Fuel System Question - Saito Twin
 

I have a Saito FA-90TS Flat Twin. I am running it on the "bench" to break it in. The fuel pressure to the tank is provided by the crankcase. When I turn it over, the carb. fills up with fuel and fuel sprays everywhere! I have already opened a vent hole in the cap of the fuel tank, but I can't leave it there once I install it in the plane. The photos in the owner's manual are hard to see, nor does it depict the 90TS specifically (bummer!), but it seems to say something about a pressure control valve. Is this my answer? Will I need to constantly adjust this valve when I fly? Where can I get a simple, in-line, fuel valve like this? Are there other solutions?

Thank you in advance for your help everyone!

ckelloggjr

RE: Fuel System Question - Saito Twin
 

Hello; Your problem is using the oil drain port to pressurise your fuel tank. Try setting it all up with no pressure at all and see what you get. I have a 100 twin that pressureises the tank with a fitting on one of the exhaust pipes. Due to the timing of the engines and the pressure pulse occuring once per rotation, one cylinder won't be getting the same pressure as the other. I had to use two tanks to get my 100 to carberate properly.

RE: Fuel System Question - Saito Twin
 

A single Cline regulater mounted off of the twin carbs of the 1.00 with a T fitting and one tank and a single clunk will produce the sweetest running twin you have ever seen. I know, I flew one for several years. I had people come up to me @ flyins and ask what kind of engine was in there, and what brand on board glow did I use. They would allmost do back flips, when my responce was a Saito 1.00 Twin with no onboard Glow.

RE: Fuel System Question - Saito Twin
 

A 90 TS has a single carb. It is the alternate firing version with the double throw crank and a single cam shaft. Both pistons go to top dead center at the same time.

The engine should run very well with the pressure from one exhaust pipe.
http://image2-6.rcuniverse.com/e1/ga...4/lg-87948.jpg
http://image2-6.rcuniverse.com/e1/ga...4/lg-87947.jpg

RE: Fuel System Question - Saito Twin
 

W8ye,
I AM WELL AWARE OF THE .90TS. IT IS JUST THE BIGGER BROTHER TO THE .60 TWIN. I WAS JUST STATING WHAT IT TOOK TO MAKE A REAL RELIABLE 1.00 TWIN (SINGLE THROW CRANK WITH TWO CARBS).:D I DID NOT NEED TWO TANKS OR TWO CLUNKS.:D THE CLINE MADE ALL THE DIFFERENCE IN THE WORLD SINCE THE CARBS ARE MOUNTED SO HIGH THAT YOU WOULD NEVER GET DECENT FUEL DRAW IN MOST APPLICATIONS.:D

RE: Fuel System Question - Saito Twin
 

Now Dave, everybody knows that you need to do it like this so you can use more stuff. More stuff = more fun.;)

RE: Fuel System Question - Saito Twin
 

Hobbsy,
I was able to get by with one Cline since the Carbs are much closer than your 1.30, or is that the 1.82.? There was like a 1" pice on each carb to the Aluminum Tee and then just enough to connect the cline to the tee. It worked awesome. This was my first of many Clines, and was installed in 1995, in a Clipped Wing GP .60 size Cub. It turned if I remember correctly approx. 9,700-9800 with a APC 14-6 on WC 20/20. Like I said before, people at flyins could not believe how well I had the engine running and with no onboard glow. I used the little stacks from the Saito .40's and .50's of yester year, only one one pipe had a pressure fitting right up by the nut. It had such a nice idle. I sold the engine to someone in VA in 2000 on EBAY.:D:D

RE: Fuel System Question - Saito Twin
 

I have 1 carb. 1 main high speed needle valve. The book says that the nipple located on the carb inlet goes to the exhaust to drain excess fuel away from the air inlet. I've tried, the hose to the exhaust does nothing to bring fuel up to the carb. If the pressure nipple on the case is not for the fuel pump, what does hook up there? What is a "cline"? I am lost. Could someone send a photo of the 90TS all plumbed or tell me where everything goes?

RE: Fuel System Question - Saito Twin
 

A"cline" refers to the Cline regulator. It's the little square thing near each of the carbs on Hobbsy's twin. It also uses a 1 way valve in the pressure line to the fuel tank to pressurize the tank. It's easy to hook up, and comes with instructions.