green river rc

My Feedback: (2)

I am ready to start my old OS 40-FS and realized there is no place for the pressure line. My engine has a straight pipe with no muffler there for no fitting to attach the pressure line to. I checked the OS website but the engine in the manual is a generic picture with a muffer. Any ideas?

Thanks for the help!
GR

jeffie8696

Some early 4S engines were not equipped with pressurized systems. Try adjusting it normally with the tank simply vented . Remember rich = good, lean = bad.

jaka

Hi!
You don't need any pressure for that engine!
Best prop is a 11x6.
Had one 30 years ago, and have another one new in box laying.

NM2K

My Feedback: (14)

I have two of the OS FS-40 engines that are NIB. Both are modern renditions. I also have two OS FS-30 and two Magnum FS-30 engines, also all NIB. All of these engines were intended to power a B-36 model bomber. None have been ran, fueled, propped or even mounted. The best laid plans of mice and men...


Ed Cregger

jeffie8696

squeak

green river rc

My Feedback: (2)

Well I mounted the engine on my 20 year old kit built Sig Kadet Sr and it flew pretty good! I was surprised that it ran as well as it did with no pressure, I did have to blow into the pressure line to feed fuel into the carb (and my mouth) and it starts first flip. I have an 11x6 wood prop and it pulls the Senior around better than the OS 40 FP I was flying it with, also the bolt pattern was the same as the 40 FP so the swap was easy just had to run the throttle push rod to the other side. The 20 year old Monokote covering job is getting very brittle, the new engine has sparked new intrest in my old plane, I may recover it with Koverall and dope and maybe this classic will fly another 20 years. BTW this is the plane I tought myself to fly with and was the second plane I ever built, not many folks can say that I think. I'll go out today and get a picture.

jeffie8696

Ifind it interesting how a 4S engine will pull through a maneuver using engine torque compared to the rpm required for a 2S engine.

jaka

Hi!
???

mike109

G'day

Glad to hear you got the old FS going again and even more to hear you have it in a Kadet Senior. I used to fly a Kadet Senior with an OS FS 40. It was no powerhouse but it was great fun.

I used to use muffler pressure on it but they really don't need it as you have discovered. I found that the muffler off an Enya 46 would fit on to the end of the exhaust pipe and this made for a very quiet engine.

Like you, I used to blow on the end of the muffler pipe to prime my 40 too. And like you, I found it would start easily with one flip of the prop.

I still have the engine. Most recently it was flying a very old and tired Sig Kadet LT-25. I ended up giving the model to a friend and building a new LT-25 but I put a shiny new Enya 36 four stroke in it. The old 40 is still waiting for a new assignment. I am thinking of building a Seniorita and perhaps it could go there?

Cheers

Mike in Oz

green river rc

My Feedback: (2)

Not a lot of difference between how an OS 40 FS and an OS 40 FP flies the Kadet Sr, not much that I can tell anyways.

mike109

G'day

I have had a string of Kadet Seniors and I have always preferred to power them with four strokes. They sound quieter (though they measure about the same), they use less fuel, they are happy to plod around all day on half power and they pull the large dirty airframe that is a Kadet better. A Kadet Senior is never going to be a race horse and the ability of the four stroke to swing a larger prop at lower revs is a benefit.

Recently I flew one which a friend had put an MDS 46 two stroke into. I though it would be fast but it was just the same as all the others I have flown. I did have one with an ASP 91 four stroke in it. Now that was quick but I think that had I left it there, I would have pulled the wings off.

Cheers

Mike in Oz