6.2 or 6.5 in HMMWV

[trooper632]

How do you tell if a HHMV has the 6.2 or 6.5 in it. I have an 87 and a 94 M998, the 87 was listed with the 6.2 and the 94 was listed with the 6.5. The 94 model has a blue rebuild sticker on the valve cover done in 2009, but I need to know what engines are in them for sure, thanks

 

[gringeltaube]

If you can't get to see the raised casting number on the flywheel housing then post some pics of the valve covers, at least. Some of us may know which engine is which.



G.

 

[Retiredwarhorses]

94 has the 6.5, the 87 could have either, but the 6.2 has "6.2D' embossed on the right front of the block below the cyl head. Another way to tell is if you have a crank position sensor hole on the left side of the timing cover, where the harmonic balancer is. And there are a few other ways...but the number one way is to look for the GEP label on the left valve cover, GEP never made 6.2's.

 

[Powershift]

Quickest way to tell... the 6.5 has a bypass hose coming off the Upper Radiator hose, 6.2 doesn't. A guy at Gov Planet pointed that out to us.

 

[OPFORMI]

Here is another way, pull the dog house in the cab so you can see the rear of the engine.

 

[OPFORMI]

Here is another way, pull the dog house in the cab so you can see the rear of the engine.View attachment 570547View attachment 570548 Be careful using the bypass hose since they are interchangeable and can be installed on a 6.2. The majority of the 6.2 v 6.5 can be decided that way, but you never now what Joe will use to fix his ride. The guys at GovPlanet told me that was the original advice given to them, but recently they received new info and this should be the go to method to make sure.

 

[Retiredwarhorses]

That's a tach drive...that is standard on both motors. Look, the 6.2 And 6.5 are almost if not identical. The 1990 and above 6.2 was a better motor IMHO, the redesigned heads, injectors and pump made it smoother running.
like I said, the 6.2 is embossed on the engine block, front right. Here is another easy way, check your injector pump, 4523 or 4524 is 6.2.

 

[OPFORMI]

Exactly on the 6.5 the mount bolt is on the right, 6.2 the mount is on the left. Of course this is a last ditch method, if you are lucky enough to have or find the embossing then go with that. Just throwing out alternative methods for distinguishing the models.

 

[Retiredwarhorses]

Agreed, good call....

 

[86humv]

Here's an easy way also....
6.2 water cross over is different and the 6.5 also says GEP on it and has a bigger water pump down hose.