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Lycoming O-360 A3A prop spacer

trackdom

Well Known Member
Hi,
Time has come to look for the prop spacer . I know it’s a 2,25” one, but I heard A3A lycoming has long bushings . Does it mean prop spacer is different from standard one?
I am waiting answer from Saber Manufacturing , and I am trying to get informations from a builder having A3A lycoming .
Thanks
Dominique
 
I might be wrong, but I think the A3A is made for a pusher configuration. The only difference is those different bushings. They can be removed and the tractor configuration bushings installed. I did that on my first airplane (RV6) as suggested by Aerosport Power. He told me how to remove the long bushings, which I sent to him and he gave me the correct bushings for my application - no charge.
 
per Lycoming SI 1098G the bushings on an A3A are a bit longer than the more common engine variants.
The long bushing (72063-S) on the common engines measure 0.90" from the shoulder to the end.
Your bushings (74248-S & 74249-S) measure 0.98" from shoulder to the end. The diameters of the bushings are similar in all cases between the engine variants
One easy solution might be to file 0.08" off each bushing (as it doesn't affect the internal thread), than you could use any prop extension out there.

Additionally, I quickly measured the spacer supplied with the Sensenich prop Vans specifies for 360 engines. All shouldered holes are milled 0.506" deep & are same diameter all 6 locations.
 

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Scott,
I think I can use A3A in a tractor configuration. Changing bushings is not that much easy .
Thanks for your help.
 
Yep. I used the A3A on my first RV6. I did change the bushings and it wasn’t hard to do. The guy that owns AeroSport Power (I forget his name - locally famous here) told me how to do it. Filing it should work too. Try to make sure you stay square with the file.
 
Hi,
Time has come to look for the prop spacer . I know it’s a 2,25” one, but I heard A3A lycoming has long bushings . Does it mean prop spacer is different from standard one?
I am waiting answer from Saber Manufacturing , and I am trying to get informations from a builder having A3A lycoming .
Thanks
Dominique

I just installed a new engine/prop in my -8. I pulled out an A4A with a FP prop, and since I installed a CS prop, so I’m not using the spacers. If you are interested in used (350 hours) send me a PM and I can take some measurements for you. Pretty sure I have the size shown in the drawings for a FP prop.

Brian
 
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