OS 46-FX & PT-40?

I'm brand new at all this stuff, so go easy on me...
I'm building a Great Planes PT-40 ARF
with an OS .46 FX
engine .
The engine doesn't seem to fit in the cowling, though. The needle valve
coming off the backplate makes it too wide. My question is, what should
I do about this? Get a new engine? Put on a new carburator? Modify the
What do other people do when their engine doesn't fit?
Thanks in advance.
Reply to
Joel Konkle-Parker
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Modify the airplane by cutting a hole for the needle valve to fit through.
Joel K> I'm brand new at all this stuff, so go easy on me...
Reply to
Vance Howard
Trim away the wood where the needle valve is hitting.
Reply to
Don Hatten
You will probably have to notch the cheek piece to let the needle valve exit. Normal modification for any plane with a cowling, cheek pieces, etc. You can also insert a piece of pushrod into the end of the needle valve knob and drill a hole thru the cheek for it to exit the engine compartment. Easy to insert the pushrod extension thru the already drilled hole. I am assembling a Global Fokker D-VII biplane and I had to cut holes for the top of head to clear, a hole to allow access to the glow plug, a hole for the mixture adjustment extension, etc.
Reply to
Fubar of The HillPeople
On 10/11/2003 8:08 PM Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:
Trim the "cheek" piece so the needle valve clears it. There is a small set screw in the side of the needle valve. If you make an "L" from a piece of 1/16" wire and secure it with the set screw you will have all the extension you need to clear the fuselage side (If you need it). BTW, the area you cut away, put some clear dope, or thin CA on the area to fuel proof it.
Reply to
Ted Campanelli
The other people who responded are correct - cut a notch in the side wall of the fuselage to clear the needle valve. I took a couple of pictures of my PT-40 with an OS 40 SF (about 10 years old, back when the needle valves were at the front of the engine) to show the notch I had to cut for its clearance. Do something similar on yours, and remember to fuel-proof the wood somehow after you cut the notch (I think I epoxied it and then covered it with Monokote).
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Reply to
Joe Bill

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