prop bolts

simatos · Post by **simatos** » Sat May 21, 2005 4:54 am

I mentioned this question under the spinner topic but mabe I will get more bites if I start a new thread

I have the 6 bolt crank O-300-d engine. Prop bolts are I believe AN8-44. Today I called Spruce and they told me they are less than $2.00 each. This is either too good to be true or these aren't the right bolts. Any ideas Thanks G

mit · Post by **mit** » Sat May 21, 2005 6:01 am

try AN8-H44A, they may cost a little more

DuaneShockey · Post by **DuaneShockey** » Sun May 22, 2005 12:29 am

I got a set for my O-300A for $100 a year ago. I think Cessna wanted about $40 each. I can get the part number off the package at a later date if you wish. I don't know if As and Bs are the same bolt. Duane Shockey

blueldr · Post by **blueldr** » Sun May 22, 2005 2:25 am

simatos wrote:I mentioned this question under the spinner topic but mabe I will get more bites if I start a new thread

I have the 6 bolt crank O-300-d engine. Prop bolts are I believe AN8-44. Today I called Spruce and they told me they are less than $2.00 each. This is either too good to be true or these aren't the right bolts. Any ideas Thanks G

Cessna 170 IPC, page 79, Bolt, propeller attach, AN6-H-45

simatos · Post by **simatos** » Sun May 22, 2005 6:41 pm

Guys As You will see I am just learning about this AN bolt sizing system. The early O-300 engines with 8 bolt crank have smaller diameter bolts than the later 6 bolt crank. I am looking for info for the 6 bolt crank. The AN 8 i think is a 1/2 inch diameter and the dash 44 is 4 1/2 in length. This I believe focuses in on the size I am looking for but I guess the H 44 A designates the special prop bolt Ithink which is also drilled as described by MIT above. Does this sound right??Again I really appreciate all your recomendations and help. Soon I expect I will actually fly the thing and i will really be driving you all nuts with more off the wall questions, Thanks again G

mit · Post by **mit** » Sun May 22, 2005 7:48 pm

simatos wrote:Guys As You will see I am just learning about this AN bolt sizing system. The early O-300 engines with 8 bolt crank have smaller diameter bolts than the later 6 bolt crank. I am looking for info for the 6 bolt crank. The AN 8 i think is a 1/2 inch diameter and the dash 44 is 4 1/2 in length. This I believe focuses in on the size I am looking for but I guess the H 44 A designates the special prop bolt Ithink which is also drilled as described by MIT above. Does this sound right??Again I really appreciate all your recomendations and help. Soon I expect I will actually fly the thing and i will really be driving you all nuts with more off the wall questions, Thanks again G

You got it. The H means it is a drilled head, the A means it does NOT have a drilled shank. First # is the Diameter in 16ths, second # is length.
Then there is a C for corrosion resisting, which shows up as a - on the head of the bolt.

The AN76 is the old prop bolt that had a hole drilled through every flat on the head. Spruce still lists them in the catalog with a note about substitutions.

The C145 uses AN6. Your O-300D I can't remember what the DIA is, but it is 6 instead of 8 bolts.

Just make sure you get drill headed bolts and they will probably cost a little more than the ones you talked about in your orgianal post.

Post by **GAHorn** » Sun May 22, 2005 11:14 pm

Yep. AN bolt nomenclature is in 1/16's of an inch. The way I remember it is: AN6H44A (equals 6/16ths, i.e., 3/8's inch diameter, Head drilled for safety-wire, 44/16ths inch-long shank (does not include head), shank is Absent hole for safety-wire )

blueldr · Post by **blueldr** » Mon May 23, 2005 4:38 am

gahorn wrote:Yep. AN bolt nomenclature is in 1/16's of an inch. The way I remember it is: AN6H44A (equals 6/16ths, i.e., 3/8's inch diameter, Head drilled for safety-wire, 44/16ths inch-long shank (does not include head), shank is Absent hole for safety-wire )

All right George, now let's do that shank length code one more time!

Shank length is in eighths of an inch and each inch is coded as ten.
Therefore 44 length is four and four eighths inches or 4 1/2".
See! You knew that , didn't you.

Do I get to count that as a "Gotcha"?

Post by **GAHorn** » Mon May 23, 2005 5:26 am

That was just a test to see if you noticed!!!

Boy, ...that WAS an amatuerish error! Doh!

(I was trying to get the idea of "A" standing for Absent....and got my head up my ....er... well....anyway..THANKS for correcting me. You have won ALL YOUR MEALS PAID by me at the next Reklaw Fly-in, Dick!

Yep, an AN6-4 bolt has a shank one-half inch long, and an AN6-7 bolt has a shank seven/eigths inch long...and an AN6-10 bolt has a shank 1 inch long. (So the -44A bolt is 4.5 inches long and with undrilled shank.)
And by the way, an AN6H bolt has the head drilled only once...while the AN76 series is drilled thru every flat on the head to afford greater flexibility when safetying the bolt.

cessna170bdriver · Post by **cessna170bdriver** » Mon May 23, 2005 10:08 pm

Blueldr wrote:

Shank length is in eighths of an inch and each inch is coded as ten.
Therefore 44 length is four and four eighths inches or 4 1/2".

More on this at http://www.eaa1000.av.org/refernce/an3_18a.htm ( an article from EAA Chapter 1000 about why you can't buy -18 bolts.

Miles

Tom Downey · Post by **Tom Downey** » Tue May 24, 2005 4:24 am

Thyere is an easy explanation at

http://www.aircraftspruce.com/catalog/h ... nbolts.php

ron74887 · Post by **ron74887** » Fri May 27, 2005 12:44 am

g simantos here is the answer to the prop bolts the O300d engine needs 6- A2513-16, 12-AN960-816L washers and 6- MS 20365-820C nuts. there are no wiring holes in the bolts or nuts and are not required. You must torque them to 55-65 ft/lbs. You also have two dowel pins in the prop flange. As far as the pitch, the prop is a 1C172EM series 51 climb, 53 std and, 55 cruise however static rpm at max throttle setting must not be over 2350 nor under 2230. Dia can be not be under 74.5" nor over 76". as per the type certificate 3A12 and specified in the STC . These are Cessna parts nos. any question about the STC call me R. Massicot 337-332-4597 good luck

richard d miller · Post by **richard d miller** » Thu Aug 11, 2016 4:40 am

Yes just figured this out on my newly purchased AC today. Have a 53' 170 six bolt 3/4 inch and the proper bolts are AN 365 1216s fm Aircraft Spruce. About 3.50 ea. Know because had to purchase the nuts as you can't reuse after taking prop off. They're teflon locking and not a good idea to reuse. Now I'm just looking for a torque spec?

richard d miller · Post by **richard d miller** » Thu Aug 11, 2016 4:43 am

Correction fm that last post. I meant the AN 365 1216 number is for the nuts for the 3/4 inch bolts. Sorry......those you have to get new after removal and reinstall..........

Post by **GAHorn** » Thu Aug 11, 2016 9:01 pm

Per Chap 14, (Propeller) 100 series Service Manual:

Torque SIX bolts to 55-65 ft lbs.

Torque EIGHT bolts to 250 IN lbs. (21 ft lbs)

The International Cessna 170 Association

prop bolts

prop bolts

Re: prop bolts

Re: prop bolts

Re: prop bolts

Re: prop bolts