Treat oil leaks seriously

How about coolant?
The rotax LSA I fly often has no coolant in the reservoir during pre-flight, with no trace of it anywhere upon visible inspection. Meaning that it went somewhere during the last flight. Nobody else at the school seems too concerned - it's just filled up again and we're ready to go.
That ain't right.

Look for coolant coming out of the weep hole on the bottom of the rear accessory case - that's where a bad water pump seal will drip.
1716408172444.png
 
Last edited:
This is good advice, and as someone who has always done my own (car) oil changes until my wife's newest car, I think that is among the easiest tasks to undertake, but people usually pay for the convenience. My question was more to the point of: if you aren't mechanically inclined and you encounter this problem, so you take it to a "professional" and he (or in this case all three) tells you that it isn't a big deal and just take care of it at annual, what additional steps could or should he take?

I totally agree with the sentiments expressed, so this is not for argument's sake, just for those who may visit this thread later, or for those of us in discussion to better arm ourselves for the future. He didn't blindly trust the first A&P he sought out a second and third opinion. What additional steps do you feel like he could take to better safeguard himself and his passengers?
One suggestion is to take a short flight over the field after any maintenance. Make sure everything sounds and feels right. Then take a look around the plane for oil seepage, including under the fuselage. I'm very comfortable checking my A&P's work, but I won't go on a long XC right after a maintenance event. This is also a good practice if you end up AOG and have a repair away from home. Spend 30 minutes in the pattern and make sure everything is working ok before continuing on your journey.
 
Just to add on post-maintenance ops. Technically a mechanic only approves an aircraft for return to service. Its a pilot that actually returns the aircraft to service after maintenance by accepting the aircraft for flight or flying the aircraft. However, in some cases there is a requirement per Part 91 to perform an ops check flight after maintenance and log the flight in the record. Regardless, I'm a big fan of a post mx flight for most maintenance just to verify nothing else was disturbed during the performance of the maintenance to include popping the cowling and giving it a quick look over. Some of my customers didn't like it but its the cheapest insurance out there from my point of view.
 
Always change your own oil. When you do, give your engine and FWF a washdown with mineral spirits until it is spotless. Eyeball all fasteners in the engine compartment. Verify all drilled bolts are wired and all castle nuts are cottered. Put torque stripe on other nuts and bolts and check those. Visually inspect hoses, cables, wires, belts, and connectors. Clean the cowl thoroughly too, inside and out.

While you are at it, pull your wheel pants off, clean the gunk off your hubs and brakes, check your tire pressure, and wash your wheel pants.

Put everything back together, run it for 5 or 10 minutes, do a visual check for obvious leaks, then take it for a quick flight to get it up to normal operating temp. After the flight, use a flashlight to closely inspect the engine compartment for any evidence of leaks.

None of this takes an A&P. Once you get practiced and know your plane well, the full process will take an hour or two. You will be rewarded with much greater confidence in your aircraft, and a higher likelihood of catching a leak before it becomes an emergency.
 
Always change your own oil. When you do, give your engine and FWF a washdown with mineral spirits until it is spotless. Eyeball all fasteners in the engine compartment. Verify all drilled bolts are wired and all castle nuts are cottered. Put torque stripe on other nuts and bolts and check those. Visually inspect hoses, cables, wires, belts, and connectors. Clean the cowl thoroughly too, inside and out.

While you are at it, pull your wheel pants off, clean the gunk off your hubs and brakes, check your tire pressure, and wash your wheel pants.
Just don't spray solvents into the alternator's cooling openings or near the typical vacuum pump that has an open drive, which is most of them. Tempest has a sealed drive with a special gasket that has an oil drain port at the bottom so that solvents are discouraged from getting in there.

Solvent softens the insulating varnish on the alternator's rotor and stator coils, making short circuiting possible. It can get as the field brushes, which are graphite blocks, and dissolve them a bit so they gum up the slip rings and reduce the current flow to the field, which limits the alternator's output.

The vacuum pump has a graphite rotor and graphite vanes. Any oil or solvent getting into it (there is no positive seal against that) will also gum things up and cause rotor failure.

Solvent into magneto vents is another thing to avoid.

1716488894177.png


A non-pressurized mag also has no gasket between the body housings, and solvent under pressure could get in there too.
 
Not as bad as radials, but having a bunch of hours now behind the ole Conti O-300... if there's no oil under it, there's no oil in it...
After our last two overhauls (one caused by me impinging on the runway) ours leaked nary a drop. Burned it quite well, however.
 
Back
Top