Yesterday while I was repairing the door hinge on a friend’s Jeep Cherokee, I noticed it had been running rich. I checked the ECU codes and found code 13 and 52. 13 is an unresponsive MAP and 52 is O2 rich.
I first swapped in a spare MAP, cleared the codes and started it up. I got he same rough idle and soon the same code in the Check Engine light.
With the engine still running, I pulled off the vacuum line and noticed there was no vacuum. The line looked fine. I pulled off the other end and found vacuum at the manifold. The line was obviously clogged.
As I was walking to pull a spare off the parts rig, I noticed a tiny spot on the bottom of the line that was melted. I never found the source of the melting, but the Jeep ran much better after replacing the plastic hose. The MAP and Rich codes cleared up as well.
There are two different brake calipers used on the Jeep Cherokee. The earlier Jeeps, 1990 and before, use two cylinders with 7mm hex key slots. The later, 1991 and newer, use two 13 MM blots to hold the caliper in place.
In either case, begin by lifting and securely supporting the Jeep.
Remove the wheel.
To improve access you can rotate the steering so that the brake caliper is facing out. However unless you have longer than stock brake lines, don’t turn it all the way or you will have trouble getting the caliper off the brake pads due to the brake line.
Remove the mounting bolts or cylinders using a 7MM hex bit or 13MM socket as needed for your year.
On the earlier models, the ones with he 7mm cylinders, the brake pads stay in place and the caliper slides off them. On the newer ones, the pads come off with the calipers.
In either case use a pry bar to rotate the top of the caliper back to slide it off. On the newer one, if there is a groove in the rotor you may have to push the pads back into the caliber slightly to get it to slide off. In severe cases, you may have to loosen the bleeder screw to get it to compress.
When replacing the earlier style it is a good idea to replace the Teflon sleeves that go around the cylinders when you replace that caliper. At least inspect them before reinstalling the caliper.
Sometimes the caliper can be stored by placing it over the lower control arm. In most cases it is best to use a wire to tie it up while the other brake parts are being serviced. Do not let it hang by the brake hose.
If new brake pads are being fitted, you will need to compress the piston back into the caliper before they are refitted. I use a large C clamp to push the piston in. Or you can use a caliper compressor tool.
To replace the caliper, slide it into place and carefully feel for the fit of the retaining bolts or cylinders. They should start easily by hand. If not remove the caliper to see why it is not aligned. These bolts can be easily cross threaded and a thread repair is not easy on the knuckle. So avoid cross threading by carefully aligning the caliper when reinstalling securing bolts or cylinders.
Reinstall the wheel and properly torque the lug nuts.
Before moving the vehicle, be sure to pump the brake pedal a few times to take up any slack that was generated by pressing the piston back in.
Begin by obtaining the proper sized O rings. These are available from your local Jeep dealer or from a Crown Distributor like me. It is important that you get the proper sized O rings as you don’t want fuel leaking down on the hot manifold.
You only need a few simple hand tools to replace an injector or change the O rings. On the 90 and earlier Cherokees, the fuel rail is held in place by four bolts with 13 MM heads. You will need a pick to remove the old O rings. I found a magnet handy for getting the bolts out once they were loosened.
Also, since you are going to be spilling fuel on a potentially hot manifold, be sure to have a big fire extinguisher on hand just in case.
Even if you are just replacing one injector, you have to remove the entire fuel rail. On this 1989 Cherokee, the rail is held in place by four bolts.
After the bolts are loose, I used a magnet to fish them out of the brackets.
With all the bolts loose, pull the fuel rail away from the manifold. This will pull the injectors out of the manifold. To service an injector, first remove the electrical connector. I use a pick to gently pry the clip back so it will pass the detente on the injector. Be careful not to loose the clip as they are expensive to replace.
Next remove the clip that holds the injector to the fuel rail. It just slides off. I use the pick again to help get it moving. Don’t loose these either as they are not available form Jeep separate from the fuel rail.
One it is unclipped, pull the injector out of the fuel rail. Sometimes it helps to twist it, to get it out.
I used the pick to pull the old O rings off the injector. Note: on the Jeep, the brown O ring goes on the manifold end and the black O ring goes on the Fuel rail end.
Insert the injector back into the fuel rail. I found it helpful to put a drop of oil on the O rings to get them back into the fuel rail. Again twisting it helps to get it in. Reinstall the clip that holds the injector to the rail. Make sure the slots are properly aligned. If they are not, you may not have the injector seated properly. The clip will slide on easily when the injector is properly seated.
Twist the injector to the proper position and reconnect the wire. Make sure the clip seats with a click in the detente.
Repeat with procedure with the remaining injectors.
One you are ready to reinstall the fuel rail, carefully align the lower part of the injectors with the manifold openings. Use the heel of both hands to press the fuel rail into place and seat the lower part of all the injectors.
One the injectors are seated, replace the bolts that hold the fuel rail in place. Look around for vacuum tubes that have been knocked out of place during the procedure. The MAP sensor line and the vacuum line to the fuel pressure regulator will likely be knocked loose by moving the fuel rail around. reconnect them before starting the engine.
Turn the key to on and listen for the fuel pump to run. Do not start the engine yet. Inspect for leaks first. If you see a leak, loosen the fuel rail and wiggle it around to seat the leaking injector. Again twisting the injector may help.
Once you have a seal, start the engine and check for leaks again. If you see any, shut off the engine immediately and reseat the leaking injector.
Day two in Harlan dawned wet and foggy. We slowly crawled out of our tents. I found Scott Paulman working with a leaking bead on his XJ. He used his Highlift jack to break the bead and clean the debris that had collected there. We tossed it in the back of my Jeep for a run down to the air supply at the bottom of the hill. There we reseated the bead and filled it with air.
Frosty treated me to some of his farm fresh eggs cooked on a propane grill. We said good bye to Adam as he headed out to attend to other obligations for the weekend. Then we started planning the day. One of my favorite trails from our last trip to Harlan was Rail Bed and I was ready to run it again. So we decided to go there first and work our way back through the park.
Wayne Klotz junior and senior arrived and unloaded and next Jennifer and Janice arrived. We lined up the Jeeps and headed up the Putney Trail. The overnight rains had made the trail a bit slick in places and this provided a great warm up for things to come.
About half way up the mountain we met a pair of off roaders coming back down. There day had ended early with a broken rear drive shaft on their Wrangler. Getting past each other took a while on the narrow trail especially with one of the Jeeps being injured.
At Middle Fork we all took a run up one of the play hills and headed on out to The South side of the park. We really appreciated all the new signs that Harlan County parks has added. Good use of the grant money in my opinion.
We found Rail Bed and somehow, I ended up in the lead as we poked around for the way in that does not require going up the water fall. I switched on my front locker and headed up the rocky trail.
My favorite thing about Rail Bed is that it is all rock. No mud mixed in. And the rocks are big enough to be challenging but not so big that they overwhelm my 33” Maxxis Buckshots.
At the end of the trail, I noticed that the ground around the last big rock had really eroded away compared to the last time I was here. I elected to take the easy way out and skip the last boulder. Well, the easy way out is not so easy any more either. There is a name sake piece of rail road track that has been uncovered by the erosion right at the apex of the climb threatening to slice the tires of any one who stays in the ruts. I gave it one try but I slid into the ruts right at the rail and I decided to drop back down.
The second option for and easy out is to squeeze by a tree on a very narrow ledge. This is made even more challenging by a strategically placed rock that the bottom that prevents lining up the way you would prefer and by a root at the base of the tree that requires a bump right where you don’t want to bump. Also, should you miss, there is about an eight to ten foot drop on to the rock you are trying to bypass below.
I picked my way up carefully and made it past the scary part just fine. I parked and went back to watch the others coming up behind me. I missed most of the action but I got back just as Wayne was taking the bypass exit. I spotted him around the rock and he chose the narrow ledge as well.
Next up was Jenny enjoying the traction of her new rear Lock Right locker. I spotted her around the rock and she took off up the hill. She may have bounced on the tree root or the ground may have given way, but for what ever reason, she suddenly found her left front tire dangling over the edge. See the video here: http://www.youtube.com/watch?v=_grDOT3o3LA
She held firm on the brake pedal while I ran up to get my winch cable. Wayne Sr. took my cable and hooked on to her front tow hook as I held by brake and spooled in the cable. The tire slid back to the bank but was firmly hung on the root s and would not pull back over the lip. The Klotzs grabbed her tow strap and quickly secured her B pillar to the tree for extra stability.
We tried to have be back up to pull the front tire back onto the surface but that caused her rear tire to slip over the edge making for an even more serious situation. Neal Hoover realized we needed another winch ASAP so he made the run up the cut with the piece of rail track partially blocking it. He made and incredible drive up the hill and turned just at the right moment to miss the tire slasher and pop up over the crest. He got his winch cable connected to the back of her Jeep and she was again stable.
Janice held the brake in Neal’s Jeep while I held the brake in mine. I could not see well from the seat of my Jeep so I handed my winch controller to Neal. He held his wireless remote in one hand and worked my winch with the other. Matt remarked that he looked like he was playing X box winches as he maneuvered Jenny’s Jeep.
After some tense moments she was finally back on stable ground. She drove up the rest of the way parked and ran to find a place to pee.
Next in line was Matt. As he approached the tree on the ledge he started to slip on the tree root as well. When his spotted motioned for a turn to the left, he just shook his head no. His spotter called for a bump and again he shook his head no. Eventually he carefully powered his Jeep over the root and up to safety.
Next, the guys with larger tires decided the safe way out was to go over and around the last boulder. They all made it out just fine.
After we all calmed down some we headed to the nearby lower rock garden to play around.
It was there we saw a very strange contraption. It had the body of a XJ, the grill of a CJ and the frame and engine of something Fordish. It seemed to be abandoned there.
Next, we headed up to a new trail called Killin’ Time. Neal got caught between a rock and a hard place and several of us decided to abandon the run and go watch from the nearby road. When Josh made his run he got hung at about he same place as Neal did. Neal climbed in the back of Josh’s Jeep and gave a demonstration of how active ballast works as a traction aid. Neal jumped out and Josh made it up the rest of the trail.
Next we found our way to Profanity. This somewhat difficult climb was made even nastier by the wet slippery mud. I was near the back of the pack and watched as several Jeeps made the climb. As the trail was getting more and more torn up I decided to take the parallel climb along with Jenny. About that time, Wayne popped the bead on his rear tire and had to back down. I went back down and assisted with getting his tire changed.
As we were getting ready to move on, Jenny noticed her power steering was not acting right. We popped the hood and saw fluid every where but in the reservoir. There was no apparent leak in the hoses so we collected fluid form the group and tried it again. Evan looked in to see if he could see the leak as Jenny turned the wheel. Fluid sprayed out everywhere as he jumped back. The source of the leak was found and it was the pump shaft seal.
We told her not to steer more than necessary and headed back up the trails. Back at Middle Fork, Jenny asked Evan to drive her Jeep back down trail 45 as he power assist was coming in and out and she did not want to battle the tricky trail 45 without it.
Back at camp, Evan loaned Janice and Jenny his BMW for a parts run while he and I started removing the damaged power steering pump.
Fast ride to town
New members Ron and Tracy had arrived at camp by this time so the rest of the group took them out to see some trails before dark. They found a beautiful vista on a trail we had never explored before.
Even and I had the pump off before the girls got back with the replacement. When they arrived we were ready to pop it back on when we saw the new pump did not have a pulley, just instructions on how to reuse the original one. Instructions like, “Do not use a hammer!” We tried several methods to remove the old pulley but eventually decided to we had to have the correct puller. Evan and I headed back to town to take advantage of Advance Auto’s loan a tool program.
Back at camp and armed with the proper implements, Evan removed the old pulley and pressed it on the new pump.
We got it all bolted back up just about dark and left the filling and bleeding for morning. We settled in by the campfire for and evening of food and fellowship.
New Transmission mount
The BA 10 transmission uses a different mount than the other transmissions. For a long time these mounts were hard to get after Chrysler discontinued them and there were no after market part available. However, now Crown Automotive makes a replacement. Part number 8350 5567.
Years ago when mine broke, I repaired it by placing a bolt in the center to hold the two halve together. This was meant to
be a temporary repair but has been in place for several years now. The bolt had begin to loosen and more wear had allowed the mount to move around under load. Old worn jeep transmission mount
So tonight I replaced it with the Crown part.
I began by supporting the transfer case on my transmission jack. I then removed the four 13 mm nuts that hold the cross member to the mount. Next I removed the four 15 mm bolts that hold the cross member to the Jeep. Next I removed the four 5/8″ bolts that hold the mount to the transmission. This is different from other Jeep transmission that only have two bolts holding the mount. The mount also holds the exhaust but that just slips out.
To install the new mount I first warmed up the rubber that holds the exhaust as it was very cold in the shop. This heating allowed the hanger to slip easily into the mount. Next I installed the four bolts that hold the mount to the transmission.
Next, I lowered the transmission slightly on the jack and attached the cross member to the mount using the four nuts. As often happens when the mount is worn or broken, the cross member was offset form its mounting holes while on the jack. I used a pry bar to move it into place and started the first bolt.
I jacked the transmission back up into place and I then started the other three before tightening them all down. I then lowered the jack and checked the torque on all the bolts.
