My 1986 2.5 woes, with pictures of my truck.

[Dogote]

I really like my 1986 X 4x4, 5 speed, 2.5 Comanche. I had wanted one for quite a while when this one came along, and it's a rust free little truck.

I have limped it along for the last year. I never have needed to drive it more than 5 or 10 miles a day, maybe once or twice a week. Perfect for a 30 year old truck, I'll never wear it out. I dealt with it not running great and leaking oil because I didn't have the time or space to work on it last year. Now that I am in my new shop (airplane hangar) I have some space. Time is still tough, but I am trying to spend as much time getting project done as possible right now.

 

Now onto what this post is about. In trying to fix all my leaks, both vacuum and oil, I discovered my compression on the rear cylinder is 60 PSI cranking and 30/70 leak down. The exhaust valve is burnt a bit and it needs a valve job.

 

The truck has 196K on it. Supposedly the engine was overhauled at some point not too long ago, but I doubt that. The cylinder walls are smooth, like really smooth, except for a single vertical score, barely distinguishable by finger nail micrometer. I investigate further tomorrow. 

I'm looking for input on my choices here. 

 

1. First choice, yank the engine, but a 4.6 Cherokee off Craigslist and swap the engine and anything else I need into it. 

 

Positive= A bad @$$ comanche

 

Negative= I bought this to use as cheap little classic truck. It won't be cheap to start swapping engines and I am not sure I want to spend the time.

 

2. Pull the engine, have it tanked and machined, install an over haul kit.

 

Positive= A nice, reliable, stock 2.5 Comanche.

 

Negative= Time

 

3. clean up the valves, throw the head back on and install some new gaskets and hoses.

 

Positive= The cheapest and fastest route

 

Negatives= It may need rings or mains at any time, won't be "trouble free" like a freshly overhauled engine.

 

I am leaning towards option #3 just to get it done.

[Dogote]

[Dogote]

 

 

 

[benjy_26]

That thing is CLEAN. If you just plan on cruising it, I'd keep the 2.5. I use mine for back country exploring (I do a lot of survey work) and the stock 2.5 has held up well to my use. I'd check the clearances on the main and rod bearings if possible and check the cylinder walls for wear. If all looks good, get the head rebuilt.

[MJanky]

What about finding another 2.5 to swap in? Depending on where you are it could be easier and less expensive to source a good one than to put work into the one you have.

 

As a bonus if you don't need to exchange it for the core you'd have a spare you can rebuild at your leisure.

[Dogote]

Okay, here's my plan. I am going to get the head done. I was thinking of doing the valve seats myself, but I have a Nu-way and a Serdi carbide valve seat cutter set up. They are more geared to 5 angle valve jobs on racing motorcycles. I have done 100's of Ducati heads, 100's of BMW heads, and probably 50 KTM heads, but I think I would rather pay to have this head done since one ruined cutter from my set up (or having to buy a different size cutter) is as much as a complete head job from the machine shop.

 

My oil pressure is good until the gauge gives up after 20 minutes of running (I have a new sender to install) and the cylinder walls are fine, plus it doesn't burn oil and the rest of the cylinders have minimal leak down past the rings. It will last through the summer and if I need to, I can overhaul at a later time. I may keep an eye out for a 2.5 on Craigslist, overhaul it, and then swap out the short block when it's done. At least by the time I am ready to swap in an overhauled short block, I will have a lot of other things done already and won't be messing with a ton of time consuming details.

 

The master plan for my Comanche is:

 

2.5" (on a JK unlimited) RK brand coil springs up front

Bilstien 5160 remote reservoir shocks from my JK

Add a leaf and shackles in the back to raise it to match the front.

31x10.5x15 mud terrains.

Better steering components, such as a heavy duty tie rod, but at the very least, all new rod ends and ball joints.

 

I don't want it any more than what I would consider "lightly modified" I mainly want it to look cool, work a little better on forest roads, be able to haul a little more, and still be able to be returned to stock if I, or the next owner wants it that way.

 

As I have time I'll make a pre-style bumper and a better rear bumper (currently has some weak tube bumper with a bent hitch receiver) I also want a rack over the bed. I've been drawing some and almost have a plan. I want it to look more expedition than construction. I'd like to be able to leave my Canoe or Kayak on top most of the summer. I live at Lake Chelan (Huge recreation lake) and work next to the Columbia river, . Last summer I left the Canoe on the truck using a Yakima roof bar on the cab and put the other end on the tail gate. It was nice to be able to hop in the truck and already have all my canoe gear in it. I'd like to have it level and be able to haul stuff with out pulling the canoe off. 

The paint looks good from 20 feet away, but the clear coat is pealing. I have seen a few internet examples of doing a very light wet sand, and then re-clearcoating paint with pleeing clear coat and sun fade. The results were not like a new paint job, but were pretty damn good and kept an original "patina" look. I may give that a try.

 

Even in it's current state, people comment on it being a cool little truck. It's been a while since having an older truck or car to play with. I'm having fun so far, despite the mess I make with it on my nice white floor.

[benjy_26]

Sounds like you have a good plan! Can't wait to see what you end up with.

[mikekaz1]

That truck is great looking!

[87Chief]

Nice shop.  :bowdown:

[mark 39]

      Great shop! What's  models are the Trumpets ?

[fiatslug87]

      Great shop! What's  models are the Trumpets ?

...Triumphs, damn spellchecker!!!

[Dogote]

Nice shop.  :bowdown:

Thank you. Believe it or not, it's a mess right now, and I am not all the way unpacked from moving. I need to insulate and drywall, as well as build a clean room with an office above.

[Dogote]

      Great shop! What's  models are the Trumpets ?

 

The two Triumphs are my buddy's. 1968 T100 Tiger and a 1970 something 250 Cub. The Ducati's and Guzzi's are mine. In the pictures you can see a Guzzi 500 Monza, a Guzzi 750 Ambassador frame, a Ducati 450 Desmo RT, a very custom Ducati Sport Classic 1000, and a Ducati Monster 800. Not in the pictures are a KTM 1190 Adventure R, a Ducati Multistrada 620, and 6 other pre-1970's Ducati's. My wife and I have had a bad bike habit for the 25 years we've been together. Of the bike mentioned, most of them are hers.

 

These pictures only show half the shop/hangar. The metal wall in the center is coming down when my renters lease expires. The whole building is 105 feet long. There will be 3 or 4 airplanes/helicopters parked in here and my toys will be put away along the edges, or at home. I bought this with the intention of owning my own helicopter business, but then work got really interesting and I am holding off and taking things slow with getting going on my own for a few years. 

[mark 39]

        My wife likes Aermacchis (Aermacchae?). Must be hard to give up that much shop space. But business is business.  Your MJ 2.5 motor is a good engine, not exciting, but reliable and economical. I bought a used '88 2.5, 2wd with 4ax  in '96 that I used as a DD for 12 years, sold it  to a friend who drove it for another 4 years until road cancer killed it. Compared to my current '87 4.0 it seemed "lighter" and more nimble. Which ever way you decide to go, you have a nice starting point.

[Dogote]

        My wife likes Aermacchis (Aermacchae?). Must be hard to give up that much shop space. But business is business.  Your MJ 2.5 motor is a good engine, not exciting, but reliable and economical. I bought a used '88 2.5, 2wd with 4ax  in '96 that I used as a DD for 12 years, sold it  to a friend who drove it for another 4 years until road cancer killed it. Compared to my current '87 4.0 it seemed "lighter" and more nimble. Which ever way you decide to go, you have a nice starting point.

 

Aeromacchi, from Aeronautica Macchi. They built the Harley Sprint 350's and other great bikes. The factory in Varese Italy is in an old hangar on Lake Varese. It is pretty much where the first float planes were built, and where the plane that eventually morphed into the British Spitfire was produced. I was in that factory in 2007 and at the time they were building MV Agusta motorcycles there.