Are these acceptable leak down numbers?

[Grayson]

Hello all! I have a customer's 2002 RX DI all rebuilt with reman crank and bored cylinders. copper sprayed the head gasket and installed base gasket dry. I just performed a leak down test and confirmed the cooling system sealed, held 5psi for 10+ minutes. The combustion side however, is juuuust barely leaking into the cooling system. Like, I'm talking fractions of a psi in 15+ minutes.. Mabey 3/4 psi. I am not sure if I should order a new gasket, re copper spray it or leave it as is. I would appreciate any input as I am at a cross roads and can't decide what to do. I'm honestly thinking about just running it, but my conscience festers lol. Thanks!

Edit: I want to clarify, when I had my high precision gauge on the cooling side while pressurizing the other side I did not see the gauge move at all during the 3 minutes specified in the manual. I just wanted to see how long it could hold for.

 

[mikidymac]

I never test the cooling system.
The engine should hold 8 psi for a minimum of 10 minutes. If it drops you have a leak that is only going to get worse.

 

[Grayson]

I never test the cooling system.
The engine should hold 8 psi for a minimum of 10 minutes. If it drops you have a leak that is only going to get worse.

Well, I decided to just run it as is and as of now the engine runs flawlessly. 145psi compression on both sides holds forever after getting a couple heat cycles in hopefully sealing the gaskets. My Candoo Pro says everything is normal, no codes thrown. water testing very soon

 

[Boyd12]

"I never test the cooling system." I am not looking for an argument, I am just curious, why not?
"The engine should hold 8 psi for a minimum of 10 minutes." My SD manual for two strokes states 5 psi for 3 minutes. Is this a better test? I have had engines sit for hours and not leak so I dont think time is not much of an issue, once you go past 3 minutes.
"If it drops you have a leak that is only going to get worse." Agreed, they dont fix themselves.
Thanks!

 

[mikidymac]

"I never test the cooling system." I am not looking for an argument, I am just curious, why not?
"The engine should hold 8 psi for a minimum of 10 minutes." My SD manual for two strokes states 5 psi for 3 minutes. Is this a better test? I have had engines sit for hours and not leak so I dont think time is not much of an issue, once you go past 3 minutes.
"If it drops you have a leak that is only going to get worse." Agreed, they dont fix themselves.
Thanks!

On the cooling system, I guess because I have never had one leak in 30 years, the important test that will kill an engine is the air leak.
8 psi is the safe pressure for the seals and will show smaller leaks, same for the 10 minutes. 3 minutes is not enough to see very small leaks like gaskets. And because that it what Group K has always done and he builds some of the best endurance race skis.