C

Camillo

Well Known Member
Hallo. It seems that my first fly will happen soon: I hope to start my engine in a week or so.

I am a bit confused about preoiling procedure.

According to SI 1241C, I have to fill the oil tank or sump (point #1). Point #3 states that for wet sump engines, the oil cooler should be filled, too (this implies disconnecting the oil inlet line). And then. Remove 1 spark per cylinder. Turn engine with starter until oil is visible on the disconnected oil line. Reconnect. Turn engine again until 20 lbs. of pressure is obtained. Reinstall plugs. Start the engine.

Questions is: do I also have to follow point #3 and fill the oil cooler tank or the tank will be filled from the engine itself, while cranking? (Some folks here on the VAF fill the tank). Is the O-320 D1A (bought new from Van's 2 years ago) a dry or wet sump engine? (sorry for the stupid question...)

Any other suggestion for my first engine start?

Thanks.
 
It is a wet sump engine. If you remove the spark plugs and crank the engine with the starter at 30 second intervals with 2 minutes rest in-between, until you get an oil pressure needle wiggle, you should be OK as far as pre-oiling goes for the first start up, in my opinion.
Good Luck,
Mahlon

"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."
 
Preoil

This is a must do, and it really isn't that hard. The duty cycle on most starters is 30 sec. on, 2 min off, 30 sec. on, half hour off. That is with the spark plugs installed. It is possible to work them longer under lighter load, just make sure it doesn't get to hot. Blow it cool if you like, just remember some of the innerds get heat soaked and sooner or later it will need time to dissipate that heat. I have had some engines fail to prime (oil pump). I put 5 to 10 psi in the crankcase through the breather tube to force the oil into the pump while cranking. This happens about half the time. I run the starter twice before I do that. Sometimes the line going to the oil pressure gauge needs to be loosened at the gauge to get a good read on the pressure.
 
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Hand prop

Rather than cycling the starter and running the engine through compression cycles without oil, I removed the top spark plug from each cylinder and then rotated the engine by hand using the prop. I constructed the engine myself and made sure everything was well greased at assembly, but it had been about a year and a half until first start. You'd be surprised at how quickly you can actually spin the engine by hand with no compression :). I took it easy at first and then after a number of revolutions got the prop spinning and the oil pressure up to several psi just by hand propping. This gave me the assurance that it was well oiled. No need to make a fancy pre-oil system.
 
On my Cessna 180 I installed a pre-oiler from this company:
http://www.oilamatic.com/

I use it on every start-up and shut-down.

You can sure tell the difference when moving a prop with the unit on!

The company is local and provided impressive service when I bought it. The unit now has over 500 hours and about sixteen years (I didn't fly much for a decade) and is like new.

Except as a happy customer, I have no other connection to the company.
 
mahlon_r said:
It is a wet sump engine. If you remove the spark plugs and crank the engine with the starter at 30 second intervals with 2 minutes rest in-between, until you get an oil pressure needle wiggle, you should be OK as far as pre-oiling goes for the first start up, in my opinion.
Good Luck,
Mahlon

"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."
Click to expand...


Why pull the plugs? Less work for the starter?
 
trib said:
Rather than cycling the starter and running the engine through compression cycles without oil, I removed the top spark plug from each cylinder and then rotated the engine by hand using the prop. I constructed the engine myself and made sure everything was well greased at assembly, but it had been about a year and a half until first start. You'd be surprised at how quickly you can actually spin the engine by hand with no compression :). I took it easy at first and then after a number of revolutions got the prop spinning and the oil pressure up to several psi just by hand propping. This gave me the assurance that it was well oiled. No need to make a fancy pre-oil system.
Click to expand...

Same here, only I pulled the bottom plugs so any oil left in the cylinders will drain out. That and I did spin it a few times with the starter as well.

Make sure to wipe up any oil that drains out of the plug holes because it will blow back and cover the firewall.

Also, make sure you have the spinner in place. If you have the backing plate on with the tabs behind the prop and no spinner when the engine starts means those tabs will probably be thrown off by the centrifugal force.
 
David Paule said:
On my Cessna 180 I installed a pre-oiler from this company:
http://www.oilamatic.com/

I use it on every start-up and shut-down.

You can sure tell the difference when moving a prop with the unit on!

The company is local and provided impressive service when I bought it. The unit now has over 500 hours and about sixteen years (I didn't fly much for a decade) and is like new.

Except as a happy customer, I have no other connection to the company.
Click to expand...


Pure genius. Why has no one ever thought of this before?
 
Pre-oilers have been around for some time. Unfortunately they miss one important function for a Lycoming. They don't pre-oil the cam lobes (unless you have the "Ney" nozzles installed). And this is the main wear point, as the cam lobes are only oiled by "splash" while the engine is running.
 
Assembly lube

Bill Dicus said:
Mel: Does cranking (fast with plugs our) provide splash oiling to the cam lobes?Bill
Click to expand...

It has been a while since I have built up an engine but I believe you will find that all critical surfaces, journals, etc... are lubed with "assembly lube", basically a relatively thin grease.
Perhaps the engine guru's here can debunk this or add to it....
 
JonJay said:
It has been a while since I have built up an engine but I believe you will find that all critical surfaces, journals, etc... are lubed with "assembly lube", basically a relatively thin grease.
Perhaps the engine guru's here can debunk this or add to it....
Click to expand...


From the automotive engines I've built, always used something to pre-lube. i.e. giving a new cam a good coat of oil prior to install.
 
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