/watch?v=u-74Sfy3sKs
I'll try to get some more pictures a bit later, but what is the recomendation? Go ahead and do a full rebuild if budget allows?

Thanks!

I see I may have posted this in the wrong subforum. Could the mods please put it in the proper place? Thanks!

Now moved to engine faults
I do note looking at the head gasket severe corrosion around some of the water holes. Did they reuse the old gasket when they rebuilt the engine? That would raise the question about how long ago this was rebuilt and how well? The head looks ok but its not always easy to tell.

Just looked at that video
A full dismantle is in order. Dont know yet what will be found but prepare for the worst
Just out of interest though the correct engine for a 92 trooper was a 4jg2 so a bit more info might be required

geeves wrote:Just looked at that video
A full dismantle is in order. Dont know yet what will be found but prepare for the worst
Just out of interest though the correct engine for a 92 trooper was a 4jg2 so a bit more info might be required
Thanks Geeves. I'm going to tear it apart as soon as I can for a full inspection. Right now I am beginning to wonder if the fabled rebuild ever happened, I kind of think it didn't. I was noticing the corrosion on the gasket too. There is no way the amount of wear on the cylinder walls, and the corrosion on the gasket, is going to happen on a recent overhaul. I have a feeling the mechanic stole the man's money and never rebuilt it, or the man invented the whole story.

Here is a close-up of the cylinder wall.


I will keep updating this as I disassemble.

As to this engine being in a Trooper. I was originally a V6 gasoline engine, this one was put in back in 2005 from what I can dig up from documents on the national vehicle registry.

much of a lip on the liner?

That looks like a factory chrome liner that has been honed. Its peeling at the top

jellis wrote:much of a lip on the liner?

No way to measure, but enough to easily feel with a finger.

geeves wrote:That looks like a factory chrome liner that has been honed. Its peeling at the top

You know, I never thought of that! I wondered how the crosshatching could be so clearly visible, and yet have so much wear at the top.

You can get rebuild kits from the likes of aliexpress relatively cheaply but before you do anything I would pull the engine apart and see what you really have