1974 Super XLAO crankshaft bearing replacement

[nimrod55]

I'm rebuilding a Super and the clutch side crankshaft bearing was bad. Here is my saga.

This is the best video on Youtube. www.youtube.com/watch?v=CwsJivlU8zc&t=465s

I removed the connecting rod cap and saved the 31 needle bearings. Took off the crankcase box, removed the 2 screws, and pulled the bearing/crankshaft assembly out of the drive case.

I don't have a hydraulic press to press the bearing off the crankshaft. I did get the old bearing off without damaging the crankshaft but it involved a piece of angle iron, a welder, a 2 jaw puller, a Dremel cut off tool and a chisel. I wouldn't wish this method on anyone so I won't go into more detail.

NOS bearings are listed on Ebay for $30. I took the crankshaft, remains of the old bearing, and the drive case into the local bearing and seal shop. They measured everything and came up with a replacement bearing for about $6. I won't list the part number because I didn't realize that the slot cut in the outside of the outer race was important until I tried to put in the retaining screws. At this point I had already pressed the bearing onto the crank and into the drive case. I'm going to put it together without the retaining screws rather than pull it apart and get a bearing with a slot. Get a new bearing with a slot.

I put the bearing onto the crankshaft by putting the crank in the freezer for a few hours then applying a bit of oil to the mating surfaces and heating the bearing with my heat gun. I was ready to tap the bearing on with the right size deep well socket but it slid right on. Same method to put the bearing/crankshaft assembly into the drive case.

It's almost impossible to get an NOS clutch side seal so I ordered a Dichtomatik 0609318TC off the internet for about $5 but had to order 3 to get free shipping. Anyone need one? It fits a bit tightly on the crankshaft but I'll try it anyway. The flywheel side seal is the same as the one on both sides of an XL12 and is readily available.

For my next trick I'll try to get 31 needles to stay put while I put connecting rod and cap back around the crankshaft. A bit of grease helps them stay put. It's very important to get the cap back on the same way it was before. Mine has a mark so you get it right. You could make your own mark with a Sharpie to help you keep it straight.

  

[xl130]

Great job. I’ll be interested in how the crankshaft works out without retaining screws.

It will either end in catastrophe or run forever!!

[blythkd]

I'll bet you never know the difference.

[nimrod55]

There is a guy on Youtube that does a video on replacing the bearing on a Super and it looks like he's not using retaining screws. There have been no reports of his death so maybe I'll be OK.

There is almost no room for that bearing to slide out of the drive case when everything is put back together.

[drater]

Did they at least supply a bearing with the proper internal clearance ?

[nimrod55]

The new bearing only went on after cooling one part and heating the other. I don't think it will move. It seems to be correct. The thickness is also correct.

Putting the connecting rod and cap back on the crankshaft was almost as tedious as when I put the gears, bearings, and thrust washers back into the lower unit of my outboard motor while working through the hole for the prop shaft and bearing carrier. Once I got the pieces in place I had to slide in the prop shaft and carrier without disturbing them.

You need to determine the orientation of the piston. Most other engines have the gaps in the rings offset but not Homelite. The gaps line up and there is a little bump in each piston ring slot to ensure they stay there. The gaps and bumps go on the opposite side of the cylinder from the exhaust port.

You also have to determine the correct way the connecting rod and the cap go together. The cap only fits correctly one way since the mateing surfaces are not identical. I used a Sharpie marker to mark them so I could be certain to get it right in the heat of battle.

I applied a very thin coat of grease to the bearing surfaces of the connecting rod and the cap. The bearing needles stuck to the grease, 16 in the cap and 15 in the rod. A tweezers has been added to my mechanics tool set. Grease on the sides of the cap caused it to stick to the crankshaft while I put on the crankcase box. I had some 6 inch long twist ties that I carefully threaded under the cap. I used them to hold it in place while I lowered the connecting rod and piston into place and put in the screws that held them together. Then I used a flashlight to check that none of the 31 needles had come out during assembly. Whew.

[nimrod55]

I finished putting it together. When I bought it The carb was off it and in a bag . It was a Walbro carb but the check valve was bad. I dipped into my 1 and 1/2 XL12 parts saws and came up with a Tillotson. It fit with a few modifications.

So, I fired it up and adjusted the mixture screws. It runs good and strong. The bar oiler worked so I installed the 22 inch bar and chain it came with. It pulled the chain just fine so the clutch is working. When I went to put on the air filter and cover I discovered that the bracket they fasten to is different from the XL12 one that I scavenged from the XL12 parts saws. The bracket was the only part that was missing when I got the saw. I have to get a bracket. Then I will try cutting an actual log but I think we have a winner.

[jeremy]

There is a replacement bearing and seal for this application. I found them both from SKF. Homelite # is 58190. The SKF crank bearing # is a 6203 Jem. The seals that are homelite 12228 A, SKF # is 6119. It is a double lip seal, but it works at half the cost of a NOS seal on Feebay.

[jeremy]

I also found another seal that replaces the homelite #12282. It is a Timken # 253747