Gear Box Repair Notes from My Experience others may differ
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
-
- Posts: 526
- Joined: Thu Dec 02, 2004 1:52 am
Gear Box Repair Notes from My Experience others may differ
Gear box differences between Cessna 170’s, 180’s and 172’s
Essentially the two main landing gear bulkheads and forward door post bulkheads in the case of 172s are the same part number 0513006-9 Fwd and 0513006-103 Aft in all three models of aircraft up through 172 serial numbers 17251822 and P 17257188. And all Cessna 180-185s through 1976 as gleaned from the parts manuals I have on hand. After that the part number changes to 0513374-1 and -5 respectively but it is primarily detail differences in the later part numbers. And could probably be used in rebuilding the gear box for any 170 or early model 180 or 185. The primary differences in the final bulkhead assemblies of a 172 compared to a 170 or 180 is that the 172 forward bulkhead does not have the two steel doublers on the outboard ends (part number 0713495-11) front left and -12 front .right. The 170 and 170 A steel fittings are a different part number in the catalog part number 051495-19 & 20 left and right however they are physically the same when examined in the hand. The -19 is currently not listed as of this date on cessnaparts.com. However the 05114-20 is superseded to 0713495-16. The forward bulkhead also does not have the forward facing extruded angle which goes completely across the forward bulkhead part number 0513006-23. All of these part number 0713495 -*** are currently shown out of stock at Cessna with pricings al from roughly $700 dollars on up to $1700. The other intresting thing about the 172 bulkheads is that in most of the airplanes I have looked in the forward bulkheads are even Piloted for locating the gear box doublers. Of course the 172’s door post bulkheads do not have the Gear box fittings themselves but the main bulkhead parts are the same part number. Also the top cover (floor panel) for the complete gear box assembly 0513006-11 is a thicker plate on the 170 and 180’s than used in the 172. It is also longer fore to aft because it picks up the line of rivets in the forward facing angle of the front bulkhead as installed in the 170-s and 180’s 0513006-11. The lower skin that closes the whole gear box that goes from gear leg to gear leg on the Cessna 170 and 180 series airplanes is thicker than on the Cessna 172 door post bulkhead area. In conclusion I have never used any of the Cessna 172 door post bulkheads to rebuild a Tail dragging 170 or 180. However I did convert a Cessna 172 to a tail dragger and found the components compatible and estimate that the individual parts from a 172 could be used to support rebuilding a 170 or 180 along with finding any of the steel plates that might need to be replaced if damaged. Rivet sizes and spacing may be an issue and would have to addressed. I would recommend a close examination of any components being selected as a donor parts from a Cessna 172 and not purchase them sight unseen.
In the views following the picture with the primed parts is what it looked like before I assembled it back into the fuselage and riveted it back together.It is funny to me that I had actually bought the top gearbox skin from Cessna and I manufactured a new one from 2024 T3 .050 aluminum and riveted it on forgetting that I had purchased the new part which I still have out in the garage.I manufactured the bottom skin of the gear box from 2024 T3 .050 aluminum and ended up making two before I was satisfied. I sent that skin to someone here on the forum years ago to help them performing a Flavel Tail wheel mod to a 172. I had a hard time coming up with two of the steel plates that go onto the outboard end and ended up buying from Cessna the left rear bulkhead plate which turned out to be longer than the original 170A part listed extending further inboard buy about 2 inches as I recall. In any case I just cut off and primered the excess length although it would have fir in without modifcationRS.jpg[/attachment]
An additional Note is that with the beginning of the Cessna 172P the forward door post bulkhead was completely omitted from the construction of 172's Making it nearly impossible to convert them to a Tail Dragger swept tail issues not withstanding.
Essentially the two main landing gear bulkheads and forward door post bulkheads in the case of 172s are the same part number 0513006-9 Fwd and 0513006-103 Aft in all three models of aircraft up through 172 serial numbers 17251822 and P 17257188. And all Cessna 180-185s through 1976 as gleaned from the parts manuals I have on hand. After that the part number changes to 0513374-1 and -5 respectively but it is primarily detail differences in the later part numbers. And could probably be used in rebuilding the gear box for any 170 or early model 180 or 185. The primary differences in the final bulkhead assemblies of a 172 compared to a 170 or 180 is that the 172 forward bulkhead does not have the two steel doublers on the outboard ends (part number 0713495-11) front left and -12 front .right. The 170 and 170 A steel fittings are a different part number in the catalog part number 051495-19 & 20 left and right however they are physically the same when examined in the hand. The -19 is currently not listed as of this date on cessnaparts.com. However the 05114-20 is superseded to 0713495-16. The forward bulkhead also does not have the forward facing extruded angle which goes completely across the forward bulkhead part number 0513006-23. All of these part number 0713495 -*** are currently shown out of stock at Cessna with pricings al from roughly $700 dollars on up to $1700. The other intresting thing about the 172 bulkheads is that in most of the airplanes I have looked in the forward bulkheads are even Piloted for locating the gear box doublers. Of course the 172’s door post bulkheads do not have the Gear box fittings themselves but the main bulkhead parts are the same part number. Also the top cover (floor panel) for the complete gear box assembly 0513006-11 is a thicker plate on the 170 and 180’s than used in the 172. It is also longer fore to aft because it picks up the line of rivets in the forward facing angle of the front bulkhead as installed in the 170-s and 180’s 0513006-11. The lower skin that closes the whole gear box that goes from gear leg to gear leg on the Cessna 170 and 180 series airplanes is thicker than on the Cessna 172 door post bulkhead area. In conclusion I have never used any of the Cessna 172 door post bulkheads to rebuild a Tail dragging 170 or 180. However I did convert a Cessna 172 to a tail dragger and found the components compatible and estimate that the individual parts from a 172 could be used to support rebuilding a 170 or 180 along with finding any of the steel plates that might need to be replaced if damaged. Rivet sizes and spacing may be an issue and would have to addressed. I would recommend a close examination of any components being selected as a donor parts from a Cessna 172 and not purchase them sight unseen.
In the views following the picture with the primed parts is what it looked like before I assembled it back into the fuselage and riveted it back together.It is funny to me that I had actually bought the top gearbox skin from Cessna and I manufactured a new one from 2024 T3 .050 aluminum and riveted it on forgetting that I had purchased the new part which I still have out in the garage.I manufactured the bottom skin of the gear box from 2024 T3 .050 aluminum and ended up making two before I was satisfied. I sent that skin to someone here on the forum years ago to help them performing a Flavel Tail wheel mod to a 172. I had a hard time coming up with two of the steel plates that go onto the outboard end and ended up buying from Cessna the left rear bulkhead plate which turned out to be longer than the original 170A part listed extending further inboard buy about 2 inches as I recall. In any case I just cut off and primered the excess length although it would have fir in without modifcationRS.jpg[/attachment]
An additional Note is that with the beginning of the Cessna 172P the forward door post bulkhead was completely omitted from the construction of 172's Making it nearly impossible to convert them to a Tail Dragger swept tail issues not withstanding.
A&P, IA, New owner C170A N1208D, Have rebuilt some 50 aircraft. So many airplanes, So little time!
-
- Posts: 526
- Joined: Thu Dec 02, 2004 1:52 am
Re: Gear Box Repair Notes from My Experience others may diff
Additional Pictures for referance:
A&P, IA, New owner C170A N1208D, Have rebuilt some 50 aircraft. So many airplanes, So little time!
-
- Posts: 526
- Joined: Thu Dec 02, 2004 1:52 am
Re: Gear Box Repair Notes from My Experience others may diff
One more Picture before I go work on My TCM IO-360 installation:
A&P, IA, New owner C170A N1208D, Have rebuilt some 50 aircraft. So many airplanes, So little time!
Re: Gear Box Repair Notes from My Experience others may diff
Jim, we are so lucky to have members like yourself willing to share their expertise with us. Thank you!
John E. Barrett
aka. Johneb
Sent from my "Cray Super Computer"
aka. Johneb
Sent from my "Cray Super Computer"
- ghostflyer
- Posts: 1395
- Joined: Mon Apr 21, 2008 3:06 am
Re: Gear Box Repair Notes from My Experience others may diff
Well done Metal Master on the clarification on the gearbox, but now I would like to know is the 206 gearbox similar ?
-
- Posts: 526
- Joined: Thu Dec 02, 2004 1:52 am
Re: Gear Box Repair Notes from My Experience others may diff
Not as far as I know. But that would really be stretchering to find suitable parts. The Cessna 210 is a development of the 205 and 206 and the gear box there is considerably wider. My guess is that it is not but I certainly do not know. I have a TU206G that I am responsible for. I will take some rough measurements and take look next week.ghostflyer wrote:Well done Metal Master on the clarification on the gearbox, but now I would like to know is the 206 gearbox similar ?
Update: Looking at the parts catalog for the Cessna 206 the placement of gear fittings is so much further inboard and of different design of the gear fitting I can see no way a Cessna 206 gear bulkhead or gear box could be used to repair a 170 or 180 of any vintage.
Last edited by Metal Master on Mon Dec 07, 2015 7:54 am, edited 1 time in total.
A&P, IA, New owner C170A N1208D, Have rebuilt some 50 aircraft. So many airplanes, So little time!
Re: Gear Box Repair Notes from My Experience others may diff
That is some fine metal work!
Years ago St. Just, a Canadian company, offered a C-180/185 clone kitplane. The Super Cyclone is now offered by Aviatech. I wonder how close their bulkheads are to the original Cessna ones. I see they offer the landing gear box preassembled. Could you call a bulkhead "owner-produced" if you had them stamp one out for you?
Years ago St. Just, a Canadian company, offered a C-180/185 clone kitplane. The Super Cyclone is now offered by Aviatech. I wonder how close their bulkheads are to the original Cessna ones. I see they offer the landing gear box preassembled. Could you call a bulkhead "owner-produced" if you had them stamp one out for you?
Gary
Re: Gear Box Repair Notes from My Experience others may diff
Just awesome Jim, thanks so much
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
1953 C170B S/N 25656
02 K1200RS
Re: Gear Box Repair Notes from My Experience others may diff
You'd have to be involved with the manufacturing process in some way. Provide them the material, verify the quality...n2582d wrote:That is some fine metal work!
Years ago St. Just, a Canadian company, offered a C-180/185 clone kitplane. The Super Cyclone is now offered by Aviatech. I wonder how close their bulkheads are to the original Cessna ones. I see they offer the landing gear box preassembled. Could you call a bulkhead "owner-produced" if you had them stamp one out for you?
You'd also have to verify it was an identical part and have an A&P willing to install the part.
Re: Gear Box Repair Notes from My Experience others may diff
I've been replacing gearbox parts due to elongated rivet holes, extra access holes, etc. and adding the PPonk beef up kit. While working there I was looking at the lower rivet holes on the outboard gearbox fittings. On mine it looks like less than 2D edge distance. I'm hoping this is the way it comes from the factory. My second issue is with the angles which attach the outboard castings to the bottom skin, p/n 0713495-5 (fig. 21-50) on the left and the same p/n on the right but which, according to the revision sheet, has been revised to 0742115-25 (fig.21-56). On mine the rivet patterns are different between the two. Do one of these angles need to be replaced? If so, which one is incorrect? PPonk's replacement for the outboard bracket shows a double row of rivet holes.
Gary
Re: Gear Box Repair Notes from My Experience others may diff
Steve at PPonk was able to answer my question. The 180 and 185 require the use of the double row of rivets. The 170 attach angle only requires a single row as I have on the left side. This was my first time talking with Steve and Norma. Great folks, extremely helpful.
Gary