Crankshaft Seal Surface Repair

[dcooke007]

I have been present but not posted anything here in a while. Came across something that should prove useful to save otherwise non serviceable crankshafts. Note the pitted and damaged seal surface on this otherwise rebuildable Super Rat crankshaft.

This is a Speedi-sleeve by SKF. Timken also makes a similar product called Redi-sleeve.

As you can see the sleeve is just wide enough to center on the seal with a little margin for error. The sleeve can actually be installed after the engine is assembled. That might be a better option if you are not sure of the exact location of the seal surface.

Applied a bit of Loctite sleeve retainer and drove the sleeve on with the supplied tool.

The sleeve shoulder can stay attached if it doesn't interfere, but in this case it has to go. Sleeve is scored from the factory and I cut a slot in the shoulder before installing it on the shaft. Used my dremel tool with a cut off wheel. Grab with pliers and carefully peel it away.

Trued rebuilt crankshaft and we will see if my sleeve location measurements are correct.

Danny Cooke

[hodakamax]

Hey Danny, good report and good to hear from you.

Max

[efkruger]

That is an excellent fix for crankshafts. Too many crankshafts around that have some pitting from rust on those sealing surfaces. This is a great way to solve this problem. Hodaka Dave Rozier had told me about this some time back but I did not realize it was a product made by Timken and others. I have several crankshafts that I think I will repair this way.
Maybe someone could do a post on crankshaft rebuilding. I have a South Bend 10 inch heavy lath and a dial indicator. I just am not sure how to check alignment of the crank halves. Thank you gentlemen

[Bill2001]

Seal surface sleeves! Haven't seen or thought of those in years. They can work very well. What grade of Loctite do you use? We used to use Loctite Green, sleeve mount.

[thrownchain]

What happens when you cut off the "bell" and the sleeve isn't where it should be to seal correctly? Can you move the sleeve farther inboard if need be? I can see issues trying to remove the "bell" if trying to install without disassembly. And keeping the grindings out of places it shouldn't be. Be nice if they could come up with a similar solution for forks, but more issues with a sliding seal as opposed to a rotating seal.

[viclioce]

So Dan. I take it the sleeve gives a new surface on which the bearing can run, providing for a new smooth surface to which you can mate stock bearings? Or does it come with its own bearing to use as well? I guess I need clarification! Victor

[Bill2001]

You're usually able to see where the seal lips have contacted the sealing surface. If the seal marks are not visible, the seal contact can be found by measurement or temp reassembly. But simply placing the flange down on that bottom stepshould be OK. Google this repair sleeve and there should be more info.

[thrownchain]

The process is to renew the sealing surface for the seal, not for bearing surface.

[taber hodaka]

I think it is going to bottom out on the flange and be in the proper position to function. Victor if you look back at Dan's picture you will see the seal ect. -------Clarence

[dcooke007]

1. I used Loctite 609 green retaining compound to install.
2. I have not tried driving the sleeve further down the length of the shaft after removing the shoulder. With the shoulder attached you are pulling the sleeve over the shaft. After removing the shoulder you are driving the sleeve and I think it may distort seeing it is very thin....so might not work.
3. The sleeve is designed to install with out removing the shaft. I cut a slot in the drive shoulder prior to installing the sleeve on the shaft. So there would be no grinding debris. As long as there is room you just grab the shoulder and peel it off in a twisting motion.

Careful measurements and planning are require to assure success.

http://www.skf.com/group/products/seals ... index.html

Danny Cooke

[dcooke007]

Measured the left crankshaft seal and set depth adjustment rod to see where the seal would be located when installed in the engine case. I wanted to see if I had a little "room" to install the seal a bit deeper without blocking the bearing / seal lube passage.

You can see with the crank seal installed flush the lube passage, in this case, is not blocked. Also does not contact the crankshaft or bearing.

I installed new crank bearings and assembled the engines cases to check my work. Crankshaft is resting against the clutch side crank bearing as it would when fully assembled with the clutch installed. Crank seal installed just barely above the case. You can see the sleeve extends about a 1/16 inch above the outer edge of the seal.

I applied machinist spotting blue to the sleeve before assembling the engine cases so I could see where the inner seal contacted the sleeve. The inner seal lip pushed the non hardening spotting blue down the sleeve indicating the inner seal contact area.

Not exactly what I was shooting for but ended up with the outer and inner seal lips contacting the new sleeve. Technically that is all that is required but would have been nice if the seal was bettered centered on the sleeve. Failed to take into account the inner seal lip is not flush with the outer shell of the seal. Next time will not install sleeve quit as far onto the shaft. The SKF part number for this sleeve is 99068. The 125 engine will require a different sleeve and a different approach.
Danny Cooke

[Bullfrog]

Excellent review! You are a good educator Danny!
Ed

[squid on a 300]

And that Gentlemen is exactly why I send my engines to Mr. Danny Cooke for restoration!
Bob

[viclioce]

Great report Danny! Don’t know when I’ll need it, but at least now I know it can be done! Thanks! Victor

[dcooke007]

Ed,
Just sharing what I learned along the way. I enjoy the mental exercise and challenge of trying to keep these bikes putting along. Every salvaged part is a step in that direction.

Thanks for the the positive comments by all.

Bob,
Appreciate your confidence and will post pics of your completed engine.

Danny Cooke

[thrownchain]

Ok, since the repair piece doesn't have to be installed as far on the shaft as previously thought, does the bell still need to be removed? There looks to be ample room between the seal and the bearing so lubrication shouldn't be an issue.

[taber hodaka]

I don't think you could take the bearing off or the engine apart with the bell on.----Clarence

[thrownchain]

Motor apart most likely, bearing off the crank, probably not, good point. But as a "quick fix" you might be able to install as is.

[dcooke007]

thrownchain,

Removing the "bell" / drive shoulder is not a difficult operation. The sleeve is factory scored so it simply peels off. You just need to cut a slot in the driver shoulder prior to installing the sleeve.

The sleeve shoulder diameter is larger than the inside diameter of the crank bearing. With the shoulder attached the crank would not pass through the crank bearing. Even if I was installing the sleeve with an assembled engine there is not much space between the seal and the crank bearing. I think it would be best to remove the "bell" / drive shoulder.

The 125 engine is going to present some additional challenges since the left crankshaft diameter is the same for the seal and bearing surface. On the 125 engine the sleeve will require installation after the engine is assembled. Or....if the engine is completely disassembled might be able to install the left crank bearing on the crank, install the sleeve and then heat the engine case so the left crank bearing / crank assembly can be installed in the left engine case. This would only work if you have an oven to heat the engine case so the bearing just drops in with out much force. I gave up a long time ago on driving / pressing in engine bearings. I just use a large toaster oven and heat the cases to 325 degrees for 20 minutes and the bearings drop right in. Again, I have not attempted this on a 125 crank...yet. Just my thoughts at this time.

Danny Cooke

[dcooke007]

Making progress on Bob's engine.

Danny

[Hydraulic Jack]

Frankly, I would not leave the bell on the sleeve even if it doesn't interfere with any rotating parts. As mentioned,the bell is pre-scored for easy removal. That means there is a stress riser built into the sleeve at the bell. Installing the sleeve knowing that there is potentially a stray, vary hard, piece of metal debris inside the bearing system just waiting to detach and eat my seal would make me uncomfortable. It takes only a few second to remove it, why leave it there under any circumstances?

[thrownchain]

I did some research into Speedi Sleeves. Seems you can only buy the kit which will cost me $52 more or less. You can't buy just the sleeve part which would be a cost savings since I would already have the tool. So every repair I want to do adds $52 to the cost, not that it wouldn't be worth it. Have to think it over.

[AKwombat]

Hopefully this information will be useful to others. I have several model 94 crankshafts with Speedi-Sleeves installed. Hodaka Dave did the first one and I have installed a couple more. Recently installed a 99078 Speedi-Sleeve with #3 Permatex under it.

This requires some measuring to ensure correct positioning of the sleeve so it lines up properly with the seal. Removing the drive collar from the Speedi-Sleeve was necessary in this installation, as leaving it on would have prevented the left bearing from being able to float on the crankshaft. The left case half was heated to 325F in an oven and the bearings and crankshaft were installed in the case. After cooling, the seals were installed.

This changes the engine assembly sequence a bit, but seems like a good repair and makes an otherwise unusable crankshaft usable again.
Chris

[dirty_rat]

With this installed on a model 94 crank, how would you change the ignition side bearing if you ever had to? Seems the sleeve would keep the bearing from coming off. On the early 100 cranks it doesn't look like a problem as the bearing is a larger diameter than the seal area.

[AKwombat]

Dirty Rat - I had one speedi-sleeve on the magneto side of a 94 crankshaft that leaked air during the engine leak down test, resulting in test failure. I disassembled the engine and removed the speed-sleeve by using a splitter type bearing remover behind the left bearing. This pushed the speedi-sleeve off with the bearing, no problem. That sleeve did not have any sealant under it. After that I installed the speedi-sleeves with #2 Permatex to prevent air leakage. The speedi-sleeves are not re-usable, so reassembly included a new sleeve. I have also removed speedi-sleeves by very carefully scoring them with a cut-off wheel, being careful not to get into the underlying shaft. Then using a knife or chisel, peel a corner of the sleeve up, grab it with pliers and peel it off. Similar method to removing the installation flange that the speedi-sleeves come with.
Chris