what to do with engine data plate when converting engine

I have an O-320-E2A core for my -9A project. It is a 150 HP engine with 7:1 compression ratio.

My plan is to change the cylinder assemblies to 8.5:1 compression ratios during the overhaul. After looking at the Lycoming Parts Catalogs, I think this changes the engine configuration from O-320-E2A to O-320-D2A.

In this case, how does one change the data plate? The current one is pretty old / faded. I imagine at a minimum I'd want to change the engine model number and HP rating.

In a related question (maybe for Mel?) - the engine model number defines the accessories too (magetos, fuel system, etc.). If I want to change those as well what do I do with the data plate in that case?

I might even choose to put an experimental magneto or fuel injection system on. In that case there is no Lycoming part number that is correct. What have others done?

Disclaimer: I am not an A&P

Anyway, I will venture an opinion (subject to correction by those more knowledgeable than me) - once you change ANYTHING on a certified engine, absent an appropriate log entry by someone legally entitled to do so, it immediately becomes experimental, so what else you do to it is academic. It is still experimental. My engine started life as an O-360-A1G6D, but now has a vertical induction sump and carb - functionally an A1A, but not quite, as I have not changed the accessory case. Even if I had , it still would not legally be an A1A.

Like Sam says, this engine is an experimental engine. Whatever you do to the data plate is up to you.
You might keep in mind that the engine is also no longer a "Lycoming". You do not have authority to change a Lycoming data plate.
At most, I would simply add "-X" to the data plate or remove it. Most people just leave it as is.
It's kinda like changing empty weight. You change it in the weight and balance documents, but you don't change the data plate.

BTW, you don't need to change cylinders to go to 8.5:1 compression. Only the pistons and wrist pins need changing.

I went through the trouble of having a new data plate engraved for the IO-540 I went through myself and made the appropriate log book entry indicating that the engine was now in the experimental catagory. I affixed the original Lycoming data plate under the new data plate so it would not get lost. My DAR stated that I could have just left the original in place and that the log book entry was sufficient.

If there is room, X out the current designation with metal letter dies and restamp it as:

O-320-D2A Conversion - Experimental

Mel said:

the engine is also no longer a "Lycoming". You do not have authority to change a Lycoming data plate.
At most, I would simply add "-X" to the data plate or remove it. Most people just leave it as is.

Click to expand...

Thanks Mel - that is my concern. The engine will no longer be a Lycoming O-320-E2A, so I didn't want to leave the data plate as-is. I'm surprised it is OK to leave it.

I like the idea of adding a '-X' or CONVERSION or something.

Thanks to all!

BTW - I noticed I could use the cylinders if they are nitrided (at least per the Lycoming Parts Catalog for the D2A) but I think the ones I have are probably shot and it will be easier to replace them as assemblies.

Changing data plate

It depends on who you are and what you are doing to the engine.

S.I. 1304J and FAR 45.13

""Field facilities may not change data contained on an engine data plate, but may add a suffix, usually C which indicates a change from its original manufacture."" (This includes documenting the changes made in the logbooks etc.)

Technically your engine is still a certified Lycoming until it is hung on an experimental airplane, especially if you are a mechanic and you used certified Lycoming parts during the overhaul.

I was told by Lycoming that if the engine changes kept the engine in the same type certificate the model designation could be changed. In my case the engine has no variants of the horsepower rating I am converting it to, so they said it cannot be changed.

Since you are an A&P and leaving most of the original engine parts together in the overhaul I would not remove or alter the data plate other than to somehow mark it to denote that changes have been made and carefully document them in the engine logbook.

As everyone has said once it is on an experimental aircraft it cannot be placed back on a certified plane. I know of builders who installed a Lycoming engine without the data plate and then got crosswise with FAA inspectors who insisted that the engine was still a Lycoming and had to have been assembled to Lycoming standards.

Dave A.

IowaRV9Dreamer said:

I have an O-320-E2A core for my -9A project. It is a 150 HP engine with 7:1 compression ratio.

My plan is to change the cylinder assemblies to 8.5:1 compression ratios during the overhaul. After looking at the Lycoming Parts Catalogs, I think this changes the engine configuration from O-320-E2A to O-320-D2A.

In this case, how does one change the data plate? The current one is pretty old / faded. I imagine at a minimum I'd want to change the engine model number and HP rating.

In a related question (maybe for Mel?) - the engine model number defines the accessories too (magetos, fuel system, etc.). If I want to change those as well what do I do with the data plate in that case?

I might even choose to put an experimental magneto or fuel injection system on. In that case there is no Lycoming part number that is correct. What have others done?

Click to expand...

There is a little more than changing cylinders assemblies to due a proper conversion. Will your crank pass the 505? I understand its legal but is it safe? You might want to go through the power section to be sure it can handle the extra 10 pony's. I believe these are the small nose bearings as well as the smaller intake tubes, you might need to drill the main jet on the ma-4 to get the mixture right. Time to get the Sky Ranch book out.Your engine is no place to short cut. Fly Safe my Friends!
RHill

Rename it.

We overhauled our 0-360 but aren't A@P's. We flipped the data plate and engraved it "Smith-Morgan O-360. DAR gave thumbs-up.

Best,

rhill said:

There is a little more than changing cylinders assemblies to due a proper conversion. Will your crank pass the 505? I understand its legal but is it safe? You might want to go through the power section to be sure it can handle the extra 10 pony's. I believe these are the small nose bearings as well as the smaller intake tubes, you might need to drill the main jet on the ma-4 to get the mixture right. Time to get the Sky Ranch book out.Your engine is no place to short cut. Fly Safe my Friends!
RHill

Click to expand...

Thanks Rhill - I certainly want to do a proper conversion.

I've already had the crank pass the SB-505 inspection. I exhaustively went though the two parts catalogs and can confirm that the only differences between and O-320-E2A and -D2A are the pistons, rings and cylinders. The pistons are higher compression and the rings/cylinders are nitrided. The entire rest of the engine is identical. There are multiple carb part numbers listed for each engine - and 3 of the 4 are the same.

Engine plate

I rebuilt my IO-360B1E for my 8 and replaced the rear faced sump with a front facing sump. Now its a IO-360B1E-C. Local engine builder (Randy Rubbert) said thats what he does.

engine

Lots of homebuilts with plain steel cylinders and 160 hp pistons. For certified engine nitride or plated cylinders are required.
One interesting fact I ran across recently is that one experimental engine builder is using the thin wall piston pins with high compression pistons.

Changes are good

I agree with Mel. You may wish to not do anything to the data plate, but just gently take it off and save it. If you change anything about the engine that data plate is not valid to that engine any longer. However you may fined that, that data plate is of value down the road. It has been known to happen that a good data plate becomes of interest, from time to time and you may change your mind and go back to the way you found this engine in the first place. Hope this helps Your as always R.E.A. III #80888