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  #21  
Old 08-24-2019, 10:18 AM
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Mel Mel is offline
 
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Originally Posted by lr172 View Post
No, it doesn't. That is a major design no no. That would cause extreme cavitation and the oil would become entrained with air bubbles, reducing the effectiveness of the oil system across the board.
Larry
THIS...is why it is very important to not overfill an auto engine with oil since in auto engines the oil sump is open to the lower end of the crankcase.
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  #22  
Old 08-24-2019, 10:45 AM
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I'm still trying to understand how an external pump is a benefit, when the storage lubrication scheme still depends on spinning the engine with the starter, which brings the internal pump into play. I suppose the additional pressure would increase leakage volumes from the bearings, thus maybe throw a little more oil on the cam.

Personally, I'd seal it and fill it with a preservative oil or oil with additive. Done, every surface protected, zero wear.
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  #23  
Old 08-24-2019, 10:48 AM
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I'm still trying to understand how an external pump is a benefit, when the storage lubrication scheme still depends on spinning the engine with the starter, which brings the internal pump into play. I suppose the additional pressure would increase leakage volumes from the bearings, thus maybe throw a little more oil on the cam.
Personally, I'd seal it and fill it with a preservative oil or oil with additive. Done, every surface protected, zero wear.
I agree!!!
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Recipient of Tony Bingelis Award and Wright Brothers Master Pilot Award
USAF Vet, High School E-LSA Project Mentor.
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  #24  
Old 08-25-2019, 08:43 AM
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Hartstoc Hartstoc is offline
 
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Originally Posted by DanH View Post
I'm still trying to understand how an external pump is a benefit, when the storage lubrication scheme still depends on spinning the engine with the starter, which brings the internal pump into play. I suppose the additional pressure would increase leakage volumes from the bearings, thus maybe throw a little more oil on the cam.

Personally, I'd seal it and fill it with a preservative oil or oil with additive. Done, every surface protected, zero wear.
Dan- You may well be right, But I wonder if you really can completely fill a mounted engine all the way up to the cam, or if entrapped air would prevent it. You would also have to put up with a lot of oozing past imperfect seals around valve stems, etc. Then you would also have a lot of oil in cylinders and induction and exhaust system to burn off when first running the engine.

My hope was that artificial circulation of a large volume of oil concluding with a good spin of the starter would coat all surfaces thoroughly , including the cam, but removal of at least one jug would be required to verify that. Conventional wisdom assumes that the meager output of the engine pump is all you have going for you when just cranking the engine. I was able to see that the cylinder walls were fully coated with fresh oil using a mini camera. I did at least get a good feeling from purging air from a new filter and circulating fresh clean oil through all of the oil galleys and bearings and lubricating the rings. I have other fluid transfer needs that justified the cost of the pump.

I’m really just trying to explore and learn more about this topic. I didn’t anticipate that my engine would be down for so long a time when I took it out of service, or I’d have done more in the way of running preservative oil, etc, so I’m looking for ways to protect an engine that has already been sitting quite a while. I guess I’ll have to pull a jug if I want to bring this to a full conclusion.- Otis
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Last edited by Hartstoc : 08-25-2019 at 09:05 AM.
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  #25  
Old 08-25-2019, 08:53 AM
lr172 lr172 is offline
 
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Originally Posted by Hartstoc View Post
Dan- You may well be right, But I wonder if you really can completely fill a mounted engine all the way up to the cam, or if entrapped air would prevent it. You would also have to put up with a lot of oozing past imperfect seals around valve stems, etc. Then you would also have a lot of oil in cylinders and induction and exhaust system to burn off when first running the engine.

My hope was that artificial circulation of a large volume of oil concluding with a good spin of the starter would coat all surfaces thoroughly , including the cam, but removal of at least one jug would be required to verify that. Conventional wisdom assumes that the meager output of the engine pump is all you have going for you when just cranking the engine. I was able to see that the cylinder walls were fully coated with fresh oil using a mini camera. I did at least get a good feeling from circulating fresh clean oil through all of the oil galleys and bearings and lubricating the rings. I have other fluid transfer needs that justified the cost of the pump.

I’m really just trying to explore and learn more about this topic. I didn’t anticipate that my engine would be down for so long a time when I took it out of service, or I’d have done more in the way of running preservative oil, etc, so I’m looking for ways to protect an engine that has already been sitting quite a while. I guess I’ll have to pull a jug if I want to bring this to a full conclusion.- Otis
Many engine experts indicate that a good portion of "normal" metal to metal wear over the life of an engine (excluding break in wear, of course) comes from the starting phase of running, when gravity has removed a good portion of oil film that can't be replaced until high Idle rpm is reached and enough time elapses for splash lubrication to replace it. This would support the general consensus here that your not likely to see much help from splash lubrication at starting RPMs.

I am with Dan here. A lot of effort for an unlikely benefit. We see most corrossion in the barrels and cam/lifter interface. These are the two areas that are quite unlikely to see oil from your proposed method. Bill's approach is pretty simple to deploy and virtually fool proof. You can't have corrossion without moisture.

Don't forget that the sytech starter has a VERY small duty cycle. Less than 5 or 10%, if I remember correctly.

Larry
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Last edited by lr172 : 08-25-2019 at 09:02 AM.
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  #26  
Old 08-25-2019, 09:20 AM
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Originally Posted by lr172 View Post
Many engine experts indicate that a good portion of "normal" metal to metal wear over the life of an engine (excluding break in wear, of course) comes from the starting phase of running, when gravity has removed a good portion of oil film that can't be replaced until high Idle rpm is reached and enough time elapses for splash lubrication to replace it. This would support the general consensus here that your not likely to see much help from splash lubrication at starting RPMs.

I am with Dan here. A lot of effort for an unlikely benefit. We see most corrossion in the barrels and cam/lifter interface. These are the two areas that are quite unlikely to see oil from your proposed method. Bill's approach is pretty simple to deploy and virtually fool proof. You can't have corrossion without moisture.

Don't forget that the sytech starter has a VERY small duty cycle. Less than 5 or 10%, if I remember correctly.

Larry
More good points , Larry, but note that I’m flowing a LOT more oil than can be achieved with the starter, and that with plugs removed and a very powerful battery, my B&C starter was cranking pretty close to unloaded RPMs, so I think I'm creating a new condition worth exploring here. The starter barely got warm during several 15 second cranking cycles. I did see a fresh oil film on the entire cylinder walls after the spin, so if oil is getting splashed there it may be getting splashed on the cam as well. There are no “return lines” in the oil system, controlled leakage around bearings is how oil gets back into the sump. The rod big-ends pass very near the cam with each revolution, and oil is being forced out around the big end bearings continuously. I still think this is a question worth asking, but have to admit to an abundance of ignorance about what is really going on in there!- Otis
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RV-7A (bought)
Built Monnett Moni
Frmr Test Pilot/Author CAFE APR's:
RV-8A, S-7C, Europa, Glastar.
-2019 VAF donation!!-
"RV-Fun is inversely proportional to RV-Weight!"

Last edited by Hartstoc : 08-25-2019 at 09:23 AM.
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