Jeep 4.0 headgaskets?

[RoadWarrior222]

Hey gang,

On a scale of one to f*** that, how much do I want to do a head gasket on a Jeep 4.0?

Been seeing some nice Grand Cherokees going real cheap lately with blown HG.

I guess I'm asking, how common is it to blow water to oil and screw up bearings, and how common is it the head warps, do you need to take more apart than you might in a T-M, that sort of thing.

thanks,

RW222

[Rrider]

In for info cause I want one too.

[thedon809]

Never done one but I can't imagine they are too difficult being a pushrod engine. I bet the head weighs a lot though.

[RoadWarrior222]

Yah heard somewhere they were heavy fuggers.

[thedon809]

I just moved my head with intake and exhaust+turbo attached and that was pretty damn heavy.

[shackwrrr]

Super easy, no timing to mess with. Unbolt rockers, pull push rods, unplug electrical, unbolt exhaust and use 140000ton crane to remove assembly.

[shackwrrr]

Oh and unfortunately grand cherokees have pretty low resale value. They are built nicely and its definitely a good deal as a daily driver.

[RoadWarrior222]

But where else you gonna get an '05 luxo barge for $1500?

[GLHS60]

I think 2004 was the final year for the inline 6, lots of 3.7 V6 and 4.7 V8 G.C.s with engine problems available.

Thanks
Randy

[shackwrrr]

Makes more sense to see 3.7/4.7 grands for cheap. The engines had some issues, usually headgasket/valvetrain issues. If doing a gasket I would reccomend a new head, they are very picky about head straightness and lack of machine ability.

[RoadWarrior222]

Guess maybe the '05 I saw was a 3.7 then, just said 6 cyl, doesn't run, maybe needs headgasket.

Why are they unmachinable? Ford claims none of theirs are... but I've done it... okay I dissemble slightly, I got one machined, and the other I hand lapped.*


(* Though I wish I had known about this first... http://wiki.seloc.org/a/Cylinder_Head_Fire_Ring_Peening because it was a porous biatch and I had to keep going for hours because pits kept appearing in the gasket sealing areas. Doubt hand lapping is something you wanna consider doing with a straight 6 head though, too long.)

[thedon809]

Tight tolerances I guess. Might mess with timing depending on how much you shave off. A 3.7/4.7 head is super easy to pull though...if you have the chain holder special tool that is.

[135sohc]

No 'head saver' head gaskets?

[thedon809]

Maybe. I don't mess with aftermarket stuff.

[onerippinturbo2]

the 4.0 was/is known to crack cylinder heads so if you do in fact buy one, keep that in mind and at least get the head magnafluxed before you reinstall it.

[RoadWarrior222]

Hmmm, I'd probably ghetto-flux it.... oldskool method of checking castings pre-magnaflux.... whitewash it, then ping with hammer, see if lines appear from oil pumped out of cracks due to vibration.