Awesome

I used an air hammer with a chisel tip and that gets almost all of it out with little effort. You will need to use a wirewheel on the remnants. Use a respirator, the dust gets really nasty.

Well I had a nasty setback today. Feel like I wasted my entire afternoon. I was modifying one of the radiator mount brackets and building the support brackets I needed for the YJ radiator to mount in the MJ when I discovered that somehow I measured something wrong and the YJ radiator won't fit. It's too tall by quite a bit and a little bit too wide. It hits the passenger side frame rail if you try to drop it low enough for it to work. I must have measured thinking it would fit in front of the swaybar, but it won't. Guess I'm ordering one of the more expensive MJ radiators. Also had my daughter pull the battery box out and found more metal that needs patching.

You scored with this one. My buddy keeps teasing me that we should swap the '86 to a turbo diesel.

Driver's side floor prepped for pan: Driver's side pan partially tacked in: Passenger side almost ready for a new pan: Did all that yesterday. I didn't get a lot done today. It's really hot now, so I only got the rear driver's side pan cut to size and fitted in place. The front pans don't need much fitting or hammering in order to fit right, but the rear pan will need a LOT of hammering due to the difference in the floor shape. I figured out how to mount the YJ radiator without a ton of modifications. I'll take pictures of that while I do it. We also figured out a way to modernize the engine vibration damper. I'll follow up with that later. I may get the floors done this weekend if I have the energy. I started back to work this week so I'm trying to finish the big jobs now while I still have the mental fortitude, lol.

My buddy came over last night and we got a TON of work done on the '86 Comanche. I flushed the entire cooling system with the freeze plugs out, put new ones in (old ones were actually fine as it turned out, but still worth it to be sure), then flushed it some more with the new plugs in. I pulled the radiator out. I put the intake and exhaust manifolds back on and hooked everything up. I used plenty of copper gasket spray on both sides of the new gasket, and I used red locktite on the bolts after using a thread chaser on the bolt holes. I torqued them all to 23ftlbs in the correct torque pattern. Is there a vacuum hose diagram floating around on this site? I need to find one. I've got a couple hoses coming off the black vacuum pipe manifold thing behind the throttle body that broke and I'm not positive where one of them goes. The bigger one goes to the back of the airbox, but the smaller vacuum line goes to a 2-port rubber thing that isn't plugged into anything. While I was doing all that, my buddy was finishing cutting out the driver's side floor. He's coming back tomorrow evening and we plan on getting the new pans welded in. The rust goes pretty far up the pedal box under the parking brake pedal, so we're going to have to cut in a patch panel under there. I took the radiator to two different radiator shops today and they both told me it wasn't worth it to try to fix it. So either I order the $230 Crown radiator or I retrofit the YJ radiator I have laying around into the MJ. I test-fitted it yesterday and it will require heavy modification of both radiator brackets on the MJ. Doable, but I don't know if it will be worth it. The YJ radiator is quite a bit bigger. I don't have pictures yet because we were very busy yesterday and my hands were too grimy. Then I was too beat when we were done. Will get pictures tomorrow.

Nope I looked it up and Eagle is right. There IS a gasket for the 2.5 that has only the intake manifold and no exhaust on it. I already bought a regular gasket though.

Say what now? There's no exhaust gasket?

Another small update... finished pulling the exhaust manifold off. Got a lot of carbon buildup in the exhaust ports. Valves aren't coked up too badly. The manifold gasket was definitely leaking pretty badly. I made the EGR blockoff plates. I forgot to take a picture of the one I made for the intake manifold. I'd mess with them more if I was making them for other people, but they were good enough for me. This was that heater hose "T" connection on the '88 that I mentioned the other day. I regasketed the throttle body today and cleaned up the manifolds. Made the block off plates. Tomorrow I'm going to go ahead and replace the freeze plugs while they are really easy to get to, clean the manifold surface on the head, replace the motor mounts, replace the belts and most of the hoses, then start buttoning stuff back up. I'm also planning on finishing getting the driver's side floor rust completely cut out. Haven't been getting much help from the daughter. I'm going to try to get her in the shop with me tomorrow.

Oh, lol. I hadn't looked into that tube. Thanks. If it's not actually pulling exhaust gas then I suppose there's no harm in leaving it in place.

Yes that. So it is indeed more emissions stuff that isn't needed. Thanks.

Alright, I got the intake manifold pulled off and removed from the truck. I have the exhaust manifold unbolted and ready to be removed, but I can't get it off. The engine/intake bracket keeps it from pulling off the single center stud. I don't have another fine-thread nut to use to pull the stud off, so I'll have to wait until I can go to the hardware store to get a nut and take the stud out. Is there any reason to not replace the stud with a bolt? I'm going to make a couple of block-off plates for the EGR system on my plasma table. The one I'm wondering about is the big hose that goes to the bottom of the air intake box. What the heck is that thing? Another EGR system? I might leave it intact in the air box but get rid of the hoses and weld a plate over the hole in the exhaust manifold. Oh yeah, another one of the exhaust bolts was super duper loose. When I reinstall everything I'll make sure I clean the holes out really good, torque everything properly and use a dab of red locktite on the bolts.

Started up the '88 again this afternoon. Started up nice and easy. Went ahead and checked the transmission dipstick and sure enough, there's little to no fluid in it. Explains a few things. Gotta go get some, along with a filter. Removed the throttle body from the '86 over the course of the day. Removed that UFO-looking thing for good measure. Pretty sure it's an EGR? Probably going to delete it. Tomorrow I'll finish removing the intake and getting the exhaust loose enough to replace that gasket, then put everything back together with new gaskets. Then do the valve cover gasket.

Yesterday I replaced the heater hoses, the rotted heater-hose t-section, the upper radiator hose, plus took off the thermostat housing to find no thermostat at all. Cleaned up all the crap that was on there (no gasket), cleaned up the housing, and put it all back together with the proper gasket and thermostat. I replaced the passenger side motor mount while I was at it. Nobody told me how frustrating that would be, lol. Turns out if you jack the engine up a bit above the fender, you can get to the oil filter adapter bolt a lot easier. Had a frustrating day today. Could not get fuel pump to come on with key on. Truck would turn over fine, and was sucking a tiny bit of fuel. Just enough to cough a little bit. Dad came over and helped me try and figure out what was wrong. After a couple hours, finally realized I have no ground at the fuel pump. Traced the wire..... well duh, fuel pump grounds through the bed. I don't have a bed on this truck. Anyway, while trying to find a good location for a ground, we realized the body ground wasn't connected to the battery very well. So while attempting to grind the paint off under the ground strap, I got into the wiring harness and cut 9 wires. Got them all spliced back together and the loom cleaned back up. Added a fuel pump ground. Put the air box and vacuum lines all back together. Truck started right up and runs fine. The transmission isn't shifting, and might be stuck in 3rd gear. Not sure. It slips a bit sometimes as well. Definitely needs a fluid change, have no idea what condition the torque converter is in. Brakes work fine. Engine sounds really good. Cooling system does not hold pressure and puked a ton of gross crap back up through the bottle. When I get time to continue working on this truck, I think I'll swap to a '91+ cooling system for simplicity's sake. Would love to swap to a newer computer system and get rid of all this crappy Renix wiring too. Anyway.... the '88 runs again.

Could not find any locally. Will try next time I'm in Waco. Today I finished up the brake lines and hoses on the '88 and got the system bled. It now has brakes for the first time since I've owned it. I also figured out a temporary fuel tank mounting solution until I get a flatbed built with a fuel cell. Tomorrow - longer fuel hoses, motor mount, then start the truck again for the first time in at least 2 years. Maybe 3.

Now that I know what they are called (Thanks, SX4), I realize they are important. Scout, I will try to find one locally. Probably not worth it to mail them to me.

On the '88, I got the NiCop line looped, flared and hooked up. Driver's side waiting for a new hose. On the '86, I bought a bolt and a couple washers (they didn't have the cupped washer) and installed it. I put the "correct" bolt down on the bottom where the missing bolt was, since that one is much harder to replace. I also found my missing suspected vacuum leak. The throttle body gasket is leaking and spitting out fuel in many places.

New day, more work done on the trucks. Daughter got almost the entire front floor removed. She would have finished but she wanted to ride her horse this afternoon which took up about half her truck time. She found a nice mouse nest in the frame rail. I worked on the brake booster upgrade on the '88. The original rubber boot on the '88 was in perfect shape, as was the foam insert. The ones on the WJ's brake booster had crumbled away. Go figure. I had to shorten the booster rod by 3/4". All put together and ready for install. My welds are not perfect, but I was trying to minimize heat input. I wrapped the shaft and boot with a wet rag, then covered that with foil. It worked, no meltage. For the inspectors among you; yes, I realize I installed the brake switch backwards. I had to fix that in the truck. All installed. share images

I'd assume it's rather rare, since people on this forum (and the Jeepforum) haven't really heard of it happening. But I did find some guys that had that problem. One site claimed it was fairly common.

We-ell....... I may have blown the headgasket by overheating the truck because the thermostat was stuck closed. Not sure on that one yet. I'll have to run a compression test again. I did some research and the manifold coolant passages can and do fail. I don't think the later 150ci engines run coolant through the manifold. Either way, this is just to check.

Daughter and I got a lot of work done today. I had an issue yesterday when I tried to start the truck to move it. I cranked it for a long time and it would cough, but not fire off. Finally, just before the battery died it started when I had the throttle floored. Then it was running like garbage again. Smoking, smelled terrible, not great throttle response. Today, it started and seemed to be running great again, but has throttle lag and if you goose the throttle it stumbles. After running it for a while I realized the radiator hose wasn't getting hot. So, thermostat is stuck closed. Easy fix. New one installed with bleed hole added. Daughter got most of the rest of the driver's side floor cut out while I was working on engine stuff. I'm missing an intake manifold bolt, which I believe is causing more vacuum leakage. The other lower intake manifold bolt was quite loose. I tightened it up. Gotta go find a new bolt now. I worked on the '88 today as well. I got the steering hooked back up. Ready to finally finish the brake upgrade. I had a showerthought last night about the intake manifold on the '86. I wondered if maybe the coolant was leaking into the manifold and getting into the combustion chamber, causing the smoke and smell. I bypassed the intake manifold. I didn't think it really seemed to make a difference in the way it ran, but I thought the exhaust smelled different afterward. My daughter said she thought it was slightly less stinky. I dunno. I have a feeling I'm going to need to get a new intake manifold gasket and install it. It doesn't get very cold here so I don't see any harm in keeping the manifold bypassed.

I received the new/rebuilt injector Monday (not sure if they sent me back mine or an entirely different one), and the truck starts and runs again. Collins Bros did indeed ignore me. Now to finally finish the floors in this thing.

It would make more sense if the injectors were rated at lb/hr instead of psi.... which I think may be the case. I think the source where I got my information may have been off. Either way, the part numbers don't cross-reference. I sent the injector off to GB Remanufacturing today. I haven't heard from Collins Bros. They may ignore my request since I mentioned it's for a Comanche and they only like dealing with Wrangler platforms.

From what I understand, the AMC TBI Injector is set up in between the ratings for a 4.8 V8 Chevy and a 5.7 V8 Chevy. Or 5.0, not sure. GM used a 23psi rating on the smaller V8, AMC used a 24psi rating and GM used a 25psi rating on the bigger V8. That's what I've found so far. So either you'd have the AMC150 running lean or have it running rich... I don't know if the Renix system can compensate much for air/fuel ratio. I know next to nothing about it. It seems pretty rudimentary. I also don't think AMC ever used it on the 258 or the 242. I know there was a fuel injected 258, but they were super rare so I dunno how much information is out there on those. Don't even know if they were TBI or if they were an early MPFI direct-injection system like the later 242 FI systems were.

Small update: Daughter has been very busy and I picked up a new project recently and have also been busy. The truck stopped turning over a couple months ago and sat without anyone doing anything to it. A few days ago I got back to work on it. We replaced the starter and it turns over great, but won't start. I've traced the problem to the injector. The injector is getting a pulse through a circuit light, but the injector itself won't squirt fuel. I backflushed the injector, put it in my ultrasonic cleaner in B12 for a long time, along with other things. I can't get it to fire. I have been having problems tracking down a reasonably-priced injector. The local injector shops say they can test it but can't do anything else. I'm sending it off to GB Remanufacturing in the morning on the off-chance that they can get it going. The only other injector I can find is a Standard Motor Products injector that they want nearly $150 for. I reached out to Collins Bros Jeep and am waiting to hear from them as well. Before you ask, yes, the truck has spark. It runs on ether or the gas that gets into the intake after pulling the injector out.

Video of engine running properly now: