How to Pressure Test Water Jacket on Installed Volvo Penta 5.7GXi (Raw Water Cooled)?

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AirStage
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How to Pressure Test Water Jacket on Installed Volvo Penta 5.7GXi (Raw Water Cooled)?

Post by AirStage »

Hi all,

I recently discovered a very small crack in one of the exhaust manifolds on my boat with a Volvo Penta 5.7GXi engine. I’m planning to replace both the manifolds and elbows, but I’d also like to pressure test the block to be safe.

Since this is an open cooling system, what is the correct way to pressure test the water jacket of the engine block?

I’ve searched the forum and the internet, but most instructions I find are for engines that have been removed from the boat, where everything is blocked off. In my case, the engine is still installed, so I'm looking for a method that works in that situation.

Any advice or step-by-step guidance would be greatly appreciated!

Thanks in advance!
Cobalt 255 - VP 5.7 GXi - 320hp
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bruceb58
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Re: How to Pressure Test Water Jacket on Installed Volvo Penta 5.7GXi (Raw Water Cooled)?

Post by bruceb58 »

Take each hose that goes to the manifolds and connect them with a Tee. On one end of the tee, install a pressure gauge with a schrader valve to be able to put compressed air in(available at Home Depot). Put a plug in the hose that comes up from the raw water pump.

Don't go over 15PSI
2017 R5 350HP Mercruiser Bravo III
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