Category: Car repair

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Replacing Bumps stops on the Jeep Cherokee

Replacing Bumps stops on the Jeep Cherokee

The bumps stops can take a lot of abuse on the Jeep Cherokee. Evan a street driven Jeep may need to have the bump stops replaced after a few years. It is important to keep good bump stops in place because the suspension can over travel without them. In the front, the axle can damage the transmission cooling lines and in the rear, the leaf springs can become damaged.

The rear bumps stops are very easy to change. Usually there will just be a steel plate bolted to the unibody frame rail where the rubber has broken away. This plate is held in place by two bolts with 13mm heads. If they are rusted in place, it may help to spray penetrating oil inside the frame rail. If the bolts break off, you can simply weld the new bump stops in place.

New bump stops are available in a variety of lengths to compensate for larger tires. The stock length bump stops are available for around $10 each.

In the front, the bump stops are located inside the coil spring. This means the spring must be removed to access the bump stops. On the AMC built XJs the bump stop screwed into the tube inside the coil. On the Chrysler built Jeeps, the holder is welded to the tube and the new bump stop slips into the cup. To install the new one, I found that lubricating it with hand soap makes it slide in easier. If the spring is removed, you can use the weight of the Jeep to press the bump stop into place.

Longer front bump stops are available, but I have had better results using the stock sized bump stop and placing a spacer at the bottom of the spring seat. Spacers can be made of wood or plastic. I have even seen tennis balls placed inside the spring to lengthen the bump stops.

Bumps stops should be inspected before and after each off road trip to ensure that they are in present and in good condition. Having the proper bump stops in place will help your suspension work properly and keep your tires from rubbing the fenders.

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Exhaust Manifold Replacement Jeep Cherokee

Exhaust Manifold Replacement Jeep Cherokee

After removing the old manifold and finding it too broken to repair, I ordered another one form my parts supplier Crown Automotive. I get great service from Crown and they supply quality parts. Their parts are near duplicates of the original Jeep parts and I can order with the Jeep part number.

I received my boxes early in the morning. However, one of the boxes was crushed. The box with the gasket was damaged as were the main manifold gasket and the air filter I had ordered. The doughnut gasket was fine as were some of the other parts in the box. I returned the damaged parts.

I compared the manifold to the original just to make sure it looked the same. It seemed well made but with some kinda sloppy welds. Just like the original.

I began by installing the EGR pipe in the new manifold. I had to heat the old manifold to get the EGR pipe out and the fitting at the end still did not want to swivel. I screwed it in the manifold and lined it up with where it would need to point to attach to the intake.

I cleaned off the head using a Scotch Brite wheel mounted in my drill. Luckily I had a spare gasket so I installed that. I then mounted the new manifold. It is way easier to get to the mounting bolts with the intake out of the way.

I then cleaned up the manifold mounting surface and sat it in place. Since it is very hard to get the bottom manifold bolts started, I tried setting them in place and loose hoping I could slip the manifold in behind the thick washers. I forgot about the dowels that the manifold has to slip over. So, I had to pull the manifold back out and pull the bolts.

Once the manifold was seated into place, I began the tedious task of getting all the bolts lined up and started into their threaded holes. The ones on the bottom were very hard for me. Once I finally got them all in I remembered to finish hooking up the EGR line. I had slipped the tube into the hole as I set the manifold in place but not started the nut.

I tried every possible angle and I could not get the nut to start. It would go in a thread or so and then pop back out. I tried from above and below. The tube looked aligned but it was obviously just a hair off. And with it seized in the exhaust I could not move it much to try to align it.

After struggling for an hour or so, I gave up and pulled both manifold back out. I found I could easily thread the pipe in with the manifold laying on the floor. I hoped that if the exhaust end freed up that I could attach it in place in the truck. So, I heated the nut cherry read and sprayed AFT on it until I could spin it around on the tube. I bolted the exhaust back in place and tried again. I tried it with the nut started in the intake but then it would not thread in the exhaust. I tried it with the nut started I the exhaust and it would not start in the intake. I wiggled the intake around every way I could but I could never get the nut to start.

So I took both manifolds off again. While I had the exhaust out this time I decided to remove the air warming tube because I don’t use it and it is really in the way for getting to the bottom bolts. I laid the manifolds on the floor and hooked up both tubes. I tightened the nuts almost snug but where the tube would still move a bit.

I then set the entire assembly in place as a unit just like I had taken it out. Putting the back nut on the exhaust mounting stud was a real struggle that involved some yelling and throwing wrenches before I finally worked my hand into the correct position. Eventually I was able to get all the bolts started into their threaded holes. I snugged up the EGR tube nuts and hooked up the down pipe to the new manifold.

I was tired and sore by that time so I called it a night and I will finish tightening the bolts later. Then I will have to hook back up all the vacuum and electrical connectors.
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Broken Exhaust Manifold Jeep 4.0

Broken Exhaust Manifold Jeep 4.0

I have been hearing an exhaust leak in my off road Jeep Cherokee for a couple of years. Knowing that the 4.0 manifold is likely to crack, I did not think much about it. However, the noise has been getting worse and I am starting to see some indication that the leak was causing some cooling problems under the hood.

So, I decided to take a look to see how bad the crack was. I began by using a mirror and a flashlight. I pulled the air box to get more room. I was able to look over the front four runners pretty well and found no visible cracks. I know that the later HO manifolds tend to crack where the two section join. But this is the older style manifold that has one main tube and the runners are welded to it. No matter how I twisted the mirror, I could not see the back two runners.

So I decided to pull the intake and take a look. In some ways the old Renix manifold is easier to remove and in some ways it is not. One of the things that makes it easier is that the whole injector wiring harness can simply be unbolted at the firewall and stay with the manifold. There is no need to disconnect the individual injectors.

I did have to disconnect the three sensors below the engine. The O2 sensor, the block temperature sensor and the knock sensor all had to be disconnected to let the wiring harness stay with the manifold.

I had to remove the power steering pump from the bracket to access the bolt that holds the bracket to the manifold. Then I removed the fuel and vacuum lines. I was not able to get the EGR line to break loose so I had to remove the intake and exhaust manifolds as a unit.

Once I had them out and on the shop floor, I was able to get the EGR line to break free from the intake. I immediately saw severe cracking on the last runner near the O2 sensor bung.

I flipped the manifold over and saw cracking around the number five runner as well. I pulled on the pipe sand the last two runners separated completely from the manifold.

I had planned to re-weld the cracks but after seeing how broken up the pipes were and how brittle the surrounding metal was, I decided to order a replacement. I looked into getting a header but there are few to choose from for the older engine. I also thought about retrofitting the HO manifold but that would have meant redoing the down pipe back to the catalytic converter. I decided to simply replace it with a stock type manifold from Crown.

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Trying to move an old bus with air brakes

Trying to move an old bus with air brakes

My friend Ed has an old School bus that he uses mostly as a mobile storage shed. However it has not been very mobile for the last couple of years due to a problem with its Holley carburetor.

Last fall we pulled the carburetor and over the winter he rebuilt it. I put it back in place yester day. We expected the bus to start right up and he was going to use it to move and store some furniture. Well as many adventures in repairing old autos go, things did not go quite according to plan.

The carburetor was easy to install and hook back up. The fuel line was no where to be found so we made a run to the hardware store for some copper line and a fitting. Ed showed me how to use his flaring tool to make the proper flare to fit the inlet of the Holley.

We rigged a temporary fuel supply with a rubber hose and a gas can. He hit the starter switch and nothing happened. The battery voltage just went down. I moved my Jeep in position and hooked up the jumper cables. Still, the starter would not turn the engine.

So we added the battery form his tractor to the mix. There was very little voltage sag when all three batteries were in parallel but still no rotation of the starter.

We tried turning the engine over with a socket on the crank but the nut just turned without turning the engine. We then decided to try to rock the bus with it in gear.

The trouble was, the bus has air brakes. You can’t move it without having air pressure. The compressor is driven by the engine, so with out the engine running there is no air to release the brakes.

We finally figured out how to rig and air line and a small compressor to air up the air tanks. This procedure however involved lying under the bus while holding the air chuck on the filler valve.

We finally got the brakes to release, but the bus was pretty stuck in the dirt. It took quite a bit of tugging with my Jeep and pushing with his tractor to get it to move. However, we did finally get it to move. I pulled it up the hill with the Jeep.

The idea was to let it roll down the hill and pop the clutch to get the engine to turn over. Well all the time spent towing and working the brakes had used up all the air. So we had to run cords and hose up the hill and refill the air tanks for the run down.

We finally go the bus to roll free, but we were still not able to get the engine to rotate. We knew by then that we would need to pull the spark plugs and lubricate the cylinders to get it to go. We were once again out of air and energy. We used the tractor to get the bus out of the driveway and called it quits for the day.
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Jeep Cherokees Off Road at Golden Mountain

Jeep Cherokee Off Road at Golden Mountain


This weekend, Jenny and I met up with some of her Facebook friends at Golden Mountain Off Road Park in Sparta Tn. We took along our two Jeep Cherokees both with three inch lifts and 33 inch tires.

I normally trailer my Jeep, but in an effort to save fuel, I decided to drive the 100 miles to the park. Jenny’s is her daily driver so she drives it every where she goes anyway. The lack of carpet, sound deadening and a muffler made it impossible to hear my cell phone.

I was pretty tired by the time we made it to the park. However, I got my energy back as we pulled off our doors and aired down the tires and disconnected Jenny’s sway bar. Mine is long gone and makes for a wiggly ride on the road.

We son met up with Andy, Jimmy and Ben. They all had much larger tires and lifts than us so they let up lead the way.

We headed up trial one on the left side of the park. Often this trail which is marked as easy is very slick, but it was dry enough for us to handle this day. We made the turn onto trail 10 and enjoyed the step descent and then the climb back up to the top of Bounty Hill. The descent was much easier this trip because the little tree that was in the way of the proper line down the rocks is now gone.

We met the other guys back at the top of the hill and sat for a while and talked while the kids played.

Next we decided to run the inner loop on trail 12. We started off making the climb on trial 11. This is fun rocky climb. It seemed a bit tougher this trip than before however as the heavy rains had washed out some of the smaller rocks. We all made it up with only a few back ups.

We hit 12 and made our way around. The others stopped to play on the rock climbs of trail 38. We were not able to finish the loop however due to a tree across the trail. We turned around and met back up with the others. We then parked for lunch and watched a group of buggies climb the hill. We got to watch a flop right off. They flipped him back on his wheels quickly and he continued the climb.

Next we made our way over to trail 14 and made the loop. We got a bit confused on the multiple trails there and ended up coming back out the way we went in instead of making the circle indicated on the map. This was probably the most technical trail we ran al day. It took about 30 minutes to get both our rigs through about 100 yards of rocks. Jenny’s tie rod got a bit tweaked in the process, and she put some scrapes on her new skid plate. I got to test my new diff cover as well.

After that we ran trail two and Jenny had a run up part of trail 16. We parked for a while at the pavilion and enjoyed the scenic views before heading back down.

We went in by the picnic shelter and down trail 11. It is always fun to go in that was as it does not look like a trail until you actually drop off the ridge behind the shelter. We took trail two back to the parking area and put our doors back on. We said good bye to our new friends and headed south.

We found an air compressor just a few miles down the road and aired up our tires. I was pretty tired by the time I got home. But it was a good tired. Off roading is a great stress reliever.