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Homemade pre-oiler

pazmanyflyer

Well Known Member
Does any one have plans or pictures of a homemade pre-oiler for their overhauled/new engine?
Here's my case...We purchased a rebuild O290 and dad wants to have some type of pressurized system to pass oil through the engine oil passages before we re-install the cylinders. (Cylinders removed to inspect cam, crankshaft and the rest of the case internally.) This way dad, and our AP/AI signing the books, have visual confirmation that the oil passages internally/externally are not blocked. I have ideas but if someone else knows how this can be done I'd appreciate any information, plans, pictures you have on it.

Thanks
 
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Many different tanks........

.....have been adapted, Carlos...from Freon bottles to small fire extinguishers.

Essentially, a way to pour oil in, install a cap/plug, with an air fitting and a hose to attach to the oil pressure sending port and open the valve.

Regards,
 
Two possibilities on this...

1) follow the Lycoming SB on pre oiling...Basically it says to pull the spark plugs and crank the engine until you get oil pressure.

1A) Van's Builders Instructions suggest that you disconnect the oil pressure line at the oil pressure sensor (manifold), spin the engine as above, until oil seeps out of the oil pressure line, reconnect everything, and then proceed with an engine start.

2) In the Orndorff (sp??) videos, his pre-oil procedure was to fill a pump-up plastic 2gal weed sprayer can with oil. Remove the oil pressure line (and the restrictor fitting) from the engine, and adapt a fitting onto the spray can hose that will fit the engine. Put oil in the can, pump up the sprayer, and oil will be forced into the engine and all the oil passageways. I think he indicated that it took several iterations of this, but he put the entire 7 -8 qts of oil in the engine this way.
 
Building a pre-oiler

I got a few emails from the lycoming guys at the yahoo groups and thought I'd post a few pictures of what I'm doing to pre-oil my engine. I'll be buying supplies tonight at my local Home(builders) Depot aviation department. 20-40 psi should be just fine to push oil through the case to check for free and clear passages.









 
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Beware when you disconnect the air hose, whatever oil is left in the rig is going to come right back out at you if it still has pressure :).
 
Pre-oiler

Beware when you disconnect the air hose, whatever oil is left in the rig is going to come right back out at you if it still has pressure :).

Good point Scott. In that case I may use shut off valves on each end.
 
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Pre-oil the engine

1) follow the Lycoming SB on pre oiling...Basically it says to pull the spark plugs and crank the engine until you get oil pressure.

1A) Van's Builders Instructions suggest that you disconnect the oil pressure line at the oil pressure sensor (manifold), spin the engine as above, until oil seeps out of the oil pressure line, reconnect everything, and then proceed with an engine start.

2) In the Orndorff (sp??) videos, his pre-oil procedure was to fill a pump-up plastic 2gal weed sprayer can with oil. Remove the oil pressure line (and the restrictor fitting) from the engine, and adapt a fitting onto the spray can hose that will fit the engine. Put oil in the can, pump up the sprayer, and oil will be forced into the engine and all the oil passageways. I think he indicated that it took several iterations of this, but he put the entire 7 -8 qts of oil in the engine this way.

If I plan on pumping several quarts of oil into the engine through all of the oil passageways, and there is already a restrictor fitting on my oil pressure sender port, what is the next best port to force the oil through? I have an IO-360 A1B6. Thanks.
 
PVC

You can make a "pig" out of PVC pipe and fittings, use a large threaded fitting on one end so you can pour oil fill it, then a 1/8" pipe fitting on the other end to plumb to the engine.
Just make sure it's clean inside as you will be bypassing the filter, any potential good you may do by oiling will be lost from debris forced into the galleys. Keep the pressure reasonable, like 20 psi or less.
Also, pre oiling a newly assembled engine is fine, but if your concern is checking for plugged oil passages...there not going to be plugged. You can spin prime it just fine with the plugs out and 20-30 turns often he prop. Also keep in mind all you are oiling by either method is the crank bearings. Nothing else will get oil until you run it.
Tim Andres
 
What port?

All good information but the revival question was:

WHAT PORT?

I would hook to the oil cooler hose inlet. Plug hose and put the oil there, it will fill the cooler and passages, but not back to the pump ( yes it will back to the pump, but OK see DanH post below). Swap to hose to fill back to the pump.

Use a 3" pvc SCH40 tube, tap the bottom and a clean out screw cap end for filling. I will likely leak air, but that is ok, you will only use it once.

Any thing wrong with this port?
 
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I would hook to the oil cooler hose inlet. Plug hose and put the oil there, it will fill the cooler and passages, but not back to the pump.

Connected to the oil cooler inlet line? Vernatherm port is open, so yes, it will go back to the pump, which is fine.

 
Pre-oil the engine

Here's another thing I am considering, and you can all tell me if I'm crazy or not. If my primary concern is getting some oil on that cam shaft, what about filling the engine to the brim? This would be for initial turning as you build up the engine compartment. You would of course drain and service to proper level before you would consider cranking to start.
 
Fire Extinguisher pre-oiler

My engine guy provided this for pre-oiling.

IMG_4962-M.jpg


I put a couple of quarts of oil in. Connected it up to the oil pressure sender line, then put 50 PSI of presssure in and left it on for 20-30 minutes.

IMG_4963-M.jpg
 
BTW, a reason for using the oil cooler inlet is the oil goes through the filter before to the bearings.
 
No way

Here's another thing I am considering, and you can all tell me if I'm crazy or not. If my primary concern is getting some oil on that cam shaft, what about filling the engine to the brim? This would be for initial turning as you build up the engine compartment. You would of course drain and service to proper level before you would consider cranking to start.

The only way to oil the cam is flip it upside down, take it apart, or run it. You could never fill it enough to submerge the cam.
There is no other way to get oil on the cam. IIRC you have or had the cylinders off, if so you can smear some moly cam lube on the lobes while its apart. And of course before doing that you want to inspect the cam and especially the followers carefully.

Tim Andres
 
Yes it does work

Here's another thing I am considering, and you can all tell me if I'm crazy or not. If my primary concern is getting some oil on that cam shaft, what about filling the engine to the brim? This would be for initial turning as you build up the engine compartment. You would of course drain and service to proper level before you would consider cranking to start.

You can fill the engine entirely. I do it and have done it.
RV-6...you will have to raise the tail to get the engine a tiny bit nose low.
Then fill the crankcase....takes 5 gallons +-. Use cheap car oil....
take breather tube hose and hold vertical. cover with rag.
With top plugs out, rotate engine and add oil until it burps out the top of the breather tube. Once it is full....rotate prop several times to get all surfaces covered in oil. Then drain back down to 8 quarts.
I have done this a few times when my plane has been down for extended time periods. Only way I know to coat the cam. Pre-oilers don't do the cam and pretty sure the oil spray nozzles don't coat the cam either. The Cam is very vulnerable in first starts.
Was thinking about this today before posting and figured this procedure would be hard to accomplish on a A model...maybe have to remove the nose gear!Yikes!
 
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Are you sure?

How do you know you got the oil high enough to submerge the cam?
The reason I say you can't, is because there is no path for air to burp out of the top of the case. The case air vents to the accessory case are well below the cam shaft elevation, so I say you'll always have a big bubble in the roof.

Tim Andres
 
Good point

How do you know you got the oil high enough to submerge the cam?
The reason I say you can't, is because there is no path for air to burp out of the top of the case. The case air vents to the accessory case are well below the cam shaft elevation, so I say you'll always have a big bubble in the roof.

Tim Andres

I am not sure. But, with the engine nose low and the oil burping out the vent tube it has to be very high up if not completely full. Plus, with rotating the engine and the cylinders pushing the oil back and forth, the cam lobes only have to be touching the oil to get coated.
Nose low, air bubble in rear.
Nose high, air bubble in front.
Good enough for me, Your mileage may vary. Just my 2cents.
I am not a engine builder, just a backyard mechanic, so you might be right!
 
Here's another thing I am considering, and you can all tell me if I'm crazy or not. If my primary concern is getting some oil on that cam shaft, what about filling the engine to the brim? This would be for initial turning as you build up the engine compartment. You would of course drain and service to proper level before you would consider cranking to start.

Why not just fog it with an undercoating gun spraying motor oil - maybe preservative oil.

Just spray down the dipstick tube until it comes out the breather. Test it in an inverted 5 gal bucket.

Just a thought. But is it really needed?
 
You can fill the engine entirely. I do it and have done it.
RV-6...you will have to raise the tail to get the engine a tiny bit nose low.
Then fill the crankcase....takes 5 gallons +-. Use cheap car oil....
take breather tube hose and hold vertical. cover with rag.
With top plugs out, rotate engine and add oil until it burps out the top of the breather tube. Once it is full....rotate prop several times to get all surfaces covered in oil. Then drain back down to 8 quarts.
I have done this a few times when my plane has been down for extended time periods. Only way I know to coat the cam. Pre-oilers don't do the cam and pretty sure the oil spray nozzles don't coat the cam either. The Cam is very vulnerable in first starts.
Was thinking about this today before posting and figured this procedure would be hard to accomplish on a A model...maybe have to remove the nose gear!Yikes!

Thanks Bob, I think I will try your method. That's what I was thinking. Burp out as much air through breather tube as possible. Then, even if there is still some air up in the cam shaft space, the splash distance and "head pressure" to overcome approaches zero.
 
If the engine is new, or overhauled, all the bearing surfaces should be covered in assembly lube. I have been told by one engine builder that not having oil pressure for the first start up is a non issue.
 
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