Tips on picking out a 6.2, 6.5

[Gunfreak25]

Next month i'll be meeting with a fellow here in town to pick out a 6.2 or 6.5 for my M211 project. I am not that knowledgeable about either motor, though I am very mechanically inclined. Just wondering if there are certain things to look out for. He said some have the banks turbo and some don't. Obviously, i'll want yhe turbo.

Are there certain years to avoid and why? I've done a few hours of reading this evening and it appears for a 6.5 I will want to find a pre 1994 motor as they have the mechanical pump instead of the electronically controlled pump.

They both sound like good motors but as I understand it some 6.5's were plagued with small problems.

Just want to make an informed choice..

 

[Barrman]

The pre-'94 IP is what you want for the 6.5. The 6.5 everybody wants is the 2000 and newer GEP made version. It has all the stuff right that GM got wrong.

However, the little stuff matters if money is a concern. 1988 and older means V belt and normal water pump. Newer and it is a serpentine belt with reverse rotation water pump. Be carefull you don't get to mixing and cost yourself several hundred dollars for a new pump by accident.

There are several threads about the GEP 6500 engine used in HMMWV's. They tell it better than me.

 

[Gunfreak25]

Thanks for the heads up! I do not want a V belt setup, and it seems from the reading I just did they were standard on all after 1988. So that means I will need a 1988 or older motor. If I can't find a pre 88 6.5 I will just pick out a good 6.2. I don't need a turbo that badly, the 6.2's even sound less troublesome than a lot of the 6.5 stories i've been reading. And yes, money is always a concern. Thanks again!

 

[Chief_919]

Thanks for the heads up! I do not want a V belt setup, and it seems from the reading I just did they were standard on all after 1988. So that means I will need a 1988 or older motor. If I can't find a pre 88 6.5 I will just pick out a good 6.2. I don't need a turbo that badly, the 6.2's even sound less troublesome than a lot of the 6.5 stories i've been reading. And yes, money is always a concern. Thanks again!

There were no 6.5's in 88.

However, some 2000+ GEP 6.5.s did come with V belt setups from the factory, they were used in place of 6.2's in a truck that needed a 6.2. They were non turbo engines.

I have one here now, with a civilian 6.5 turbo on it.

 

[Gunfreak25]

Quick question, do the front of the heads have the 3 bolt holes like the rear of the heads do?

http://img1.classistatic.com/cps/po/110115/368r1/69376e8_26.jpeg

 

[bearboley]

Find a 599 6.2 block and add the 6.5 turbo with the mechanical IP best set up there is. Just look out for injector length the older 6.2 they have long injectors and they wont clear the turbo, but the last three military 599 motors I had already had the 6.5 heads on them I assume they did this so they only had to stock one style head, but you know what assume means.

 

[bearboley]

And yes the heads do have three bolt holes on the front and the motor in the pic has the short injectors

 

[Gunfreak25]

Thanks for the info! The three bolt holes on the heads look like they match the pattern of the bolt holes that came with the 455 Olds that was in the truck. That means the mount I made for the 2 cylinder air compressor should fit without too much work and I won't have to make an entirely new mount. Same for the big 24V generator which I want to keep.

 

[Alredneck]

If youre in Memphis anytime stop by and you can pick through about 20 different 6.2 humvee motors. $350ea

 

[Gunfreak25]

That would be awesome! I wonder how much shipping would be from TN to Yuma?

 

[Alredneck]

I am headed to Cali at the begining of Sept.

I like playing in the desert so a detour may can be arranged!

 

[Gunfreak25]

That would work out real nice! You going to bring your M35? We have the sand dunes here that are just over a half hour away from Yuma. They are in California, of course.

PM sent

 

[Gunfreak25]

I finally scored! In the next couple days I'll have two AM General made 6.2's on their way to Yuma. He's going to pick out two real cherry motors. They are fresh HMMWV take outs and as usual they are missing the alternators and starters. But he thinks he has 1 of each he can include so I have a ready to drop in motor. Going to pick up an adapter plate to mount it to the Olds pattern Th400 I have which came with the truck. The previous owner made the custom driveshaft so I don't have to mess with that. The only thing I have to do is lift the thing in and fab up 2 new motor mounts. Not sure what i'll do with the other motor, I guess spares are good to have though.

Any way to date GEP motors via a block casting? I'll get pictures when they arrive!

 

[Recovry4x4]

FWIW AM General didn't make any 6.2 engines. If they are 6.2, they are GM.

 

[Gunfreak25]

Perhaps he is mistaken then? He said he has late 80's and early 90's GEP 6.2's. I'll confirm with him tomorrow. Sure can't find any info on the net about them. All I see are the GEP 6.5 optimizers.

 

[Recovry4x4]

Info on GEP!
Product Information | General Engine Products | AM General LLC - Mobility solutions for the 21st Century

 

[Gunfreak25]

Yup, nutin on the 6.2. I'll be happy with whatever I end up with though.

 

[spicergear]

Good choice on NOT wanting the V-belt versions. Pretty amusing actually, the they factory designed a belt stretcher on that engine as you have the same size crank pulley with a couple grooves in it, then two different size pulleys on the water pump...being driven from the crank pulley! Hello? GM? ...anyone home?? I like how the upper radiator hose has a hose clamp with a shield built onto it as the belt would keep loosening and stand a chance of rubbing the upper radiator hose. Nice set up.