propbuster

My Feedback: (1)

Hi Guys, I've got a plane that needs more clearance between the fuselage nose and the spinner backplate. Short of shimming the engine mounts away from the firewall or cutting back the fuselage nose blocks and recovering it, How unsafe would putting say, a thin nylon washer/spacer between the thrust washer on the engine and the spinner backplate be? Would I be looking for problems with props loosening up? Thanks, Tim

Campy

My Feedback: (1)

You SHOULD be OK using a soft metal washer as a shim. MAKE SURE the hole in the washer is the same size as the crankshaft AND the outer diameter is the same size as the thrust washer. If the crankshaft hole is larger there is a very real possibility of the washer shifting and causing a bunch of vibration.

The reason I say soft metal (aluminum ) is that the thrust washer will be able to bite into the metal without compressing the washer where the nylon washer may compress and loosen in flight.

Zippi

My Feedback: (10)

propbuster,

I've used real thin gasket material that comes in a carb kit. Works really well.

propbuster

My Feedback: (1)

Zippy, I'm trying to gain about 1/8" more clearance, so I think I'll need the metal washer to get that.
Campy, Good point about the nylon compressing, Also, what do you guys think about filing thin grooves in the side of the washer that will meet the spinner backplate to bite into it like the thrust washer is supposed to do? Thanks Guys

daveopam

My Feedback: (9)

I don't have the same problem but have a solution. On a Saito72/82 there are not enough threads to use a thin prop. In other words the prop nut will not tighten up the prop before the threads run out on the crank. I took an old broken spinner and cut the back plate into a washer. It works great. Can be seen in pic.

David

Redback

I too have used the cut down cente of a spinner as a washer without any problems.

Terry

scratchonly

Cut a piece of 1/8 AIRCRAFT ply to the proper size; a 1" hole saw works fine. Glue some 320 wet and dry sandpaper to both sides with med CA. TIGHTEN THE NUT. I have a plane with a 91 fs that flys every day with this washer. Good luck.