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Lycoming Service Instruction O-320 150hp to 160hp conversion

jrussl

jrussl

BENEFACTOR
Madison, WI
Does anyone have a copy (and be willing to share it) of the Lycoming Service Instruction for converting a O-320 from 150hp A2B to 160hp B2B?

I am rebuilding my engine and, even though I already had the high compression pistons prior to rebuild (installed with no paperwork), I am now installing factory new 160hp pistons and cylinders. I need the service instruction to get all my paperwork in order.

Thanks in advance

Jeff
 
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SI 1304J for the engine, you can probably find it on line or I can probably dig it up and scan. Svenns Aviation for the install stc, support the locals. I wrote a cub clues article a long time ago about 320 conversions, not sure if that is available anywhere, not sure if I still have a copy, but it would be good info.
 
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Interestingly enough, I just talked to an employee of LyCon about this conversion. I was considering buying a used O320-A2B for a core to send them in order to build me an 8.5 engine. He told me in order to be certified it had to start life as a wide deck. He then offered to sell me a core.
 
I used Lycon’s O-320 wide deck 150 to 160 hp conversion STC. Sent Lycon my narrow deck-27 case, upgraded to the -39 case. They did the 505B inspection on the crank and ported the cylinders for me... LyCon also sent me a new data plate to be placed behind the original Lycoming data plate.


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This subject has been brought up before: https://www.supercub.org/forum/showthread.php?21387-Converting-a-150hp-to-160hp-or-is-it-10-1/page2
Look at Darrel Starr's post #47.
Lycoming built 160 hp 0-320s with a narrow deck. Lycon likely has their own STC which spells out wide deck only. IMO based upon a letter I've seen from a well known NY engine rebuilder, the alteration is a minor. Meaning, just comply with the parts which are described in the parts manual.

You will need an STC to use the engine in your Cub. This is an airframe installation STC, not an STC to alter the engine.
 
Seems like I've seen narrow deck 320's converted to 160hp,
as I recall they need the banana plates installed.
 
bfabb8cd9527b57c71325049dfdb95d7.jpg

Was an O-320 A2A... Lycon STC conversion to O-320 B2B using their wide deck STC...Lycon sent me the deviation document for the narrow deck conversion.

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Thanks everyone for all the great info.

I ordered the Svenns Aviation STC for the 160hp as my current STC only covers the 150hp.

Boz, I went though my incomplete collection of Cub Clues and did not find the article. If you think you have it, I would sure appreciate a copy.

And thanks for the link to the service instruction. My engine is a wide deck. Question.....other than the parts manual, is there anything other instruction for converting the A2B to a B2B?

I will work with my A&P to deal with the actual engine conversion as minor alteration.

This all is just to get my paperwork straightened out as my engine has already spent the last 20 years as 160hp.

And now that the engine will be "officially" a B2B, I need to get the Peterson auto gas STC as the EAA STC will no longer apply. Sigh!

Thanks again, everyone.

Jeff
 
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The engine type certificate E-274 which lists the differences between the a and b should also be referenced. The TC, SI, current parts and overhaul manual are all approved data for your mechanic to use. I'll dig around tonight for that old clues, to nice today to stay inside.
 
SuperCub MD said:
The engine type certificate E-274 which lists the differences between the a and b should also be referenced. The TC, SI, current parts and overhaul manual are all approved data for your mechanic to use. I'll dig around tonight for that old clues, to nice today to stay inside.
Click to expand...

Minor correction here, manufacturers parts catalogs and overhaul manuals are not approved data, only accepted data. Remember, the overhaul of a non supercharged, non geared engine is only a minor repair. Changing models would be a major alteration, but your approved data is the SL and the TC.


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CBE47098-8A34-40F1-9F49-93B47FEF0274.jpg
For what it's worth, my engine was field approved to 160 in 1998 when it was overhauled last time. A2A wide deck.
 

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Yeah, I know what that SL says, but when you look at the manuals there is no “FAA approved”, and there is no provision in CAR 13, or 14CFR 33 for approving service documents. Likewise in the Type Certification guide, they explicitly state that only the Airworthiness Limitations section is approved data. That said, many Service Bulletins, & Service Letters are Approved Data and state that. For it to actually be Approved Data, it has to state that in the document (typically on each page that is approved). Unfortunately FAA and the predecessor CAA weren’t very consistent here. In any case, it is FAA policy that if an action is a minor repair (overhaul of an engine), it is contrary to the regulations to approve data for that operation. As a DER, I can’t approve data for minor repairs or minor alterations.


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PA-22/20-160 said:
I just happen to have a case I’m getting ready to paint and both A2B and B2B narrow deck studs here.
View attachment 53817View attachment 53818View attachment 53819View attachment 53820
Click to expand...
What are you using to install the studs? I had a stud leak after topping it and talking to Ken at LyCon found out he pulls all the studs even though the crankcase shops don't and he puts them in with Loctite but Loctite reacts from two ferrous metals and aluminum won't create that reaction. His case guy hooked me up with the correct Loctite and primer to get the seal and with the proper working time which is an issue with the other primer. Ken said he started doing all his cases this way because he got tired of dealing with it under warranty. Teledyne Continental Motors calls it out in a service bulletin on chemicals, coatings etc. Will look at the bottles when I get to the hangar.

Oh yea, the Six just fit in his hangar. He is gonna tear it down and build a bigger hangar. ;)
 
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