The International Cessna^® 170 Association

I am trying to find an oversized stud to replace a stripped stud on my accessory case at the tach cable mount Part Number 401800. I am looking for either 401800P007 or 401800P012.

I am really having a problem locating a source for the part, does anyone have any ideas of companies that would stock the part.

Thank You

Have you tried Crankcase Services or Aircraft Specialties in Tulsa. They are my go to sources for engine parts.

Clean up the hole and heli-coil it.

No luck with Crankcase Services or Aircraft Specialties. I called Continental's parts department (probably where I should have stared) and they did not have any but the salesman dieted me to a company called Fresno Air Parts Co 559-237-4863. He asked for the actual dimension of the stud and had studs in stock that would fit the bill.

Just passing on the info incase someone else needs another option when looking for engine studs.

T. C. Downey wrote:Clean up the hole and heli-coil it.

That sounds like a simpler/better option than over sizing and re-tapping the hole.

bagarre wrote:

T. C. Downey wrote:Clean up the hole and heli-coil it.

That sounds like a simpler/better option than over sizing and re-tapping the hole.

"Oversizing" a stud does not mean going to the next standard size, for example from a 1/4 to a 5/16 stud. It means using a stud that is only a few thousandths larger than standard so it will fit tighter in worn threads in the casting. MUCH easier than installing a helicoil, IF you can find the oversize stud. I seem to remember numbers like 0.005, 0.007, etc. oversize studs being listed in the engine parts manual.

Learn something new every day.

Lycoming oversize studs start at 0.003" and go to 0.010" I believe. Anytime we remove a stud at the factory we go oversized for replacement.

cessna170bdriver wrote:

bagarre wrote:

T. C. Downey wrote:Clean up the hole and heli-coil it.

That sounds like a simpler/better option than over sizing and re-tapping the hole.

"Oversizing" a stud does not mean going to the next standard size, for example from a 1/4 to a 5/16 stud. It means using a stud that is only a few thousandths larger than standard so it will fit tighter in worn threads in the casting. MUCH easier than installing a helicoil, IF you can find the oversize stud. I seem to remember numbers like 0.005, 0.007, etc. oversize studs being listed in the engine parts manual.

That usually doesn't work when the stud was pulled out by over torquing, and the threads are pulled out.