Author: Mike

Posted on

Adjusting Pinion Preload on a Dana 30

Adjusting Pinion Preload on a Dana 30

Jennifer’s Jeep Cherokee has been riding a bit rough lately. It has had a growl and a vibration at speed. We tried swapping drive shafts and rotating the tires but the noise and vibration was still there.

A close inspection showed some play in the pinion shaft in the front axle. I knew form the experience with my Jeep that this could cause a vibration.

She really did not want to spend a lot of money fixing up this gear set since she will be installing a set of 4.11s in the next few weeks. She needed just a temporary fix to get by.

I looked in the factory shop manual for the preload adjustment procedure and it mentioned a crush sleeve. I thought that I could just crush the sleeve a bit more and take out the slop. I put a big pipe on my pull handle and cranked on the nut. The nut turned but the end play stayed the same.

A bit more research made me realize that there is no crush sleeve in a XJ Dana 30. I am not sure which front axle the shop manual was referring to. But, I was sure I had succeeded in stripping the nut.

When I later pulled the nut, sure enough, the threads of the nut were nicely embedded in the pinion. I was glad the nut stripped and not the pinion. It took a few minutes with a pick, but I was able to clean the threads.

To adjust the pinion preload, I began by removing the wheels and tires. Next I removed the brakes and the center axle nuts. I could have left the axles in the hubs but it was easier to handle them separately. I used my sacrificial bolts to separate the hubs from the knuckles.

I then removed the hubs and axle shafts. I then separated the tie rod on the driver side and let it hang down out of the way. I then removed the cover and drained the fluid.

I removed the carrier bearing cap bolts and after noting he marks, carefully removed the caps. I was getting ready to set up the spreader on the case to remove the carrier when Jennifer who was removing the drive shaft tapped on the pinion. The whole carrier fell out almost on my foot! So much for needing a spreader. I guess all the bearings are pretty worn. The carrier as well as bearing s will be replaced when the new gears are installed so I just reused all the parts anyway.

With the drive shaft out of the way, I removed the pinion nut. Sure enough it was stripped. With the yoke off, I tapped the pinion out the front. I pried out the seal and collected he slinger, bearing and shims.

I set the pinion back in place and removed a .010 shim. It was still too loose. I pulled another shim and it was still too loose. With .030 shim gone it felt about right. With any less shim, it was way too tight, so I settled on a shim pack and put it al back together.

I made sure it all felt OK with the axles back in before I installed a new pinion seal. The seal and the gear oil were the only expenses for this job. I used an old pinion nut from a spare axle behind the barn.

I used black silicone for the front cover seal and left the tie rod off until Jennifer had refilled the housing with gear oil before putting it back in place.

A quick test drive showed much less vibration and the dragging growling feeling was gone. Hopefully the bearings will last a few more weeks.
[phpbay]dana 30, 10[/phpbay]

Posted on

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.

Posted on

Cowan Railroad Museum

Cowan Railroad Museum, Cowan, Tn

After scouting Iron Gap Road, we stopped for brief tour of the outdoor exhibits at the Cowan Rail road museum. It was near dark and the museum was closed, but it was still fun to get out and walk around the old trains and climb on the steam engine.

Cowan is the place where the railroad begins it climb over Mont Eagle mountain. Even with a tunnel through part of the mountain, it is so steep that they have to add extra engines to make the climb. Cowan is where they store the pushes and hook them up for the climb to the top of the rock.

The museum is located right on the main road in downtown Cowan, right beside the rail road tracks. No trains came by while we were there however.

At one time it was possible to take a Jeep to the tunnel entrance. But, since it is on CSX property, I doubt that you can safely make the run anymore.

Across the street, there is a Texaco station with a couple of antique cars visible inside. The museum is open May through October, so we will have to return when it is open and check out the inside.

Posted on

Abandoned McDonald Elementary School

Abandoned McDonald Elementary School

A tour of the abandoned elementary school in McDonald, Tn

Jennifer arranged for us to tour the old school building in McDonald. This is the school where she received some of her early education. It was abandoned years ago when the boiler failed and is scheduled for demolition.

Many memories haut the hallways. The school was abandoned abruptly in mid year and students were displaced to Black Fox and Prospect elementary schools. The school has most recently been used as a community center, but with no electricity and no running water, there has not been much use made of the building.

The roof has not been maintained and with no heat, the structure has begun to severely decay. The once beautiful hardwood floors in the hallway have buckled and the doors are falling off their hinges. Paint is peeling and the ceilings are falling in. Most of the windows are broken.

Many odd reviewers of the bright days of elementary school remain however. The paintings of Charlie Brown and Lucy marking the boys and girls restrooms are still colorful. The fact that the restrooms are in the basement with and can only be accessed by stairs may be clues to why the building was abandoned.

The old cafeteria, also located in the basement, was littered with an odd collection of tables, chairs yard sale remnants and weird cans of processed food. There was a very nice industrial refrigerator there in the midst of the junk however.

Many of the paintings on the walls of the classrooms survive. There is a train representing the moths of the year in one room and a row of apples lining another room. In one pile of books, Jennifer actually found one of her old school books. It had her name still listed in the front of the book when it was assigned to her.

One room has a unique feature. It has an elevated section with a tree mural painted on it. It was called the tree house. The fifth graders could climb a ladder and sit there and read.

The auditorium seemed the best preserved room. The stage was still in good shape and less debris cluttered the room.

At some point someone, I hear it was the Ruratain club, spent a lot of money to add electrical wiring to the building. Apparently the project was never finished as there are big empty breaker boxes hanging on many of the walls. The electricians made no effort what so ever to make the installation look nice however. There is ugly PVC conduit exposed on the walls and the holes where the came through the walls are ragged and unfinished. In some ways it looks like they had to have worked extra hard to make the conduit runs so ugly.

In the basement there is a huge Ronan switching panel connected to the large emergency generator outside. It looks like they were well prepared for an extended outage.

Outside, the playground is nothing more than an asphalt pad. There is a set of monkey bars in the woods surrounded by briars.

The gym is a huge metal building obviously built much later. It appears to be in good shape. However there is an odd drainage problem apparent wilt the building. The grade slopes toward the front where there is a huge sidewalk. There is no provision made for the water to drain under the sidewalk so it just dams up there in a heavy rain. There is evidence that the water collects several inches deep at the corner of the building. The side panels are rusted and there are stories of water entering the building. I can’t imagine what the builders were thinking.

Posted on

Iron Gap Road Scouting Trip

Places to Ride in Tennessee

We read on a few internet forums about a road called Iron Gap road. We finally found it on the map and saw it was between Cowan and Winchester. There are a lot of interesting things to see in that area so we thought we would make a scouting run before loading up the Jeep on the trailer and making a full scale assault.

We got to Iron Gap by taking the road through Cowan and then taking the new 64 bypass just outside of Winchester. We then took HWY 16 due south to the top of the mountain.

Just at the top there is a fire tower visible. We turned there and hit Iron Gap road beside the Keith Springs Community Center. We saw some trailers parked there so our plan is to park ours there when we return.

The road starts out paved. But just before you get to a nice farm house, the road veers right and becomes unpaved. There is evidence of an old gate here. The trail starts out as a nice unpaved road with a few shallow mud holes. Janice drove her stock XJ while Jennifer navigated. I sat in the back.

The road followed the ridge for about three miles. Then as it started down the mountain, it stared to get a bit rockier. I got out a spotted Janice as she drove over some of the smaller rocks. As we neared the valley floor, the rocks got bigger and the hill got steeper. After walking a particularly tricky section, I decide that we should turn around. If we had had another Jeep with us or some recovery gear I might have tried it, but it looked too risky to try coming back up alone.

Janice was tired from the drive over and the bumpy ride in so I turned her Jeep around and headed back up the hill. We posed for a few pictures on the small stair case climbs. It definitely looks like a place we will have to return to with the off road Jeeps.

Back on the pavement, I had hoped to return to Cowan via the Turnpike road. We found what I think was the road, but it was marked private by a hunting club. So, we elected not to risk it and headed back to Cowan the way we came.

We stopped for a quick tour for the train Museum and to check out the old cars in the Texaco across the street. We then headed up the mountain to climb the overlook rock near Sewanee just at sunset. Since Jennifer had never seen the campus at University of the South, we made a small detour through the campus. She did not see much in the dark however; just enough to want to come back.

UPDATE: Return to Iron Gap