Top C

Bought in Spotsylvania Co Va. over two years ago. Updated the computer to 1990. Replaced the fuel injectors to the 4 point injectors. New water pump and updated the cooling system by removing the Heat vacuum valve and adding a coolant reservoir. Put a 3" lift on it. Moved the Vacuum reservoir from the from bumper to the fire wall. Replace the instrument cluster to full gauge cluster. The vehicle aside from the paint is in very good condition. Plan on having it painted next spring. Has 4.0 engine Automatic Transmission with 4 wheel drive.

Ok so I'm sure I'm in the right section but I wanted to register my MJ with this site. I don't much about the history of it except I bought it from a Co-worker The Vin number is 1JTMP631XHT189821 1987 JEEP COMANCHE AUTOMATIC TRANSMISSION FOUR WHEEL DRIVE 4.0 ENGINE This is all the information I can provide at the moment. Please if I'm wrong area could you let me know I will do what to move it. Thanks Mike

Okay I'll get the info when I get home tonight and send it to you. Thank you!

Okay thanks for the info on the Mod. Still wondering about looking inside the HVAC box without pulling the dash apart to see if the insulation might have fallen down and is blocking the heat somehow. Mike

Okay who should I provide the vinnumber to and is there any other information that they need for me? Thanks Mike

Pete M So I'm curious, if we provide a VIN number to you, you run it through Chrysler and get a build sheet and birthday? Thanks Mike

Eaglescout526 What mod did you do to get all the heat?

HI SCGuy Yea I was just posting that someone else mention the form on the door. What does that insulation attach to? If I pull the fan motor out could I see it that way? Water temps are good going in and like I said earlier slightly less come out which I would expect. Mike

Yea sounds like you have same problem. I've checked everything except taking the dash apart and I don't want to think about doing that. I was reading different posts about the same problem but all them mostly refer to that Vacuum heater valve on the water line. As said I remove that a while back just because everyone said that will fail eventually. Some did mention in a post about insulation possible blocking the air flow through the heater core. I was wondering if I removed the fan motor if you could see inside the box enough to see if there was something blocking the air flow. I do get good air flow when I move through the different vents along with the defroster. So I don't think that's a problem. I wanted to see if anyone else has something to say here maybe we'll both learn something! The water pump has been replaced and thermostat is new also I forgot to mention that in the earlier post. Mike

My MJ seems to have low heat. I removed the heater hose valve and have flushed the heater. I've measure the heat at inlet and outlet and its slightly cooler at the outlet which I would expect. Does anyone here have any experience with this? I'm wondering if there is a blockage in the heater box not the heater its self which is not letting good air flow though the heater coils. Does anyone have a real picture of the inside of box housing the air condition unit and heater? The Air conditioner does work and does cool as I would expect. Also I was wondering if there is some kinda of inspection door or someway to see inside the box without taking it apart. I've looked but I didn't see one. Thanks Mike

Update on the Windshield Wash Nozzles. I found a 96 Cherokee that had the same cowl and nozzles. Removing the nozzles was piece cake. I got and an assortment of screws and hose that went with the nozzles for $5.00. I got home pulled cowl off and cleaned everything up and installed nozzles. Start the MJ up to check the work and there was no difference in the spray. I dragged the air compressor out and blew through the line from the water tank up to the nozzles and that seemed fine. I did one more test I disconnected the water line at the T and put my finger over the open hose to see if I had pressure and that's when I found a hole in the line just beneath the wiper motor. You couldn't see it as the hose is very short. Replace the hose and all is well now!

No I didn't I will though. I needed to pull the wiper arms off and I was going to drive the truck to the yard tomorrow so I just took a couple screws out to look under the cowl. I'll investigate more tomorrow hopefully I can find some nozzles and then I'll have them ready to go if it isn't the t connection. I would think I would see water somewhere if this was happening. Thanks Mike

I looked on my MJ and nozzles are not adjustable that I can tell. I got a brand pump thinking that was the problems I got good flow coming out. I think I'll make a run the junk yard tomorrow morning and see what I can find. My nozzles are built into the cowl but I pull the screws out of Cowl and look under the Cowl where nozzle are and they look like they can be replace fairly easily. I wonder if there is any size difference between 87 and a 2001? I would imagine they were in the Cherokee line only. Mike

I rather new to this where should I move this and how do I do that? Thanks for your help Mike

I need to replace the front windshield washer nozzles. I replaced the pump thinking that it wasn't providing enough pressure to get the water up higher on the windshield but that didn't solve my problem. The nozzles are clean and the hoses are good so the only thing left is to replace the Nozzles. Has anyone had this problem and if so where did you find nozzles? Thanks Mike

yes I found that out I use to own a couple old XJ's and thats what I look for if I can't find parts for the Comanche but thank you!

Is there a pump number for the pump you got I was looking on rock auto too but didn't go far enough I guess

My 87 MJ windshield washer pumps but the pressure seems to be low. When it comes out the sprayer nozzles it hits low on windshield. I have second bottle and washer and tried it and got the same results. I've clean the line up to the nozzles with air and they are free. I've got good ground and voltage at the plug for the pump. Is there one replacement pumper better than another to get better pressure to get the water higher on the windshield? Thanks for your advise in advance. Mike

Thanks to everyone I've located one

Looking for a OEM windshield washer bottle for 87 Jeep Comanche Thanks Mike MZFB@aol.com

Its beautiful day here got up early to do diagnostic work on the MJ. Since it was HVAC vacuum problem I dropped the Vacuum canister and check it for leaks and cracks along with vacuum lines leading from the canister back to HVAC and the vacuum motor. I found the main vacuum line was good no cracks or leaks in the canister either. I found the the line at canister going back to HVAC was leaking so I didn't have vacuum at the HVAC or the vacuum motor. Since I was going to have to run a whole new line from HVAC to the canister, I just moved the canister back to the Firewall which of course now keeps all the lines shorter. Very easy move and less likely hood of another line failure. Thanks to everyone that help me with this. Mike

Thanks everyone I haven't check it yet as it's been raining pretty heavy here but I will check the lines from the firewall. Jason I don't have cruise control so I guess I'll move the canister closer to the firewall. This way I can keep an eye on the lines that run to and from it. Hopefully tomorrow I can get out there and look at it. Mike

Jason I have the oblong one. Does it matter? Mike

Jason Thanks yes it was all hook up. If does rain tomorrow after work I'm going to take a look at it to make nothing got disconnected. Mike

I recently became aware when I accelerate in my 87 Jeep Comanche the bi-level vents switch to the defroster vent and then back after the engine speed levels out. I believe I may have a vacuum line problem somewhere but I have not found it yet. Has anyone experience this before? Also while I've got your attention does anyone know why the Vacuum reservoir bulb is mount all the way up front? I was thinking about moving it back up near the fire wall. I've done away with heater vacuum switch and all the stuff related to that switch so I have room to move it somewhere in that area. There must be a reason for that reservoir to be where it is. Thanks for your help in advance Mike