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Rear Main Seal Leak Jeep Cherokee

Rear Main Seal Leak Jeep Cherokee

Last night I did another rear mail seal on a Jeep Cherokee. I still remember the first one that I did with lots of help from my Dad. In fact he did most of the work. We could not figure out how to get the pan out from under the engine. Based on some instructions we fond on the internet at the time, he ended up unbolting the oil pump and letting it fall into the pan to get the pan out from under the Jeep.

Since that time I have done several more. Each time I find I can unbolt slightly less to get the pan out.

Once the oil was drained, I first unbolted the starter and pushed it aside. I left the electrical connections in place and just set it to the side. I should have disconnected the battery cable at the battery but I did not.

Next I unbolted all the clips holding the transmission lines in place. There are several of these that all have 8mm headed screws. This allowed the lines to be moved around as needed to maneuver the pan. Also disconnect the oxygen sensor at the connector by the pan. This will prevent possible damage to the wire when putting the pan back in.

I then removed all the bolts from the pan. There are several different sizes and types of fasteners in the pan. And some have extra clips on them. So you need to devise a method to keep track of them so they go back in the right holes. I laid them out on my work table in a pattern I could follow going back in. You will need a deep well 7/16 socket and a 1/2 inch socket to get them all out.

I had trouble with all of the double decker bolts that held clips. They all came out of the pan when I tried to undo the nut that is supposed to hold the clip. I simply left them as assemblies until time to put them back in. Then I took them apart so I could properly install the fasteners.

With all the bolts out, I tapped the pan with my fist and it separated easily. That is the nice thing about working with the later model one piece gasket. If you are doing an earlier one with the four piece gasket; be prepared to drive in a knife blade to make the pan separate. You will then have to straighten the pan once you have it off.

Getting the pan out from between the axle and the oil pump is the tricky part. Yes, it will fit if it is turned just the right way. Holding the pan by the sump and facing forward, slide the front of the pan up the track bar to the left. Pull the rear of the pan to the right so that the flange is against the bell housing. Once it is properly aligned, it will slide right out. Tapping it with a soft hammer will help align it. It is OK to flex the pan a little to get it out if necessary. Removing the shocks will allow the axle to drop to get a bit more clearance. Also, you can disconnect the track bar. However, it is not necessary to do either of those steps as the pan will come out if it is properly twisted.

The rear main seal is in the rear main cap. Use a 13/16 socket to remove the two bolts and drop the cap. The cap fits snugly so you may have to use a pry bar to work it out of the recess in the block.

The lower part of the seal can be easily removed from the cap. The upper part of the seal is a little trickier to get out. The seal is square in cross section and can be seen from below. The trick is to use a soft punch to get the seal to move around the crank shaft to rotate it out. The seal usually sticks but will move freely once it moves the first little bit.

This Jeep was particularly stubborn. I was not able to get the seal to move using my brass punch or even a screwdriver. I eventually made a drift using a piece of ¼ inch key stock. I was able to set the key stock against the seal and use a hammer to strike it firmly to get the seal moving. Once the seal moved a half inch or so, I was able to use a pair of needle nose pliers and rotate it slowly around the crank to slip it out easily.

Putting the new seal in can be tricky as well. First of all make sure it is turned the right way round. The thicker side of the seal faces the front of the engine.

Coat the seal with grease or oil. Slip the seal into the hole and begin to slowly work the seal into the slot. Push the end of the seal with one hand while holding the seal tight against the crank with the other hand. Be careful not to nick the seal. If you encounter resistance, stop and back it out some before proceeding. Once the seal is all the way in, align the ends so that they protrude the same on both sides.

Install the lower seal half in the cap. Put some RTV on the sides of the cap and push it up into the block. Install the bolts and tighten them evenly. Torque them to 80 foot pounds.

Clean the pan and the gasket surfaces thoroughly. Getting the pan back in is also tricky; especially the part about getting the gasket in at the same time. Note that you can use the newer style one piece gasket on the older pan.

To get the pan back in, twist the pan similar to how it was removed. Push the front of the pan to the left over the track bar. Don’t worry if the transmission lines end up on the wrong side of the pan. You can move them later. Pop the pan through the opening and align it with the engine. Now you can set the gasket in place and work it around the oil pickup. Sometimes it is helpful to use wire ties through a few of the holes to keep the gasket aligned as you lift it into place.

Put the bolts back into their respective holes leaving them all loose until they are all in. Note that the two at the back, have a strap that helps tighten the rear of the pan against the seal.

Tighten them all snugly and evenly. On this Jeep, I used a Felpro gasket that had metal inserts in the bolt holes to prevent crushing the gasket. The front four bolts are threaded into an aluminum part; so be careful not to over torque these. The rest are into steel and are pretty forgiving unless cross threaded.

There is one bolt that is difficult to reinstall. It is directly above the exhaust manifold and requires a swivel on the socket to get it out. Use care to make sure this bolt and the others are threaded in straight before tightening them all evenly.

Next, install clips on the studs and reattach the transmission cooling lines. Reconnect the oxygen sensor and place the wire is in the clips. Reattach the starter. Make sure the pan drain bolt is tight and then refill with oil. You may want to put in a fresh filter at the same time.

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Ignition repair on 1995 GMC Suburban

Ignition repair on 1995 GMC Suburban

My 1995 GMC Suburban has had a bit of a stumble for a while now. It runs fine most of the time but will occasionally hiccup and stumble. However lately it has gotten worse and towing the trailer has been a bit of a struggle.

I began by replacing the distributor cap and rotor. The cap is held in place by two Phillips head screws. It seemed a #1 Phillips fit better than the more common #2. I swapped the wires over to the new cap one at a time to make sure I did not mix any up.

Before installing the new cap I installed a new rotor. The center of the old rotor was obviously burned. I just pulled up on the old rotor to remove it from the distributor shaft. The new one pressed on by aligning the tab in the slot and pressing it down on the shaft.

I then set the new cap in place and tightened the two screws. I made sure all the plug wires were properly routed and started the engine to test. Most of the stumble was gone but it was still down on power when towing.

When swapping the wires, I noticed the coil wire looked especially bad. When the truck started running really bad on the way home from Harlan, I stopped at Advance Auto and picked up a new set of wires. I swapped the coil wire in the parking lot and headed back out. The engine immediately ran better. I had had trouble starting from traffic lights but that problem went away pulling out of the Advance Auto parking lot.

I waited until I got home to swap the rest of the wires. I was happy that the set included all the proper length wires. Sometimes these lower cots sets don’t have the right length wires but all these fit nicely with a couple being an inch or two longer which made routing easy in the factory clips.

I laid out the wires on the shop floor in order of length. I then pulled off one wire at a time and picked the corresponding length wire to replace it. I did open up the loom clips and release all four wires form one side of the engine at a time. However, I only had one wire off the distributor cap at a time to avoid switching any wires.

The four original wires on the passenger side had extra protective sleeves on them. I transferred these to the new wires. These sleeve help protect the wires where they go behind the transmission dip stick. I put all the wires back in the separator clips and made sure they were routed away from heat as much as possible.

Several of the wires were burned up where they connected to the spark plugs. I noticed that the engine idled smoother and revved up smoother after I swapped the wires. I will have to wait for a test drive under load to know how much the new wires have helped.

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Video from the XJ list Fall Crawl

Tombstone is a trail we have all run in the past. Now it has washed out into a much more challenging obstacle. I was content to just watch.

Josh decided not to run Lion’s Den this year after having trouble on the entrance.

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Leaf Spring Repair on the Trail

Leaf Spring Repair on the Trail

This past weekend in Harlan, Ky our group experienced two serious leaf spring failures. In my case I was able to get my jeep back to camp make repairs there. In the second case, we had to repair the Jeep before it could be extracted from the obstacle where it broke.

On my Jeep, I noticed that the rear axle was moving back under braking. It would sometimes contact the rear of the fender opening. I carefully drove I back to camp minimizing the scraping on the tire.

Once I removed the wheel, I saw that the center pin of the spring pack had sheared off. This loss allowed the axle to move the rest of the spring pack along then main leaf.

I used a floor jack under the axle to support it. I then used a Hi Lift jack to lift the body of the XJ enough to unload the spring. I sat the Jeep down of a large log to give it stability during the repair.

After removing the U bolts, I was able to line up all the leafs of the spring pack and drive out the remainder of the pin. I then went into town and was able to buy a new set of pins at Advance Auto.

I used a screwdriver to line up the holes in the leaves and slipped the new pin into place. I used two C clamps to compress the spring pack while I tightened the pin. Once the spring pack was back together, I used a ratchet strap to pull the axle back into alignment with the spring pack. I then used the floor jack to press the pin into the hole in the axle.

I then reinstalled the U bolts and tightened then securely. I remounted the wheel and removed the blocks. I will inspect the other side and replace that pin in my shop at home.

The second leaf spring failure of the weekend was more serious. At the end of an especially difficult obstacle, my friend broke the main leak spring just in front of the axle tube. This breakage allowed the axle to move forward and back uncontrolled as well as side to side some. He was unable to move more than a few feet at a time.

His Jeep was also in a precarious place. We were able to get the spring back into place enough for him to roll back down to a somewhat level spot. We then used the weight of the Jeep to force the two parts of the spring close to the correct position.

Next we used two C clamps to press the main leaf into the supporting leaves. Friction between the leaves held it together. He added several wraps of baling wire to give some lateral support. He then added a ratchet strap to keep the whole assemble from sliding apart to the rear.

Which the spring secured in this manner, he was able have his XJ winched out of the hole it was in and then he was able to drive it a few miles down the trail to where we could pick it up on his trailer.

Through some clever thinking and working together, both of us were able to keep our Jeeps going. By working with the tools and supplies available both Jeeps made it home safely and without an expensive tow bill.

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Free Energy Machines

Free Energy Machines

All my life I have been fascinated by the concept of free or perpetual energy machines. I have studied the inventions Nicola Tesla. I have researched many proposed methods of producing energy form a vacuum. So far I have been disappointed by all of them.

Today I clicked on an ad for the HOJO motor. It is supposed to produce energy through eddy currents in an aluminum plate or something like that. It turns out they are selling plans that used to be available for free on the internet but where pulled when they were proven to be fakes.

I guess I still hold out hope for a perpetual energy machine because of a story my Grandfather Strawbridge told me. He told me that during his apprenticeship at a machine shop as a boy he helped his mentor build a motor that ran off virtually nothing. It was small but very powerful. He said even as a strong young boy he could not stop the motor from turning.

My Grandfather’s story takes the usual conspiracy twist that all free energy marketers add. He said one day some people in suits came to visit the little shop. When they left his mentor looked very sad and ordered him to destroy the motor and other inventions in the shop. My grandfather used a sledge hammer to demolish every trace of the inventions. He said his mentor never explained why.

Having heard this story all my life, it is easy to believe that there is some conspiracy to suppress free energy technology. However, I also believe in the power of free information exchange. Other than cave locations, I have not found much to be hidden on the internet. It would seem to me that if free energy technology really was available, there would be some people somewhere using it. And they would write about it on the internet.

I still hold out hope. For now I will just have to be content with fanciful stories of how the inventions of Marconi and Tesla have been lost or suppressed. I know that we have minds today equal to theirs. If it was possible to do once, it will be invented again.

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