Hey All,

I recently made the jump to a .GOV auction truck

93 GMC K1500 4x4 with 6.2 Diesel.

What should I be looking for on pick up and before I try to crank up this beast?

I will need to replace the battery, but what else should a novice Diesel Dude know to check out?

BIGGER_HAMMER

My first thought was "a different truck".

Sure it's a 6.2 and not the 6.5? I'm not sure when it changed but somewhere in there.  The 6.5 is what's in the humvees.  


It's not a modern common rail which is good and bad...so basic diesel things apply. If it's sat for a while it's probably full of water in the fuel....pick a fuel treatment and dose the shit out of it. Change the fuel filter.  Glow plugs might need to be changed.

If glow plugs are bad you can cover the exhaust to help the hot gasses stay and start the motor

The military HumVees had a 6.7 version of the 6.2. Mechanical injectors and pump.

Clean the tank out, change the fuel filter, make sure the lift pump (on the frame rail under the driver's seat) works. Don't use starting fluid!!!! Check your battery cables REAL GOOD!

Most likely your '93 has the mechanical injection pump. They aren't too bad. Early electronic pumps really suck, most have been replaced a few times.

 

Ok, Humvees were offered with both 6.2 and then later the 6.5. they actually have more in common with the van engines than the truck engines but that is simply cylinder head design.

In 1993 you could order a Chevy truck with either a 6.2 NA,and the 6.5 Turbo.

If it has a turbo it is a 6.5, If it a 1993 it has the DB2 Mechanical pump. and a GM3 or 4 turbo.

As for a auction truck, The glow plug relays and plugs themselves are common to go bad, easy to change and cheap but beware that the plugs have the tendency to swell inside the head and can be a major bitch to remove without breaking in half.

You will need two hot batteries, the 6.2/6.5 platform really likes it cranking speed.

If a 6.2 it has a cartridge fuel filter at the back of the engine, looks like a silver box and is held down with a spring steel wire like a master cylinder lid.

At the front of the engine just to the drivers side of the injection pump is a little brass petcock, this is a fuel spigot. Crank the engine for a couple seconds, then have someone else crank it while you crack this petcock open if diesel flows out you have diesel to the pump. If it still isnt running look at the fuel shutoff solenoid.

These engines are easy to work on and get quite a bad rap because frankly nobody understands their quirks.

I had a 6.5 I built in highschool that put 362HP and 556 FTLBS on the rollers. I fabbed manifolds for a better flowing turbo and lived and breathed the fuel injection system trying to squeeze power out of a engine that was designed for economy.

Thats not alot of power but it was enough to spank most of the 12v guys

I drive a Duramax now and make twice that power with half the money and labor

Thanks.

I understand the truck has the N/A 6.2 GM diesel.

It is a Civilian (Non-CUCV) truck running 12 volt system.   Will it need two batteries?

BIGGER_HAMMER

It is set up for two.

Dont get me wrong, I have started them on warm days with only one battery but they start WAAAAAAAAY easier with two. Especially yours being a 6.2 without the gear reduction starter.

If it still cranks at the speed of smell check the battery cables, they corrode and get hard as a rock.

I have a quickie question.



I got the Truck home and noticed I have

(A) a cable that is not hooked up after change of the batteries...

(B) a warning light that was not on when I picked up the truck

So, figuring (A) & (B) might have something in common.

(A) This is on the Driver side of the truck.  I changed out both batteries.

I noticed that due to the windshield washer bottle, the drive side positive terminal has a different post.

I have this left over, so I figured it has a red marking so I most likely would go to the positive terminal, but figured I should ask the 6.2 Diesel Gurus for their expert opinion.





It has what looks like the Mother Of All Fuses on it.

(B) What would make the low coolant light come on, (the radiator and overflow bottle are properly full.  The coolant is a healhty fresh green and gets warm to the touch but doesn't boil (ran with radiator cap off turning heater off and on to see if maybe an air bubble was in system.

Any and all help is appreciated!

BIGGER_HAMMER

That hooks to the positive side of the battery, but that ring terminal isnt a factory piece. someone has changed it and done a half ass crimp

As for the low coolant light, there should be a sensor in the top of the radiator and sometimes the connections on the wiring harness get dirty or pulled apart enough that it opens the circuit and the light comes on.

If there is no sensor on the radiator it will be in the coolant overflow bottle, the later 6.5 trucks had them there.

Looks like a solid truck, did you get it fired up with no problems?

Once I replaced the dead batteries, it fired right up.  

Jump in, twist the key and it fires like any gas car or truck.  

No wait, no hesitation or black smoke, just the beautiful clatter of Diesel early in the morning...

It was expecting a Forestry Service or Federal Bureau of Prisons or even Border Patrol Truck

Turns out Mongo II (a strong but simple brute) is a former Navy C.U.C.V.





If I ever sell it, I am SURE it will draw "top dollar" because it could have been a Navy S.E.A.L.  Delivery Vehicle...  

BIGGER_HAMMER

Good to hear, sometimes they are finicky. How many miles did they rack up on it?

And its not a SEAL delivery vehicle, its a US Navy Slow Attack Vehicle

It only has 37K.  Everything seems to be working good except the cabin fan blower.  

All lights, turn signals and wipers work.  

I figured it was a "diversionary device", as all that diesel clatter moving so slowly would simulate a tank battalion on the move to attack...

I'd like to find some CUCV wheels.  I've heard that some CUCVs have been running HUMVEE tires which helps with highway speed with those 4.56 rear ends.

37K is great, and out west I bet it is rust free (Bastards)

The Humvee wheels and tires will bolt on but beware, they are 37's.

Are you sure you have 4.56's? If you open the glovebox there will be a 4x2 white sticker on the "floor" of the glovebox. It will have all the option codes for your truck.

GU6-3.42
GT4-3.73
GT5-4.10
HC4-4.56

Or, if it is missing shoot me your VIN and I'll decode it.

If you have 3.42s you really dont want the heavy Humvee wheels.

Hummer wheels on the old.84 to 86 cucv require spacers because the backspace. Might want to check that for this style of truck if you go that route.

That is also a k2500 incase you are looking for parts. Buy brake components and suspension listed for 8600 gvwr vehicle.

You mean the 12v guys who weren't even trying?

Look guy, Just cause you took out your fuel plate and removed the silencer ring on the turbo, that doesnt make you fast.

There was a alot at play and how I set that truck up, and remember I was in highschool, most of the guys I was racing were on stock charger/trans.

Didnt win them all but won enough, had more time in tinkering with that engine than most people could fathom but the dyno numbers dont lie

Now I have a Duramax and diesel hotrodding isnt my go-to thing anymore, I found 800hp in cars way more exciting than 800hp in trucks

hummer wheels have 7" of backspacing.  At least my truck (Avatar) the hummer wheels were modded to 3.5" backspacing.



Unless you plan to air down to like 10 psi off roading (or just want to look cool) just stick with plain 16.5" rims and hummer tires.

Thanks!  Now I just need to find some reasonable priced HUMMER tires...  

BIGGER_HAMMER

Those things are on Government Liquidation all the time.

Like I said, the guys who weren't even trying.

I getcha, I getcha.

Damn truck was a hell of a sleeper though