Oversized Studs

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N2523D
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Oversized Studs

Post by N2523D »

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
Richard Thomsen
1952 Cessna 170B - N2523D
El Monte Airport (KEMT)
Lopez
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Re: Oversized Studs

Post by Lopez »

Have you tried Crankcase Services or Aircraft Specialties in Tulsa. They are my go to sources for engine parts.
T. C. Downey
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Re: Oversized Studs

Post by T. C. Downey »

Clean up the hole and heli-coil it.
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N2523D
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Re: Oversized Studs

Post by N2523D »

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.
Richard Thomsen
1952 Cessna 170B - N2523D
El Monte Airport (KEMT)
bagarre
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Re: Oversized Studs

Post by bagarre »

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.
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cessna170bdriver
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Re: Oversized Studs

Post by cessna170bdriver »

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.
Miles

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bagarre
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Re: Oversized Studs

Post by bagarre »

Learn something new every day.
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rupertjl
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Re: Oversized Studs

Post by rupertjl »

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.
1950 170A: N9191A s/n 19366
T. C. Downey
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Re: Oversized Studs

Post by T. C. Downey »

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.
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