6.2L Diesel advice needed

[710 Burner]

I am searching in earnest now for a 6.2 to put in the Cherokee. Can any of you 6.2 Diesel guys give me any advice what to look for or avoid?

[Belteshazzar]

why? is there something cool about them I'm not aware of?

My family had a suburban with that motor. Slow, unreliable, and not particularly efficient.

[Chevelleguy]

Because they are inexpensive, can be built to about 200hp (which is plenty for a DD) get about 20-22mpg, fit on SBC motor mounts, and fit well in the engine bay.

[ninjaneer]

Check out Diesel Place for potential engine health-related issues.

Also check out

http://www.dieselplace.com/forum/showthread.php?t=220268 (http://www.dieselplace.com/forum/showthread.php?t=220268)

to see what you'll run into when installing it. There are a few helpful install threads if you search this site as well.

[budojeepr]

A few things I found out:
- If you can drive it, run through this:
Start it cold, make sure glow plugs work. Observe smoke. If white smoke persists, it may have a blown head gasket. Happens a lot on these if they're abused.
Warm it up, see if smoke clears, idle smooths out.
Drive, get the usual impressions you look for.
Once it's good and warmed up (operating temperature), turn it off, wait a few minutes, and try starting again. If it doesn't start (just turns over), the injection pump may be worn. That's an expensive repair (ask me how I know).

- See if you can get a 6.5 instead. There were a lot of improvements made to the block casting for the 6.5, and later is better, from what I hear.

Good luck, and welcome to the soot-shooter world!

[RubiconMike]

why? is there something cool about them I'm not aware of?

My family had a suburban with that motor. Slow, unreliable, and not particularly efficient.

I have an '89 Chevy G20 full size van with the 6.2. It may be slow, but it's faster than my '82 Cherokee with the 6cyl!. It will also pull a trailer on the freeway at 70mph all day long. (Takes quite a while to get to 70, but once there, it cruises) I regularly get 18mpg overall, and have seen as high as 22mpg on the highway. Not bad for a huge box with no aerodynamics!

I've had it since 1990, in that time I've had the glow plug controller fail, which fried the glow plugs. The transmission failed once due to a poorly made part from the factory, other than that, every problem I've had was the van stuff, never the motor. I change the oil, air, and fuel filters on a regular basis, and that's pretty much it for maintentence.

Imagine having a FSJ that never breaks............... :)

[thomastenn]

look for a later model with serpintine belt drive they have the internal upgrades that fixed the plagues of the early models. beware of military engines as they have a 24volt system and i think youll need to replace the injection pump and other related items to the 12v civilian models

[Lindel]

IIRC, the mil versions have a mechanical pump, but I could be wrong about that, been a while.

[Belteshazzar]

I have an '89 Chevy G20 full size van with the 6.2. It may be slow, but it's faster than my '82 Cherokee with the 6cyl!. It will also pull a trailer on the freeway at 70mph all day long. (Takes quite a while to get to 70, but once there, it cruises) I regularly get 18mpg overall, and have seen as high as 22mpg on the highway. Not bad for a huge box with no aerodynamics!

I've had it since 1990, in that time I've had the glow plug controller fail, which fried the glow plugs. The transmission failed once due to a poorly made part from the factory, other than that, every problem I've had was the van stuff, never the motor. I change the oil, air, and fuel filters on a regular basis, and that's pretty much it for maintentence.

Imagine having a FSJ that never breaks............... :)

that's fine. I just hadn't had a good experience and didn't see the sense of it.

[710 Burner]

Yeah, my Cummins is no race rocket either, but it will tow my boat all day and give back 20 MPG while doing it. with the air on. up hill.
I have a line on an older model (84) van that the owner says has been rebuilt, heads reworked, inj pump rebuilt (?) new lift pump, I can hear it run but the tranny is "bad". I have asked what "bad" means exactly and am waiting on a response. I have also found a newer model 6.5 but I don't really want to have to deal with an ECU.

[The PIG Smith]

I have an '89 Chevy G20 full size van with the 6.2. It may be slow, but it's faster than my '82 Cherokee with the 6cyl!. It will also pull a trailer on the freeway at 70mph all day long. (Takes quite a while to get to 70, but once there, it cruises) I regularly get 18mpg overall, and have seen as high as 22mpg on the highway. Not bad for a huge box with no aerodynamics!

I've had it since 1990, in that time I've had the glow plug controller fail, which fried the glow plugs. The transmission failed once due to a poorly made part from the factory, other than that, every problem I've had was the van stuff, never the motor. I change the oil, air, and fuel filters on a regular basis, and that's pretty much it for maintentence.

Imagine having a FSJ that never breaks............... :)
HERE HERE!!
I've got a '93 GMC 3500 extended length cargo van which is just as you have described about yours.
It's no Speed Racer, but it will get out of its own way rather smartly.
I've not checked the milege as I know I need to replace some injectors, but it does much better than the 360 in my J20.
I would like to get 18-20mpg, but its 14FF rearend is stuffed with 4:10 gears, so I am not getting my hopes up.
The only think I dislike about my van is that it rides like a tractor.
My cargo van is a steel box on wheels...very loud (no interior), rough riding (9700 GVW)

A 6.2 is a great Diesel swap canidate for a FSJ.
I bought my van as a donor for a FSJ, but I've decided to hang onto the van for a while.

[The PIG Smith]

I have also found a newer model 6.5 but I don't really want to have to deal with an ECU.
The way to get around the ECU is replace the DB4 electronic Injector Pump with a DB2 mechanical pump from a 6.2.
Afterwards...NO stinking computer as the engine is now a total mechanical motor!

[FSJ-Jackson]

look for a later model with serpintine belt drive they have the internal upgrades that fixed the plagues of the early models. beware of military engines as they have a 24volt system and i think youll need to replace the injection pump and other related items to the 12v civilian models

The only 24 volt parts on the military trucks is the glow plug controller and the starter, otherwise it is all 12 volt.

[poolmike]

Watch for cracked heads! They are also notarious for cracked blocks. Beware of any 6.2/6.5 that has been rebuilt, a lot of machine shops don't get the boring tools lined up properly and the rear cylinders get bored all crooked. I learned a lot of $expensive$ lessons building mine, and by the time it was complete, I didn't want it anymore. I sold it for a fraction of my investment and dropped a 4bt in the truck. Go industrial the first time and don't worry every time you drive it! Just my opinion.

[Karl Streich]

If you stick with NA then make sure you have open intake and exhaust, it does wonders for performance on a diesel.