525efi Reversion??
12-13-2018 | 06:30 PM
#1
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From: French Settlement, LA
525efi Reversion??
I just completed a stock rebuild of a 525 Mark Boos @Precision Marine done the engine work. The engine has stainless Marine manifolds pressure tested good. Broken in on the Dyno with no issues. Installed in the boat after idling until the thermostat opened we checked the manifolds and found a small amount of water/dampness in the bottom of the exhaust manifolds. The risers are Stainless Marine risers and checked good when tested with water off the engine. Could this be a reversion issue? Any advice would be helpful. 
12-15-2018 | 03:49 PM
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From: IBX
Sounds like reversion. May not end up being a problem if you used inconnel exhaust valves and try to keep the engine off idle as much as practical. Things other than water leaks that could cause this would be cam incorrectly degreed or an exhaust valve not sealing entirely. I'd run it though and watch for more clues.
BT
BT
12-16-2018 | 08:53 PM
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From: French Settlement, LA
BT, I was thinking the same thing. A couple thoughts, we were running on a hose and the water was cold it could have been condensation as it was very damp air also. I also found a small exhaust leak between the manifold and the riser, according to stainless marine this will cause reversion also. I am going to change the gaskets, use sealant and see how it does. Yes I do have inconel valves, this is my first 525 and I may just be overly cautious.
12-17-2018 | 01:33 AM
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From: Omaha/LOTO
Running on the hose or in the water?
If on the hose, is the boat sitting at the same angle as when it sits in the water at idle?? Bow being down slightly could make a difference.
Its possible that it could just be some condensation as well.
If on the hose, is the boat sitting at the same angle as when it sits in the water at idle?? Bow being down slightly could make a difference.
Its possible that it could just be some condensation as well.
12-17-2018 | 06:38 AM
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12-17-2018 | 07:56 AM
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From: IBX
BT, I was thinking the same thing. A couple thoughts, we were running on a hose and the water was cold it could have been condensation as it was very damp air also. I also found a small exhaust leak between the manifold and the riser, according to stainless marine this will cause reversion also. I am going to change the gaskets, use sealant and see how it does. Yes I do have inconel valves, this is my first 525 and I may just be overly cautious.
12-17-2018 | 10:38 AM
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From: SF Bay Area
When I installed bungs in my headers I pulled the plug off of one that’s about 14” up from where the water mixes and it still soaked my hand. I put the plug back in and checked it later with the engine off and it was dry and sooty.
