2L engine rebuild failed, compression loss (1 Viewer)

[Akenture]

Hey there fellas, my battle rig is an Land cruiser 70 series (LJ70) 1985, with a non-turbo 2L diesel engine 4-speed manual gearbox (G40)
since last year i'm restoring it, including the engine (Incredibly it had the original pistons from plant), due to the wear i decided to rebuild with alternative spare parts according to the catalog, reputable brands in my opinion. Before doing the rebuild the engine lost its compression considerably, was burned the oil and lost power.

The following parts was used to assembly the piston
Piston: Teikin 2L piston kit / 46240
Rings: TP Ring kit / 13011-54060 / according to reference
All the work was done on the liners according to the piston used

My problem became after 5 months(5000km), same problems of compression and oil burning, blowing out oil from dipstick so i decided to change the rings brand (probably some bad luck factory failed )
So i put some NPR Rings (13011-54060) and failed again
again for the last time I disassembled the entire engine with my trusted mechanic in search of the problem, we found excessive carbon on the top of the pistons, the pistons seems like the 1st TOP ring didn't work properly, we decided to measure the ring GAP passed the tolerance inside the cylinder and was it ok

please note this behavior of the rings on the pistons

I compared the ring sizes and the piston depth

one of my mechanic's diagnoses is to remove the dipstick while the engine is running, if the oil comes out of the oil dipstick, the engine it's lossing compression and there's a problem in the combustion chamber

 

[Akenture]

I decided to try the same rings on another brand of pistons and the error was always the same, so instead of changing rings I decided to change the pistons to ALFIN version (TEIKIN), but this time using TP rings

The truth is that I have no idea what the error would be, if you could help me or if someone had the same problem
the engine keeps losing the power and blow up oil through dipstick.
an oil burn on a long drive can be disastrous for the rest of the engine

Greetings from Nicaragua

 

[RufusTheDufus]

Did you install new cylinder liners or just hone the originals?

 

[Akenture]

I put new cylinder liners, even when I open the engine it still had the pattern on the walls

 

[Akenture]

bump

 

[lacalvette]

What about cylinder head/ valve/ injector?

 

[Akenture]

New cylinder head, included all brand new valves and valve guides. I have checked the injection pump, but not the injectors. if i solve this oil problem i will.
this engine will gonna give me a headache

 

[lacalvette]

Head gasket?

 

[Akenture]

junta de cabeza?

Yes i rebuilt the whole engine with new parts except the injectors
i heard before the problem of cylinder head cracks of this engine (that's why i changed the cylinder head)

2LT cylinder head cross cut, the reason it cracks and fails

As some of you know I've recently made the mistake of acquiring a 2LT for my swap. After endless nightmare failures with this engine I got pissed off and threw the cracked head onto the bandsaw to see why they suck. The cooling chamber that runs between the intake and exhaust valves, at it's...

forum.ih8mud.com

but never this problem with the after market pistons, in fact I had never had a similar problem rebuilding an engine (3L and 2H engines still run perfectly)
That's why I'm seriously thinking of spending time and money..

 

[lacalvette]

liner were semi-finish or finish? Some finish liner can be chrome plated which aren’t compatible with some rings

Did you take a compression reading, leak down test?

Did you make sure all clearance were good with these aftermarket piston, including top piston to bloc surface.
Was the bloc check for distorsion