Kicking around the idea for a 1g Monty...

[corprin]

I have been struggling to figure out if I want to build my ExPo rig out of my '05 Liberty CRD, or '99 Cherokee.... till I stumbled across a 91 Monty LS with a bad motor locally. The dealer is listing it as a 106k old truck with no dents and "some rust". I live in MN, but from CA, so "some rust" scares the hell out of me. The motor was pulled apart by some fool, and abandoned.

Here are the listing pics...

They are asking $400 for the rig, and I am VERY tempted.

I have been doing a ton of reading on the tucks, and they seem to fit the bill quite well. Sadly, much of the detailed information I am seeking is not found anywhere, so I figured I would start here before jumping headlong into 4x4wire (i'm skerd!). I have the ability, experience and knowledge to complete the implied tasks associated with my ideas.

1. The engine is a 6g72, but what is the transmission? I know later models have an A340/variant, bolted to the 6g73, but what about the early automatics? Do these follow the same A340 case dimensions, or is the A340, or one of its variants, swapable?

1.5. *Solved* What is the engine/bell housing flange differences between the 6g73 vs. 6g72, the 12v-6g72 vs 24v-6g72, and FWD vs RWD? I ask this because if the Monty I is compatible with a later trans, I open a WORLD of opportunity with JY available engines/trans/t-cases


2. Has anyone swapped in the later 6g73 or 24v 6g72, and if so what kind of fuel economy increase is seen? I know the Monty II nets between 15-20, but what might the same engine/trans type do in a 1000lb lighter vehicle?

3. I noticed there is little mentioned about engine swaps for the chassis, or Monty's in general, is this born in the inherent durability of the 6g platform, or that people tend to avoid such work?

4. Where are the problem spots should look on the chassis for rust/damage/issues that I should avoid, and what is a deal breaker?

thank you all, and I look forward to hearing your thoughts.

Rich

 

[scrubber3]

1. I don't know
2. Not sure
3. I am sure you can put whatever you have the money and time for. I would personally love to see someone stuff a small block chevy motor in one!
4. I know that the second gens are very resistant to rust. I am sure that this carried over from the first gen platform. I am not aware of any trouble spots other than check it over very good. especially the metal brake lines. Which I am sure you already know.

Overall, if it checks out good for everything but the engine then I feel it would be a good project for a price of 400 dollars. Though if you basically explain to the fine dealership that current has it that without a motor they will likely never sell it then they may let you have it for even less. I am sure they didn't pay over 200 for it.

 

[corprin]

1.5 Solution.

From: http://6g72rwd.forumcircle.com/viewtopic.php?t=9

There are to date four families of 6G7X engine blocks.
The first one of interest is the original 6G72 SOHC 12V and the DOHC 24V engine. Although the two engines do not have the same block as far as interchange they are of the same architecture. There are differences in the cast ribs on the sides of the blocks

The second in line is the 6G74 DOHC, this engine was derived from the G72 but with the added 18mm deck height.

The third is the SOHC 24V series of engine in various displacements.

The fourth, in 2001 a redesigned block was introduced with numerous detail changes in the 3.5 G74 and 3.8 G75 displacements.
I will add details later, bear with me this is just the beginning here.

There is a great amount of interchangeability between these families.
The rear face of all the 6G7X engines are the same. They all have the same bolt pattern on both the crankshaft and the bellhousing.
The side mounts. There are some variation in the blocks castings for the bosses on the sides of the blocks but with a little ingenuity the main engine brackets will interchange between all of the blocks. i myself have installed a 2006 3.8L derived from a Galant into a RWD application using the side brackets from an early 3.0 Montero. Not every bolt could be used since the castings were different and one bolt hole on the right side needed to be moved and enlarged from 8mm to 12mm.

The front face,
Oil pumps for the most part will interchange between engines but the radius where the oil sump mates up is not the same. Oil filter locations will be either left front face or on the right side face of the oil pump housing. There are no differences on the block as far as filter location.
Waterpumps will interchange between engines. The front section of the waterpumps are essentially the same with the rear section being interchangeable allowing for different choices in water plumbing.

This is good news as the Gen 2's with the A340 use an identical outer casting as the entire A34x family . This means there is a ton of ability for adaptation from there.
See http://www.4x4wire.com/forums/showflat.php?Cat=&Number=485664&page=&view=&sb=5&o=&fpart=all&vc=1

 

[corprin]

1. Aisin Warner A44DL