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What Is An "Engine"?

Vans101

Well Known Member
With respect to logging maintenance in the engine logbook, what components and accessories are considered part of the engine as opposed to part of the airframe.

Specifically, if you install a new electric fuel pump, since that device is bolted to the airframe and not connected to the engine I presume that this is more accurately an airframe component?

Same thing with a remote mounted oil cooler. It is not really a component of the engine so I presume that if the oil cooler was replaced that would be an airframe log entry and not an engine logbook entry since the engine itself was not touched during the R&R. So what about if I were to replace an engine oil cooler hose, yes I had to touch the engine to perform this maintenance and the action needs to be logged however where does one (me) log this work?

How about an alternator belt? The propeller needs to be R&R'd to replace the belt, and the belt is attached to the engine... so do I need to record in the propeller log that the prop was R&R'd an then also in the engine that the belt was R&R'd?

Engine cooling baffles?

Vacuum pump?

Engine mount rubber isolators?

Exhaust pipe? Exhaust pipe cabin heater muff?

I guess I never thought about tis before until I just R&R'd the electric fuel pump.

THANKS for your advice!!!
 
If you would remove it in an engine swap, it's part of the engine. :D

Personally I would log anything firewall-forward that the engine needs to run, as part of the engine, because if something breaks (= engine not working) then you'll look at the engine records. For stuff like exhaust pipe, mount isolators, if it's mainly attached to the engine then I'd log with the engine. Only if it's permanently attached to the airframe would I log it with that. Just my 2¢
 
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On my certified airplane, since I'm an airframe mechanic but don't have the powerplant rating, I wondered the same thing. What I finally decided was that if something is in the airframe parts manual, it's airframe. If it's in the engine parts manual, it's powerplant. I mentioned this to a FSDO inspector once and he accepted it but of course that's not an official FAA guideline.

Since a Lycoming parts manual is readily available, it's an easy metric to follow.

Dave
 
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I follow this philosophy. If I was going to sell the engine to someone, what information would they need? That is the info that I put in the engine log. Electric fuel pumps, oil coolers, etc, and anything not directly bolted to the engine, I put on the airframe log.

My 2 cents.
 
There's no requirement to keep logbooks, only "records" So you can do whatever you want. From a practical standpoint consider what history you'd want to see if you bought a used engine or prop and put the entry there. Sometimes I make entries in multiple logs.
 
sometimes I log things in both books. For example, When I installed electronic ignition I put it in both since it required changes to the engine and airframe electrical system.
 
What is an engine? .....it's a very expensive agricultural piece of equipment that still is being made out of solid gold:D
 
In the world of certified aircraft, A&P's and IA's usually separate records as follows.

The engine record records anything that is related to the core engine that would be required to make it run.

This would be the engine it self, the ign. system (mags, harness, etc.) and fuel delivery (carb., fuel injection system, etc.)

Everything else (starter, alternator, exhaust system) would be considered an accessory and related to the airframe that the engine is installed on (so maint. record entries related to those things would go in the airframe record).

I.E., not all airframes require a starter. Or an alternator. Though all probably need an exhaust, it is still specific to the airframe that the engine is installed on so would not have entries regarding it, in the engine record because a given engine could be installed on a number of different airframes during its life time.
 
What is an engine? .....it's a very expensive agricultural piece of equipment that still is being made out of solid gold:D

I was going to say it's an amalgamation of parts operating around an oil leak... or is that a helicopter?
 
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