Author Topic: My Saito .40 - Worn ring? (Read 2318 times)

Terry Caron · « **on:** May 21, 2016, 03:01:48 PM »

My Saito .40 turns a 12-4 APC at 9.5K on 15/65/20 fuel, which seems low.
This is very subjective but, turning a prop slowly by hand, there doesn't seem much compression.
Do 4-S normally feel "soft" or is it likely I have a worn ring?

Terry

Robert Zambelli · « **Reply #1 on:** May 21, 2016, 04:07:27 PM »

Nothing to worry about.
I've got around 20 SAITO engines and they all will occasionally behave like that.
It's normal to have some leakage past the ring - that's how the bearings and valve gear get lubricated.
And, I've never had to replace a ring or bearing on a SAITO.

Bob Z.

proparc · « **Reply #2 on:** May 25, 2016, 03:03:20 PM »

Quote from: Terry Caron on May 21, 2016, 03:01:48 PM

My Saito .40 turns a 12-4 APC at 9.5K on 15/65/20 fuel, which seems low.
This is very subjective but, turning a prop slowly by hand, there doesn't seem much compression.
Do 4-S normally feel "soft" or is it likely I have a worn ring?

Terry

Seems low? A 40 turning a 12" prop at 9500 seems pretty darn good to me. You can certainly go flying with that.

Terry Caron · « **Reply #3 on:** May 25, 2016, 03:10:41 PM »

I appreciate the encouragement, Milton.
It's my first 4-S, the older Mk 3, bought used, so I don't really know what performance to expect.
I'm thinking of a Brodak P-40B, a Pathfinder or Cardinal for it.

Terry

Author Topic: My Saito .40 - Worn ring? (Read 2318 times)

Terry Caron

My Saito .40 - Worn ring?

Robert Zambelli

Re: My Saito .40 - Worn ring?

proparc

Re: My Saito .40 - Worn ring?

Terry Caron

Re: My Saito .40 - Worn ring?