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While fitting the oil slinger and woodruff key for the prop hub I bent the slinger very slightly. I stopped and removed the key and slinger. I was able to bend the slinger back into shape. I left the prop hub in the oven and placed the crank back into the freezer. Can I re use the slinger? I also sent am email to Sonex.

Sonex replied fast. They told me to put it on and put the crank into the case half to check for clearance. I put the assembly into the case and it looked good. They said they could not say if it would perform as intended and would not damage the engine if it did not rub the case. It was up to me I decided to go ahead and use it. The crank was in the freezer for 7 more hours then I heated the hub at 465 for 1.25 hours. Then I attempted to slip the hub on. I did it right next to the oven. It only went on 1/2 way. So I sent Sonex Tech Support an email about my problem. Hopefully there is a solution that will make my life easy. Has anyone else had this happen to them?

I had to remove my prop hub & timing gear due to problem with the gear mesh with the cam gear. Sonex said to press it off. Fortunately I have access to a hydraulic press and removing it was not a issue. Care must be taken to get proper alignment and catching the parts as they separate. I think you had the problem that most ovens do not get as hot as the dial indicates. They are used for baking cakes and such. You will have to get the hub much hotter. As you slide the hub on the part in contact with the shaft is cooling so you must have plenty of latent heat built up in hub to keep it expanded until fully in place. Also the shaft is expanding by being heated. Get it HOT - work QUICKLY.

Please keep us informed about your assembly and any problems you encounter.

I think I should have let it "bake" longer. I have a commercial restaurant oven and confirmed the temperature with a digital BBQ thermometer.

You will have to press it off. I had the same thing happen on mine but mine was stuck a little more than 1/4 of the way down. I made the mistake of installing the gear and not re-freezing the crank before installing the hub. The heat from the gear warmed the crank up enough that it no longer was big enough to slide on to the hub. The second time I did it the hub slid on with only finger pressure.

You will need a hydraulic press to remove it. Do not press it on the rest of the way. There are service bulletins on the aerovee specifically prohibiting that unless it is within the last 1/8" of seating. I would contact Sonex for the specifics of how to do it but for mine I supported the prop hub with some blocks on the press and had the crank hanging down between the supports so there was no pressure on it. I used a deepwell socket down the bore of the crank to push on with the press. It took surprisingly little force for it to come back off.

When you go to do it the second time, crank the oven up to 500. Also, get a oven thermometer from a kitchen store and put it in there with the crank to make sure it is getting up to temp.

Keith
#554

Sonex said to press it off and give it another try. So today I went to a friends house to remove the hub from the crank shaft. We used a 20 ton press. We set the hub on brackets to hang the assembly. Then used a socket and 1/2" drive extension down the center hole and used it to push the crank shaft out of the prop hub. I held on to the crank like it was a baby. I did not want it to fall on the floor. I took the parts home and will get a chance to redo the prop hub after thanksgiving week.

Had the same problem when I did mine, on 1/2 way and stopped. once that happens your done IMO, and then the call to Sonex.
Joe N answered my call and felt it was a "not heated enough issue". First time around I installed the gears first, rechilled the crank
heated the hub for 1 1/2 hrs in preheated 500 degree max setting kitchen oven. Joe said they do the cranks a few at a time and
they slide right on. Pressing the hub off was easy enough and the the second attemp we heated the hub upwards of 2 1/2 hrs.
Joe was right, the hub went on with ease. It was a good feeling when that sucker went on!
Lot of heat, Good luck!

Had a surprise today, when I went to install the rocker arm assy's the manual says to put the rocker arm shaft in place to
make sure the cylinder studs do not contact the rocker shaft and if they do to trim them down. Bad time to do this step as I had to layer
protection in the top of the cylinder heads to keep metal shavings out of my nice clean engine. would have been better
to mock it all up and check the clearance before final assy of the cylinders, would be much easier to have trimmed the studs then.

I finally had a chance to get the prop hub on the crank shaft. I put the crank into the freezer for 2 days and baker the hub in the oven for 4 hours at 512 degrees. I got everything setup in the kitchen this evening and the hub just slipped right on. I just gave it a tap with the palm of my hand and it bottomed out on the oil slinger. I put the bolt and bushing in with an impact gun and am letting it cool until the morning so I can remove the bolt and lactate and torque the bolt.

Wow I messed up the photos. Here they are.