swisseagle

Well Known Member
Hello

I got my engine TMX-IO-320 with a ?plain? dipstick, no marks on it. So now the question how to evaluate the oil-levels correctly?
Until now, I was measuring in cm/mm and had a table aside. Now an oil-change is needed, so it's the right moment to do it correctly.

I have no problems to make the marks ... but other questions to do it right:

1. Do I screw in the dip stick to get the measurement correct or do I just push it against the thread?

2. Theoretically: If the engine is ?empty? (dry, no oil in an empty filter) fill up and mark accordingly. The quantity in the oil pan is the value shown on the dipstick.
During usage, the level shown on the dipstick, will always be lower than the total amount of oil in the ?complete engine?.
Or more practically:
Drain the used oil, take out, clean and reinstall the screen, fill with oil and mark accordingly. Then change the oil filter. The quantity in the oil pan and system
is the value shown on the dipstick. This due to the fact that the system was still filled with oil.

So, how should I proceed?

Thanks alot!

Dominik
 
Start with aircraft in normal parked attitude on level surface.

1. Drain all oil out and clean change filters so almost no oil is in the engine. All plugs, filters are installed, torqued, and safetied.
2. Add one unit of oil. (In the US we use quarts.)
3. Screw in oil dip stick.
4. Remove dip stick and check level.
5. Determine if you want a mark on the dip stick at this level. Add mark if you want an indication at this level.

My O-320 has marks every 2-quarts. Not sure what the lowest number is as I never let it get below 4. Lycoming says max is 8 and I have no marks above 8.

When I change oil and spin on filter, I add 7-quarts of clean oil. The dip stick show oil 1/2 way between the 6 and 8 marks. After running engine and letting it sit over night, I see between 6.25 and 6.375 quarts on the stick.
 
With a new oil filter, I would add 4 quarts, run the motor for a couple of minutes, check for leaks and then let it set for a few hours. unscrew the dip stick and place it on a piece of paper to help see the oil level if it is not obvious. Mark it 4 quarts.

After that, add 1 quart, let it set, mark the dip stick and repeat the process for each quart.
I only add 7 quarts during an oil change.
 
With a new oil filter, I would add 4 quarts, run the motor for a couple of minutes, check for leaks and then let it set for a few hours. unscrew the dip stick and place it on a piece of paper to help see the oil level if it is not obvious. Mark it 4 quarts.

After that, add 1 quart, let it set, mark the dip stick and repeat the process for each quart.
I only add 7 quarts during an oil change.

I disagree. Lycoming specs the sump level, not the total oil in the system. Simple way would be to drain sump (after running), then fill 4, 6, 8 to establish the marks, then change the filter if required.
 
To each his own

Each aircraft may have a different sump and fill stick set-up. As stated above the way it has been done in the field, is to drain what you can out of the sump and with the aircraft on flat ground, level, just fill the sump with four quarts and make your 4 quart mark on the stick at that level. The 6 quart mark and the 8 quart mark, if you have an 8 quart sump. The system and oil passages will always hold a little left over oil, so what you really what to meter is what is in the sump "oil pan" at any time you dip it. Just what we have done and the last guy and the one before him. Yours R.E.A. III #80888