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Engine basics => Four strokes only => Topic started by: Mark Mc on February 04, 2018, 11:53:16 PM

Title: Haven’t given up yet.
Post by: Mark Mc on February 04, 2018, 11:53:16 PM
Even though I ordered a new Saito FA-40a last week, I still haven’t given up on making my gimme FA-40 work.  I hurt my shoulder last week and it hurts to move it, so I was looking for something to play with while I can’t really work on any projects.  I decided to finally clean up the FA-40 that’s been sitting on a gimme trainer plane for a couple of years and weigh it.

I know I’m on my own setting this up, but I see three ways to run this engine.

1)   Just wire open the throttle, put a layer of RTV around the barrel to prevent any variable air leaks, and adjust the needle very slightly rich.


2)   Wire open the throttle, put a layer of RTV around the barrel to prevent any leaks, and use the slide choke aperture to choke down the inlet in a semblance of Bob Reeves’ nylon choke screw.

(https://s5.postimg.org/ny1hd9slj/test4.jpg) (https://postimages.org/)

(https://s5.postimg.org/gi27rg2bb/test3.jpg) (https://postimages.org/)

(https://s5.postimg.org/izdyyrrdj/test5.jpg) (https://postimages.org/)




3)   Since the intake tube is a press fit into the carb, replace the carb with a delrin block drilled through on one side to fit the intake tube and the other for venturi flow, then cross drill for a fuel spigot on one side and the nylon screw on the other.

(https://s5.postimg.org/vqs55itif/test6.jpg) (https://postimages.org/)

(https://s5.postimg.org/9g4a50thz/test7.jpg) (https://postimages.org/)



When I get this engine cleaned up I’ll put it on a stand and try Method 2 and see if it’ll give a steady 8100 RPM on a couple of props.  It’s a shame I don’t have a plane I can try it on, even with my limited abilities.

So, what do Y’all think my chances are?

Title: Re: Haven’t given up yet.
Post by: Dane Martin on February 05, 2018, 08:19:31 AM
I had that same engine on an RC piper cub. I ended up giving my friend the Cub and he flew it once and gave me the engine back. He put a 72 on it instead. He said the plane wouldn't fly. It didn't have enough power. I laughed and asked him how did I fly it for 10 years without knowing that? Lol.
The plane was a "60 size" piper cub. That little 40 flew the wings off of it for me. The saito 40 will always be high up on my favorites list.
Title: Re: Haven’t given up yet.
Post by: Robert Zambelli on February 05, 2018, 09:06:42 AM
I'm not sure that yours is the 40A.
The 40A is the newer version.
I have one just like yours and it's a great little engine.
I would say it makes the power of an FP 40.
The 40A is lighter and much more powerful.
I'll post some photos as soon as possible.
Bob Z.
Title: Re: Haven’t given up yet.
Post by: Mark Mc on February 05, 2018, 11:08:47 AM
I'm not sure that yours is the 40A.
The 40A is the newer version.
Bob Z.

Bob,

Sorry for the confusion.  The pictured engine is not the 40a.  It's an older FA-40 that weighs a ton.  My scale shows 14.9 ounces.  I should get the 40a today, if the USPS tracking info is correct.  But I still want to make the older 40 work.  BTW, do you know who is selling parts for the older Saitos?  Cleaning up the engine shows I need new boots for the pushrod tubes.  The ones on this engine are cracked and need replacement before I run it.

But, I'd still love to see any photos.

Mark
Title: Re: Haven’t given up yet.
Post by: Robert Zambelli on February 05, 2018, 03:50:15 PM
Hey, Mark.
As far as I know, there are no parts available for the older Saito engines.
BUT, I have some old stuff.
I wil check and see. If I have the boots I'll give them to you.
I had my Saito 40 on a somewhat heavy 600 square inch stunter and it flew beautifully.

Bob Z.

Title: Re: Haven’t given up yet.
Post by: Mark Mc on February 05, 2018, 04:57:06 PM
Hey, Mark.
As far as I know, there are no parts available for the older Saito engines.
BUT, I have some old stuff.
I wil check and see. If I have the boots I'll give them to you.
I had my Saito 40 on a somewhat heavy 600 square inch stunter and it flew beautifully.

Bob Z.

Thank you very much!

It's good to hear that it flew well on a heavy 600 incher.  Looking through all the posts on Stunthanger, there are a lot saying that the engine is weak for its size.  I think one post said, "The power of a Fox 35 at twice the weight".  I'm glad to know it'll pull it's own weight through the air.  I want to use the older engine to get used to four stroke operation before I risk the new shiny one.  Of course, any time I take a plane up, the engine is at great risk...

Mark
Title: Re: Haven’t given up yet.
Post by: Robert Zambelli on February 07, 2018, 03:11:05 PM
Bob,

Sorry for the confusion.  The pictured engine is not the 40a.  It's an older FA-40 that weighs a ton.  My scale shows 14.9 ounces.  I should get the 40a today, if the USPS tracking info is correct.  But I still want to make the older 40 work.  BTW, do you know who is selling parts for the older Saitos?  Cleaning up the engine shows I need new boots for the pushrod tubes.  The ones on this engine are cracked and need replacement before I run it.

But, I'd still love to see any photos.

Mark

I have the boots you need.
Title: Re: Haven’t given up yet.
Post by: Mark Mc on February 26, 2018, 08:39:08 PM
I wanted to say a big “Thank You” to Bob for sending me a pair of boots for the pushrod tubes on my FA-40.  I got them a few days ago, and I promptly put them on.  But I hurt my arm right after that and even typing hurts, so I’ve been remiss on posting this.  I didn’t want Bob to think they didn’t get here, or that I’d not appreciated the generous gift.  They look great on the engine.  Now if my arm would just heal and the rain would stop, I can put this on the test stand and get it dialed in.


(https://s5.postimg.org/yd6tulwcn/DSCN5911.jpg) (https://postimages.org/)

Thanks again, Bob!
Mark