The International Cessna^® 170 Association

I've got an O-300-B that I want to convert to a O-300-A. Can anybody with a O-300 parts manual tell me if the part number for the crankshaft of the A and B models are the same or different? I'm hoping the only thing I have to change is to remove the prop control device on the left forward side of the engine.

The crank is the same.

Why do you want to remove the control device?

The O-300-B is not an approved engine for the C-170.

See FAR 43-A

I quote

(2) Powerplant major alterations. The following alterations of a powerplant when not listed in the engine specifications issued by the FAA, are powerplant major alterations.

(i) Conversion of an aircraft engine from one approved model to another, involving any changes in compression ratio, propeller reduction gear, impeller gear ratios or the substitution of major engine parts which requires extensive rework and testing of the engine.

(ii) Changes to the engine by replacing aircraft engine structural parts with parts not supplied by the original manufacturer or parts not specifically approved by the Administrator.

(iii) Installation of an accessory which is not approved for the engine.

(iv) Removal of accessories that are listed as required equipment on the aircraft or engine specification.

(v) Installation of structural parts other than the type of parts approved for the installation.

(vi) Conversions of any sort for the purpose of using fuel of a rating or grade other than that listed in the engine specifications.

N9149A wrote:The crank is the same.

Why do you want to remove the control device?

I must correct myself. Knew I should have looked in the book.

The C-145-2H and the 0300-B use the same crank.

The C-145-2 and the 0-300-A use the same crank.

The 0-300-C and 0-300-D use the same crank.

The C-145-2H is an approved engine and is the same as the 0-300-B according to the type certificate for the engine, the overhaul manual and the parts manual. The C-145-2H was like the other models was just renamed to the 0-300 convention by Continental.

While you are correct in that the 0-300-B is not in the aircraft type certificate directly it is by association. Some would think that's enough but to be sure I wouldn't think you'd have to much trouble getting an approval for the B model as is. give your FSDO a call and present all the data. That being the three manuals I just mentioned.

Trying to convert the B model engine to an A model will be just as much if not more of a can of worms paperwork wise.

I'm don't remember if Ron Massicot's engine STC sold through the TIC170A for a very reasonable price, covers the B model. It does cover installation of the C and D models.

Tom,
Thanks for that quote from the FAA. The way I read it then converting from a O-300-B to a O-300-A would be a minor alteration. Here is what Teledyne Continental has to say about doing a model change: http://www.tcmlink.com/pdf2/M75-6R1.pdf

Bruce,
As much as I'd like to see the "-B" as an approved engine the TCDS says the C-145-2 is the approved engine and to see item #112. Item #112 lists the O-300-A and"(same limits as for C-145-2 or -2H)". I don't think this parenthesis is approving the -2H for mounting on the C-170. Please prove me wrong!

Gary, Look at the first page of the type cert. data sheet for the 170 A and B. It lists the C-145-2 and C-145-2H as approved engines. (But not for the straight 170.)
The use of M75-6R to convert one engine model to another still requires a Form 337 (but does not require FAA approval of Block 3, Field Approval.)
While the C-145-2H is stated by the Type cert to be similar to the C145-2 except for crancase and cranshaft provisions for hydraulically controlled propeller.... and the same statement is made as regards the O-300-B as it relates to the O-300-A,... the TCDS does not specifically claim the O-300-B is similar to the C-145-2H. A really picky FSDO might argue the O-300-B is not eligible for the 170 unless you can get the similarity statement directly from TCM. (He'd really be the difficult type tho', in my opinion.)
Hope this helps.

George your are correct in that the best the manuals say is the engines are similier but I challenge anyone to find a single part that is different between the C-145-2H and the 0-300-B.

While I'd rather not have to convince a FSDO guy this is one argument I'd feel real confident I'd win. The difficulty would be making the FSDO guy think it was his idea.

I think that if I had an O-300-B that I wanted to make legal for a C-170... I'd also try to find a controllable prop to go along with it!

E-253 Teledyne Continental Motors

CONTINENTAL

Revision 18

C145-2, -2H, -2HP

O-300-A, -B, -C, -D, -E

March 1, 1974


Sorry about the size of the post.

TYPE CERTIFICATE DATA SHEET NO. E-253

Engines of models described herein, conforming with this data sheet (which is part of Type Certificate No. E-253) and other approved data on file with the Federal Aviation Agency meet the minimum standards for use in certificated aircraft in accordance with pertinent aircraft data sheets and applicable portions of the Civil Air Regulations, provided they are installed, operated, and maintained as prescribed by the approved manufacturer's manuals and other approved instructions.

TYPE CERTIFICATE HOLDER:

Teledyne Continental Motors

P.O. Box 90

Mobile, Alabama 36601


MODEL

C145-2, -2H, -2HP

O-300-A, -B, -C, -D, -E


TYPE

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 6HOA


RATING

ICAO or ARDC, standard atmosphere

Max. continuous hp., rpm, full throttle at sea level pressure altitude

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 145-2700

Takeoff hp., 5 min. rpm, full throttle at sea level pressure altitude

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 145-2700


FUEL

(Min. grade aviation gasoline)

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 80/87


LUBRICATING OIL

Oil inlet temperature

Below 120°F

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- Oil Grade SAE 20

Over 120°F

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- Oil Grade SAE 40


BORE AND STROKE, IN.

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 4.0625 x 3.875


DISPLACEMENT, CU. IN.

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 301


COMPRESSION RATIO

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 7.0:1


WEIGHT (DRY), LB.

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 268


C.G. LOCATION

(With accessories where eligible)

Fwd. of mounting lug rear face, in.

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 8.1

Below crankshaft, in.

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 1.6


PROPELLER SHAFT, SAE NO.

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- See NOTE 7


CARBURETION

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- Marvel-Schebler MA-3SPA P/N 530490


IGNITION, DUAL MAGNETOS

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- Bendix-Scintilla SF6LN-12 or S6LN-21, or J.I. Case Model 67 or Slick Electro 664; or 1 ea. Bendix-Scintilla S6LN-200 or -204


TIMING, °BTC

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- Right 26, Left 28


SPARK PLUGS

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- See NOTE 8


OIL SUMP CAPACITY, QT.

C145-2, -2H, -2HP, O-300-A, -B, -C, -D, -E -- 8; 7.46 usable at 5° nose-up and 5.6 usable at 5° nose-down; 7.76 usable at 10° nose-up and 3.77 usable at 10° nose-down attitudes


NOTES

C145-2, -2H, -2HP -- 1, 2, 3, 4, 5, 7, 8

O-300-A, -B, -C, -D, -E -- 1, 2, 3, 5, 6, 7, 8


CERTIFICATION BASIS

CAR 13

Type Certificate No. 253 issued for C145-2 December 5, 1947; C145-2H added April 1, 1949; C145-2HP added January 27, 1953; O-300-A added May 12, 1954; O-300-B added September 27, 1955; O-300-C added February 24, 1959; O-300-D added June 1, 1960; O-300-E added April 3, 1963.


PRODUCTION BASIS

Production Certificate Nos. 7 and 508.

Note 1. Maximum permissible cylinder head, barrel and oil inlet temperatures, 525°F, 290°F, and 225°F, respectively.

Maximum oil inlet temperature limit is 240°F when using Spec MHS-24 oil SAE No. 50 above 40°F ambient and SAE No. 30 or 10W30 below 40°F. ambient.

NOTE 2. Pressure limits for normal operation:

Fuel at carburetor inlet: For pump system 1-1/2 to 6 p s.i.g.

For gravity system: Minimum 11 in. fuel head differential between carburetor fuel inlet fitting and float bowl chamber, maximum 6 p.s i.g.

Oil -- 30 to 40 p.s.i.g.

NOTE 3. The following accessory drive or mounting provisions are available

Direc- Speed
tion Ratio Maximum
Type of to Max. Torque Overhang
of Rota- Crank- (in.-lb.) Moment
Accessory Drive tion* shaft Cont. Static (in-lb)
Generator Automotive CC 2.035:1 60 600 100
**Starter Automotive C 35.77:1
***Starter Automatic C 24.727:1
engagement
****Vacuum AND 20,000 CC 1.545:1 100 800 25
pump
Fuel pump Automotive 0.500:1
diaphragm
*****Governor AND 20,010 1:1 29 825 50
* C - Clockwise viewing drive pad, CC - Counter Clockwise

** Delco-Remy gear reduction drive and starter eligible on all models except O-300-D and -E .

*** Delco-Remy starter (CMC P/N 627842) with Continental adapter P/N 628158 eligible on Model O-300-D and -E only.

**** Vacuum pump drive available on Model O-300-D and -E only.

***** Governor drive available on Model O-300-E only.

NOTE 4. Model designation suffix "H" on model C145-2 denotes the incorporation of crankcase and crankshaft provisions for use of a hydraulically controllable propeller from the engine oil pressure. Model designation suffix "P" denotes engine eligible for pusher installation as permitted by a special crankcase and front main bearing.

NOTE 5. C145 series engines equipped with dampered crankshafts are identified by suffix letter "D" following the engine serial number which denotes one each 5th and 6th order dampers. 0-300 series engines are also equipped with crankshaft incorporating one each 5th and 6th order dampers.

NOTE 6. O-300-A is similar to C145-2 except parts material and ignition component substitutions. O-300-B is similar to O-300-A except incorporates crankcase and crankshaft provisions for use of a hydraulically controllable propeller from the engine oil pressure. O-300-C is identical to O-300-A except for propeller flange provisions as indicated. O-300-D is similar to O-300-C except for provisions for Continental right angle automatic engagement starter drive which incorporates a vacuum pump drive. O-300-E is similar to O-300-D except for incorporation of governor drive pad and crankshaft provisions to supply governor oil to propeller.

NOTE 7. Propeller shaft

C145-2, -2H, -2HP; O-300-A, -B: SAE-AS127 No. 3 flange

O-300-C, -D, -E: ARP502 Type I flange 4-7/8 in. o d by .31 in. thick with six 1/2 in. bolt holes in 4 in. diameter circle. O-300-E has provisions for transfer of governor oil to propeller.

NOTE 8. The following spark plugs are approved for these models:

AC - HSR33IR, SR831R, SR83P, HSR83P, A88, S88, S88D, HS88, SR88, HSR88, SR88D

Auto Lite - BR4, BR4S, BR4SB, H15, SH15, SH15R, SH20A, SH150, SH200A

BG - RB485S, RB919SR5, RB955S, 706, 706S

Champion - C26S, RC26S, C27, C27S, REM38E, REM38P, REM38W, RHM38P, RHM38W RED39N, REM39N, RHD39N, RHM39N, REM40E, RHM40E, D41N, ED41N, EM41N, M41N, M42E, EM42E

Red Seal - SA190, SE190, SJ190, SE230, SJ230

If it were my aircraft/engine I'd upgrade to the XP mod.

George and Bruce,
Thanks for proving me wrong! I was looking at the C-170 rather than the C-170B data. I must have some Scandanavian blood!

As far as the prop goes, the Swift guys don't have much good to say about the Aerormatic except that it looks good on a wall. http://www.napanet.net/~arbeau/swift/props4.htm
I see that a McCauley two-position controllable prop is also an option. Anybody know anything about these? At 60 lbs. it seems pretty heavy.

Tom,
The IO-360-K, KB, and C are approved for the XP-mods conversion. The KB has the 2000 hr TBO vs. 1500 for the other models. The C has 210 hp. vs. 195 for the others. Which is the preferred version? It's interesting that the TSIO-360-A, AB, D, and DB are 43 lbs. lighter than the former models according to the Teledyne Continental website. http://www.tcmlink.com/producthighlights/ENGTBL.PDF How is that possible? In any case, I'll have to run this O-300 to TBO, (and the kids through college) before I can financially consider the IO-360. Maybe by then the deltahawk diesel will be STC'ed for the C-170! http://www.deltahawkengines.com/econom00.shtml

n2582d wrote:George and Bruce,
...
As far as the prop goes, the Swift guys don't have much good to say about the Aeromatic except that it looks good on a wall. http://www.napanet.net/~arbeau/swift/props4.htm
I see that a McCauley two-position controllable prop is also an option. Anybody know anything about these? At 60 lbs. it seems pretty heavy.

...

Gary

My only exposure to the Aeromatic prop is a friend who is flying one on his Ranger powered Great Lakes. He flies aerobatics for fun and seems to like the prop. I'd be tempted to try one if one in airworthy condition came my way AND I had a -2H or -B model engine making it legal. This is not to say I'd invest much money it it though.

As for the McCauley 2 position prop it's hard to say how many are around and or how hard it would be to find one. I can tell you this about how rare they may be. It wasn't till Dave and Ruth Bengtson showed up at Petit Jean fly-in two years ago with one installed that many long time 170 people actually saw one.

Dave had no idea how rare his installation might be and really hadn't made a study whether it was worth it. He was very surprised to have so many people gawking at his prop figuring it was common 170 equipment.

Dave told me that he wasn't even sure his prop was working right or adjusted correctly because there wasn't much difference between high and low setting.

As for the "B" 0-300 engine. my memory could use some refreshing, the part that N2582D wants to remove and replace with a standard continental cover plate only acts as a lever? I seem to remember that the small crank is attached to a spool that ports oil pressure. Does the pilot position that spool or does engine oil pressure position it ?

In the case of the 170 and the McCauley 2 postion prop the pilot moves a selector in the cabin which moves the lever via a cable. The lever turns a spindle which directs oil pressure which changes the prop.

Here are pictures of the McCauley prop and the control knob in the 170.