Cessna heated pitot attach screws

[jimbo]

I bought a used Cessna 150/152 heated pitot and I'll be danged that I can't find screws that fit into the pitot housing for attaching to the mast. Tried 6-32, diameter looks right but the thread doesn't fit. Metric doesn't fit. My guess is that it maybe a 6-40 but I don't know where to find those to even check. 6-40 is a rare animal.

Anyone else run into this ? I suppose I could drill out the 4 holes and re-tap for a bigger screw.

Jim
RV9A

[terrye]

Don't drill them out! The screws are as you suspected #6-40 which is the fine thread series (UNF) where the #6-32 is the coarse thread series (UNC).

Cessna's parts book lists these as AN507-640R4 which is a 100 degree flat head machine screw, #6-40 thread, 1/4" long. Also available as a stainless steel AN507C-640R4.

Try Aircraft Spruce, Wicks, or a Cessna dealer

[Rustic29]

Jim,
I needed four screws and bought the mn qty....probably 100.
I'll mail you a couple.
What's the address?
Dave

[Rustic29]

Jim,
I needed four screws and bought the mIn qty....probably 100.
I'll mail you a couple.
What's the address?
Dave

[jimbo]

Thanks for all who replied. Another fellow bldr graciously offered me some extras he had so I am taking him up on it.

Jim

[GAHco]

All AN spec pitot tubes use 6-40 screws.

Stock Items, Cad Plated Steel or Stainless.
Packaged in 50's

Tech page

http://www.gen-aircraft-hardware.com...tot_Screws.pdf

To purchase

http://www.gen-aircraft-hardware.com...188~188&id=188