IO-540 Engine question

DKirkpatrick

Pre-takeoff checklist
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DKirkpatrick
Anyone know if an IO-540C4B5 could be converted to fit into a Piper Comanche that has an IO-540-R1A5 in it...?? Intel and help would be MUCH appreciated.

thanks



Dan
 
my understanding is that if the engine in question is not included as part of the engine choices available on the type certificate data sheet (TCDS) then youre you're looking at an stc. if no stc has been done for it, then its on you to submit for one, and the cost is generally prohibitive. what im 99 sure of is that such an engine swap cant be done via simpleton field approval authority.
 
I didn’t interpret the question as that he wanted to put the C4B5 on the plane as is but he wanted to turn the C4B5 into an R1A5 to use on it.

Converting an engine from one model to another might be able to be done. I’d suggest calling an engine shop and asking the question and see what their response is.
 
The TCDS is available. Compare the differences between the two versions:

http://wiki.velocityoba.com/images/d/d0/IO-540_Type_certificate1E4.pdf

My read says you'd need the stiffer crank, the different balance weights, piston oil squirters, and a turbo. Maybe other accesories too - I took a superficial look.

So, bottom line, I don't think it would be a "bolt on the turbo, call it an R1A5, and go" conversion.
 
Converting one engine to another also requires an STC for the engine modification, and an STC to put that converted engine on the plane.

We have an O-540-B2C5 235HP, upgraded to 250HP by STC with different pistons and I think exhaust valves. It is now an O-540-B2C5-A1D5. The A1D5 engine is the 250HP version of the O540 that is in the Comanche, same case, so it fits.

Then you need the STC that approves the install of the modified engine on the Pawnee.

But you can’t go buy a straight O540-A1D5 and put it on the Pawnee.
I did find one STC that allowed that, but it was serial number specific for one installation only with no engineering data to back it up.
 
Converting one engine to another also requires an STC for the engine modification, and an STC to put that converted engine on the plane.

You sure about that? If the engine is modified (i.e. parts swapped) to convert to the correct engine model, do you need an STC (since it already meets the TC)? I would think a logbook entry would suffice as long as the engine, after conversion, is on the TC for the airframe.
 
You sure about that? If the engine is modified (i.e. parts swapped) to convert to the correct engine model, do you need an STC (since it already meets the TC)? I would think a logbook entry would suffice as long as the engine, after conversion, is on the TC for the airframe.
You are changing the data plate to reflect the engine change. If you check the data plate and serial number on the engine and it does not match the original engine as it left the factory without a paperwork trail. Not good.

The engine as modified was not on the original TCDS for the aircraft.
 
You sure about that? If the engine is modified (i.e. parts swapped) to convert to the correct engine model, do you need an STC (since it already meets the TC)? I would think a logbook entry would suffice as long as the engine, after conversion, is on the TC for the airframe.
I'll second this....a TC already exists for the "new" configuration....so no additional engine STC is needed. IMHO. Now, the data plate and log books need to be addressed.

No one can change a data plate....but the logs do need to reflect the current approved configuration.

The installation is another issue....and that may require an STC.
 
Only the TC or PC holder can change the core model from one to another. For everyone else it would be a major alteration.
 
I've done it. Took an O-320 out of a 172 to install into a Cherokee. Changed the rear case and gearing for the mechanical fuel pump, maybe some other small changes. Dug into the IPC and TCDS to determine the exact differences between the engines and part numbers required. Went through all applicable Lycoming SB's and SI's. Sent an email to Transport Canada outlining the project and requesting approval to change the data plate. Ordered parts, did the work, sent in a major repair/alteration form.

Very labour intensive at best.
 
You sure about that? If the engine is modified (i.e. parts swapped) to convert to the correct engine model, do you need an STC (since it already meets the TC)? I would think a logbook entry would suffice as long as the engine, after conversion, is on the TC for the airframe.
You are starting with an engine that is not correct for the airframe according to the type certificate. So the original post wants to modify it to match an engine that meets the TC. It’s still a modified engine, STC needed to change the data plate, and STC needed to put the modified engine in the airframe.
 
I've done it. Took an O-320 out of a 172 to install into a Cherokee. Changed the rear case and gearing for the mechanical fuel pump, maybe some other small changes. Dug into the IPC and TCDS to determine the exact differences between the engines and part numbers required. Went through all applicable Lycoming SB's and SI's. Sent an email to Transport Canada outlining the project and requesting approval to change the data plate. Ordered parts, did the work, sent in a major repair/alteration form.

Very labour intensive at best.
Ahhh, but you have the paperwork, and permission from a governing agency to update the dataplate. That is a lot more than just a logbook entry as suggested by the original post.
 
Whew!
Just looking for a replacement for this original in the Comanche. Problem with finding another engine is that I'm told it's a popular engine for all the homebuilders...
Thanks for the help though
dan
 
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