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doug

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Where would a guy like me find a NEW prop hub for an A65 part number A3746? I bought one 4 years ago but don't remember where. Thanks
 

doug

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No luck. They suggested Fresno. Have to wait till they are open.
 

NC1776

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Ok, will give this a try again, There were two runs of prop hubs made one was the original for continental that were pretty easy to identify as they were Type I cad (silver) and came new in a coffee can with the bolts, crush plate, and hub. You actually had to open the can just like an early coffee can and I figure that is exactly what they were. In the late 70's you could find a few around but not many. By the late 80's they had pretty well dried up. Now to find a new legal original Prop Hub would be like finding gold in the hills. If you find one then you can expect to pay a very high price for it. I would pay $1000.00 if anyone had one. They did not have any serial numbers or part numbers stamped into them. Only the timing marks. However there are a number of good Yellow tagged ones available from around 495. to 595.00.
The other "New Ones" and I expect what you are refering to are one of the Type II plated ones (Gold) that were produced around 1980 by Lou Libbie Robert Webers father in law and the founder of what is now Fresno Air Parts. These hit the market with a storm and I bought a bunch of them from Lou for $125.00 each back then. They were brand new and really looked good. Came with the bolts, nuts and crush plates. However there is always a down side. They were never FAA/PMA approved. To be honest back then we really did not care we just put them on. There was one minor problem with the new Type II cad ones and that was they were about 1/2 of a degree differance between them and the crankshaft. So we ended up taking them and lapping them to the crank each time with valve grinding compound. They ran fine after that and lasted for many years. I do not know of anyone who still has any of those left anymore and last time I did find one it was $600.00 and that was 10 years ago.
So to make a long story short most likely unless you get really lucky the only one you are going to find will be either a used one like the one on Ebay which could be cracked. Usually between the keyway and the large hole on the flange, or a yellow tagged one. I have 1 left that is currently yellow tagged and Type I cad but I am waiting to see if a friend is going to need it and should know in a few days. I know he needs the bolts and crush plate already. You cany buy the bolts and the crush plate from Aircraft Spruce for about 1/8 of what some other shops get for them but again most are not approved parts.
So if you are in a bind for one let me know and if my friend does not need it I will sell this one for a fair price. Currently his mechanic is trying to get the old one off of his old engine without distroying it.
Dave
 

Will42

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Dave; that's interesting information. I learned a good deal from your post and that's the main reason I'm on here.
Since you mentioned it, how is the best way to get a stuborn hub off without damage. The "Barn Cub" hub seems to be stuck pretty good and with less than 200 hrs. on it, I sure don't want to mess it up.

Will/RW
 

NC1776

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The biggest battle in getting an old prop hub off is the snap ring closing up and then the nose peice comes out. Now you have two peices instead of one. You can soak them, you can heat them but in the end the snap ring is the downfall. The little trick is to leave the prop on for leverage and then make a little tool that is about 1/8 inch thick and the exact width of the snap ring opening in the normal position. I usually use a lot of WD40 the night before on both the crank and nose. However after getting the hubs off I have never seen the WD40 much more than 3/4 of an inch from the flange so not sure exactly how much good it did. However it does help with the snap ring. Put a bar through the holes on the nose of the flange and as big and as close to the hole size as you can get. It has to be tempered as raw steel will just bend. Tool steel is great if you can find it. I have a ventage 1/2 breaker bar that is older than I am and that is very old that is not tapered at the end. put it through the hole and then get the longest peice of pipe you can find to put over it. Protect the prop at all cost with padding but make sure it is against something solid with plenty of padding. A good sholder of a friend with a packing blanket works good. Remember that little tool, now it becomes really important as you need to push it in between the hub and the nose peice and in between the ends of the snap ring. If I am by myself I usually use either a hose clamp or rubber bands to hold the peice of metal in place. All you are trying to do is keep that darn ring from closing up when you put the pressure on the bar and it turns against the snap ring to pop the hub loose. I have never had one beat me yet by doing it this way and never hurt the hub or prop. If you try to use the prop bolts without the prop and a bar between them to hold the hub you will warp the hub most likely. I have never had to use heat and I have had some that people had tried for weeks to get off. If the motor is off you can pad the prop I mean really good and have the bar just a few inches above the blade so you are pushing right down towards the floor. If the metal tool pops out, stop right there and start over do not continue and try to turn it as all that will happen is the two peices in stead of one. If you do it right the hub comes lose in about 1/4 turn after the nose peice becomes really tight agains the nose peice.
If that happens there is a real trick to getting the two peices back together again. Thats chapter two. Chapter three is how to remove the nose on purpose when someone has dinged it up so bad it needs replacing.
One of a thousand ways but works for me.
Dave
 

Will42

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Thanks David; good info here. Our engine is off; I haven't tried the hub but I think Jarred did when he was disassembling the Cub; not sure what he did but I know the hub is still tight to the crank. I will definitely use your ideas.

Will/RW
 

longwinglover

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Dave's information is really good. There is also a really good article with pictures and tool discriptions/drawings in the Nov/Dec 2004 Cub Club newsletter ( # 125 ) that is equally informative. I believe this article was also reprinted in EAA Vintage magazine.

John Scott
 

doug

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Thanks Dave for coming back to the site and for the offer. I found one from Don's Dream Machines this morning. I hope he knows the same information that you do. It is used and he said it was in very good condition. What causes them to crack? Do you know? This last one was "brand new". A gold one. It lasted only 4 years and 400 hours. The one before this one lasted at least 3000 hrs. per log book entry. + - "?" It was a silver one. Someone suggested that I fly it anyway. "What would happen?" I told him the prop would eventually fly off. Because I don't like a cracked one and was looking for an excuse. I can see it eventually wearing out the crank. Am I correct? I noticed that the gold one didn't fit the crank so I tried to fit it with valve lapping compound but felt like it was a lost cause so I installed it anyway. I thought maybe it was made that way on purpose so it would be easier to remove. If the one I get is the newer style what is your method of lapping it? After they are all used up what are we gong to do? Is there a way to repair them?

In referance to the CUB CLUES article, I tried to make the socket attachment that they talked about but was unable to drill the hole in it cause it is to close to the edge. Using a long 5/8" grade 8 bolt and a long pipe worked fine for me. Also instead of using WD40 try MOUSE MILK. Seemed to work for me in the the old days before it broke.
 

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