Dirty Coolant

[jimlevin]

Those are also the Optimizer heads. You can see the Navistar "endless roads" symbol in the casting:

Have a look at your glow plug tips also. Burning (IE: melting) or swelling is good reason to swap them out now. Much easier than when the engine is assembled.

So you're thinking this engine is the optimizer?

 

[great white]

So you're thinking this engine is the optimizer?

Yup, your date code also confirms it.

The clincher would be this in the intake valley:

The Navistar "endless road" symbol. Oft referred to as the "double diamond", the "diamond" or "double triangle"....what it really is is the International trucks endless road symbol:

Navistar owns the International name and the engine foundry, so the blocks are referred to as Navistar blocks. GEP is owned by AMG but neither havea foundry to cast blocks so it was contacted out to Navistar for the finished engine and head castings. GEP then assembles the engine.

The bottom line in this is that your engine is a GEP optimizer 6500.

04 26 H is Apr 26 2001

GEP started their numbering with H which stands for 2001.

 

[greenmeanh1]

It sure seems to indicate 2008 gep optimizer by all the stamps. I believe thar is the letter N in the casting which stands for the year.

 

[jimlevin]

Wow, finally some good news...geez!

Here is a couple more shots...there's diamonds in that there valley boys! Date code on block.

Yup, your date code also confirms it.

The clincher would be this in the intake valley:

The Navistar "endless road" symbol. Oft referred to as the "double diamond", the "diamond" or "double triangle"....what it really is is the International trucks endless road symbol:

Navistar owns the International name and the engine foundry, so the blocks are referred to as Navistar blocks. GEP is owned by AMG but neither havea foundry to cast blocks so it was contacted out to Navistar for the finished engine and head castings. GEP then assembles the engine.

The bottom line in this is that your engine is a GEP optimizer 6500.

04 26 H is Apr 26 2001

GEP started their numbering with H which stands for 2001.