upgrading crankshaft oil seals

[Nickt919]

Watch the videos. They give a lot of info on balance and true…

You will need a few tool to do this.

A drill press is necessary. The cheap Harbor Freight press and dial indicators work sufficiently well for what we do.

Once you have a good idea what it takes ask questions here..

If you need help in tearing down an engine there’s good info on this site..step by step.

I learned from this site and have acceptable success with my engines. I have paid my learning dues though. I tore up some stuff along the way. YMMV..

 

[Deleted member 35519]

Thanks for the info. Great learning experience.

 

[Deleted member 35519]

Watch the videos. They give a lot of info on balance and true…

You will need a few tool to do this.

A drill press is necessary. The cheap Harbor Freight press and dial indicators work sufficiently well for what we do.

Once you have a good idea what it takes ask questions here..

If you need help in tearing down an engine there’s good info on this site..step by step.

I learned from this site and have acceptable success with my engines. I have paid my learning dues though. I tore up some stuff along the way. YMMV..

So I have removed everything on one crank including the gears. However I have had a bad experience trying to knock out one of the pins that mounts the 10t sprocket and clutch. All Woodruff keys have been removed. I'm going to have to get some wood and trying making an aluminum thing such as Build Break Fix It describes in his dissasmbly bible video on YouTube. It doesn't seem the rod wants to knock out. A new friend that sold me the Minarelli bike yesterday mentioned he spent $100 at harbor frieght for a hydrualic press and you can get away with using them on more stubborn ones. But you must be very catious not to stress the aluminum castings of the crank case.

Either or I'm stuck there right now. Also I ran into one other issue using the crank removal tool on the small gear (whatever people call it) on the crank side. I used the bearing ball to remove the gear and now it's seized in there lol. I tried to heat it up, everything with a propane torch to remove it, haven't tried oiling and removing it yet. It may just need a good Neanderthal wack.

I'm looking forward to getting all these cases open, it just seems that these 10t and crank arms are cancer to get out. Their in there pretty strong.
I'm rather happy that i found this person selling a Skyhawk Don Butler Ported Minarelli. Now I just need to match my CMB case. Seems both cases are identical to the classic Skyhawks. I have already ported the top cylinder head of the CMB minarelli head with a carbide dremel bit. I just need to open the transfer wells a bit. Then port the bottom crank once it's open.

 

[Deleted member 35519]

california motorbikes minarelli head to the left (needs more work) and the Don Butler to the Right.

 

[Chainlube]

View attachment 207745
View attachment 207744

So I have removed everything on one crank including the gears. However I have had a bad experience trying to knock out one of the pins that mounts the 10t sprocket and clutch. All Woodruff keys have been removed. I'm going to have to get some wood and trying making an aluminum thing such as Build Break Fix It describes in his dissasmbly bible video on YouTube. It doesn't seem the rod wants to knock out. A new friend that sold me the Minarelli bike yesterday mentioned he spent $100 at harbor frieght for a hydrualic press and you can get away with using them on more stubborn ones. But you must be very catious not to stress the aluminum castings of the crank case.

Either or I'm stuck there right now. Also I ran into one other issue using the crank removal tool on the small gear (whatever people call it) on the crank side. I used the bearing ball to remove the gear and now it's seized in there lol. I tried to heat it up, everything with a propane torch to remove it, haven't tried oiling and removing it yet. It may just need a good Neanderthal wack.

I'm looking forward to getting all these cases open, it just seems that these 10t and crank arms are cancer to get out. Their in there pretty strong.
I'm rather happy that i found this person selling a Skyhawk Don Butler Ported Minarelli. Now I just need to match my CMB case. Seems both cases are identical to the classic Skyhawks. I have already ported the top cylinder head of the CMB minarelli head with a carbide dremel bit. I just need to open the transfer wells a bit. Then port the bottom crank once it's open.

6 bolts on the clutch side and 2 on the mag side and the whole thing breaks in half. Use a putty knife to slowly pry it apart. Put the mag nut on with just a couple threads left and tap the end of the crank to get it to go all the way.

 

[Deleted member 35519]

Oddly tried the same thing besides the putty knife. I'll try again and let you know how it goes lol ...

 

[Nickt919]

Some are stuck tight

*Rubber mallet
*Nut on sprocket shaft
*Nut on magnet shaft
*Some heat helps but it may ruin seals
Tap the nuts back and forth.. not left field whacks or it’ll booger the threads. The metal is soft.

Once I get it split I change all 4 bearings and use emery cloth to get a snug slip fit on the shafts in the bearings to make future splits easier.

 

[Deleted member 35519]

Some are stuck tight

*Rubber mallet
*Nut on sprocket shaft
*Nut on magnet shaft
*Some heat helps but it may ruin seals
Tap the nuts back and forth.. not left field whacks or it’ll booger the threads. The metal is soft.

Once I get it split I change all 4 bearings and use emery cloth to get a snug slip fit on the shafts in the bearings to make future splits easier.

My situation was stupid. All i had to do was remove the arm that holds your clutch cable as it was pressing against the clutch spring inside the case lol.

 

[Nickt919]

My situation was stupid. All i had to do was remove the arm that holds your clutch cable as it was pressing against the clutch spring inside the case lol.

When setting up an engine that has to be checked.
Ive had more than one engine come that way.
The engine was not gonna run or run right with the clutch engaged this way.
I’m not sure why they make the threads long enough to hit the shaft when fully threaded but they do.

Screw it in where the threads are as deep as the case thickness at the hole and lock it with the lock nut.

 

[Deleted member 35519]

When setting up an engine that has to be checked.
Ive had more than one engine come that way.
The engine was not gonna run or run right with the clutch engaged this way.
I’m not sure why they make the threads long enough to hit the shaft when fully threaded but they do.

Screw it in where the threads are as deep as the case thickness at the hole and lock it with the lock nut.

I suppose cutting it down would resolve this. But some sources say its to adjust the tension of the internal crank shaft as i find highly unlikely due to it just being a bolt rubbing against the internal components.