O-300-A with 6 bolt crank

[Bruce Fenstermacher]

It is still an A as it's data plate will attest unless the procedures have been followed to change it to another model.

[marathonrunner]

Teledyne Continental Motors M65-14 details instructions for stamping a data plate when making a model change. Basically you stamp a "C" for Change after your moeld number then like from an "A" to a "D" it would read 0-300ACD indicating the change/

SIL 00-9A tells you how to obtain a new data plate if you want to go that route and it costs 100.00 and you need a letter from the FAA.

X-09-06 is the currently active listing for their Service documents, bulletins, lettere, directives, etc.

[Bruce Fenstermacher]

Neat, I didn't know that. I thought putting in the 6 bolt crank required the data plate change to another model, but if it can be used in the -A without changing it, then that's relieves my worries of finding a good 8 bolt when the time comes to rebuild my -A. Sorry to drift off topic!!

Oh you should still be worried. How are you going to find a 6 bolt prop approved for the 170? This prop problem is exactly what lead to Ron Massicot getting our engine STC. In Ron's case he was using a D model which the FAA inspector thought was fine and had no problem using in place of the C-145. But the inspector told Ron he would never get a propellor approve to fit the 0300 six bolt crank. So while we refer to our STC as an engine STC it really is a propellor STC which also makes clear what engines can be installed.

Back to your question. Just installing a 6 bolt crank does not change the engine model. There are plenty of examples of 0-300 A models with later six bolt cranks that are still an 0-300A. In fact the 6 bolt crank is considered the superseded part for the 8 bolt version. We can only assume those aircraft are legal because the owner dotted the I and crossed the T with for the crank change and for the prop and likely spinner change required in some form of approval. Your easiest option might be to actually change the model of the A to a C through the approved method marathonrunner pointed out and then use our Association STC to install the engine, prop and spinner.

This works the other way as well. Less likely but has been done at least once is an 0300C,D or E had a early 8 bolt crank installed allowing the use of original prop and spinner. There is an STC for doing the crank change though an engine model change could have been done through the same engine model change process. The use of this STC has been granted to all TIC170A members free of charge and we believe it to be true and accurate, however the letter of authorization has poor provenance. And then of course you'd have to have approval to install this modified 0-300C,D or E in a 170 and our STC may not help the way it is currently written because it calls for the use of 6 bolt props and spinners.

(FYI, I have written a revision to the Association's STC instructions which is under review by other Association members before making application to the FAA for the revision. The rewrite if approve as I wrote it will address and allow all combinations of C-145 or 0-300 regardless of crank style and all accessories including props and spinner combinations already approved by TCDS or our current STC. This will of course take time to get done and there are no guarantees)

[blueldr]

And then there are the engines that have an IO-360 crank installed. ????

[Bruce Fenstermacher]

And then there are the engines that have an IO-360 crank installed. ????

That would be the 6 bolt replacement crank wouldn't it?

[bagarre]

Does the O-300 six bolt crank have the same part number as the IO-360 crank?
If not, maybe someone needs to write an STC for it.

[Bruce Fenstermacher]

The 0-300 C,D,E crank part number 628124 is superseded by part 653382 available for $ 5,885.56 (EA) plus core.

IO360 cranks part number 639200 and 639786 supersede to 653138 and 653139. The new cranks may all be the same as has been reported but they have different part numbers.

[hilltop170]

When you order a factory new crank for your O-300-D, the factory sends you an IO-360 crank, no STC or 337 required and its legal.

[Bruce Fenstermacher]

Richard, would you be able to confirm what part number crank they sent you? Because as you can see from my research the new 0-300-D crank is not a IO-360 crank by part number.

[hilltop170]

Yes, Bruce, I'll check the logbook when I return to Texas Feb 10.

[GAHorn]

This is likely a "can of worms" but I believe that a -A engine with a 6-bolt cranks is no longer a -A...but is a -C engine and should have it's datatag restruct "ACC" per the TCM bulletin already mentioned. (By specification a -A has an 8-bolt crank, and if a 6-bolt is installed it no longer meets it's TC.) Of course, this requires a prop change and those matters both require a new basis of approval for intallation, hence the need for the TIC170A STC.

[simon.fisher.2]

Hello - I just joined and was wondering if there was an update on the STC for the 0-300 6 bolt crank in the A&B model.

This is the scenario - I just overhauled my O-300B and get a call from the mechanic as he was working on the paperwork. Essentially he is telling me that the crank we installed is technically not approved. Sooo I need to find an STC.

Can someone provide some light on this issue for me? Also if the association offers an STC how do I purchase it?

Thanks,

Simon

[Bruce Fenstermacher]

Simon,

If I understand correctly you installed a 6 bolt crank in a 0-300B. And then you want to install that and a different prop and spinner on your A or B model. You are actually making two modifications. One to the engine and then to the airframe.

In effect you are changing that engine to a 0-300C. There is no STC to do this but it can be done by following the procedures outlined by Continental to change the engine to a C.

Then you can buy the Associations STC to install that 0-300C and the different prop and the spinner onto your airplane.

BTW joining this forum is not the same as joining the TIC170A in which there are dues involved. Get your mechanic to agree he can make that engine a C model then join the Association and buy the STC to hang the engine on your airframe. Cost of STC is $75 to members.

[ron74887]

Bruce/Simon, what Bruce just said is not exactly right. The 0-300-B had the prop adjustment deal on it and the C does not. I'd have to go thru notes but if you lock the adjustment out you'd be legal. The E engine has controls (if I remember right) for a variable pitch control not like the B engine but thru the hub assembly. I also think you can remove/blank the adjustment lever off??? Bruce correct me if I am wrong here. The C-145-2H and the B are the only 2 with that prop deal (for the 2 position prop). So you would not be converting it to a C unless you either locked it out or blanked it off- Right Bruce??? Ron

[c170b53]

I think Ron the lever is lock wired to the fine pitch position. That's what mine had and I think the crank would have had the oil passage and plug.