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ao.frog

Well Known Member
Hi.

I'm preparing for first start and have just pre-oiled the oil pressure sensor.
It now shows 13-17 PSI when cranking the engine without the spark plugs.
(Is this a ok oil press by the way?)

My question is: schould I preoil the C/S prop too? For example by loosening the nut on the C/S oil line by the forward end of the baffles?

Thanks
 
Alf,
FWIW, I usually check my plugs when I change the oil (bottom plugs 25 hours, and top and bottom plugs 50 hours) and clean time if necessary. I have been cranking the engine over without the plugs to get the oil pressure up, so it won't have the empty filter and cooler on first start. I usually see around 35 to 40# of pressure when cranking it over. It spins pretty good. I have an 0-360 c/s prop.

Oil pressure in cruise is around 75#.

I really don't know that it means anything or not. The engine guru's will have to let us know, but I would watch the oil pressure very closely on first start.
 
I didn't do mine.

ao.frog said:
Hi.

I'm preparing for first start and have just pre-oiled the oil pressure sensor.
It now shows 13-17 PSI when cranking the engine without the spark plugs.
(Is this a ok oil press by the way?)

My question is: schould I preoil the C/S prop too? For example by loosening the nut on the C/S oil line by the forward end of the baffles?

Thanks
Click to expand...

I pre-oiled my engine with a oil filled container with a air hose to about 80lbs.
I don't know if this would force oil into the prop.

I am not a engine person, but I don't think that it would matter because the is mainly there to push the spring in the prop to change the pitch. It may also provide lubrication, but sense that would happen regardless of the oil pressure against the spring, then there must be some oil reaching you prop when you pre-oil.

Kent
 
Cycle the prop after start up somewhere in the area of 1800 RPM and it will purge itself. I've forgotten what you are building but if it is a taildragger DO NOT do a full power run up without the tail tied down. Please. Larry
 
ok

Thanks for the advices guys.
I'll let the M/T prop take care of itself then.

It's a pity I didn't see that trick about vaseline in time, but I hope the seal is ok.
There was some oil on there before we put the prop on, so hopefully that's enough.

Guess I schould crank the engine some more then, to obtain higher oilpress before first start.

Thanks!
 
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Any indication of pressure should be enough, just fire it up, bring it down to the lowest idle it will stay running, and let it build whatever more pressure it will when you run it. As soon as you see pressure on the gauge, you already have oil throughout the engine, which is the most you could hope for.
 
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