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496 air purge system not purging

2006 496HO Mags

This is my first year with this boat and with 496s. I Read up on winterizing with the air pump system, was pretty excited that it seemed easier than laying in the bilge trying to reach all the plugs and hoses on my old 454s. Began winterizing port engine, pumped air into the system. One of the green indicators popped, the other did not. I could hear and see water draining from both sides so I assumed/hoped that maybe the one indicator button was stuck...? I should also note that I was not using the "merc" pump, I was using a small Fox pump meant for mountain bike or snowmobile shocks. I figured it would be enough and seemed like it worked for the port engine except for the 1 indicator that didn't pop. Wondering if a higher volume pump would make a difference?

Moved over to the stbd engine, started pumping but the pump didn't build any pressure. No resistence in the pump, no pressure on the gauge, no green indicators, no water draining. I looked at the air lines as best I could and they look intact and hooked up where they belong. So... Looking for suggestions. Thanks.

Were you pumping or did you hit it with compressed air? I found it worked best with a tank at a low psi of about 30psi Once they pop, lay off.

Quote:

Originally Posted by Keith Atlanta (Post 4653323)

Were you pumping or did you hit it with compressed air? I found it worked best with a tank at a low psi of about 30psi Once they pop, lay off.

That's what I was going to try next. Boat is at a marina and the little pump was all I had on me. Just found it odd that one motor built pressure and drained, the other did nothing, with the same pump. Going to try more air next time I'm down there.

Remember, the pump is NOT DISPLACING the water. All the pump is doing is opening the actuators so that the water can DRAIN out via gravity.

As such, this is NOT sufficient for winterization, especially in the cold NorthEast. The air actuator drain system was designed to LENGTHEN your boating season. You STILL MUST winterize with Antifreeze the way we have being doing so forever. You just don't have to wait for a thermostat to open up as there is no restrictor on the sea water side of the system.

There are DOZENS of threads about winterizing 496s. You WILL have a problem in the spring if you do not do a full winterization especially in your region. There are pockets in the coolers and other areas that will retain water and not drain purely out of the air drain system.

Quote:

Originally Posted by Sydwayz (Post 4653368)

I'm aware.... I never mentioned anything about this being my only step of the winterization....

I would never winterize without putting antifreeze in, but wanted to make sure all the water was out before I filled it. I dont trust the antifreeze alone if there is still water left in the system. I pulled the blue plugs but I would rather do it completely as designed with the air system. I assume pulling the blue plugs is not enough because it's super easy, so why wouldn't people just do that? Or is that enough?

I've read the DOZENS of threads about winterizing but couldn't find any about the air system not holding air, i.e. not opening the drains. Any input on that? Do the actuators get stuck? Maybe i'm not putting enough air in? Do the air lines get dryrotted or cracked? (mine looked ok from what I could see). Do the press fittings lose their seal somehow?

Just making sure you knew the whole story, as many don't.

There are two actuators on each motor, one front port, second aft starboard. Can you see if they are allowing any water to drain out?
When they go bad, they usually fail to the point where the spring/actuator is not holding pressure and they leak. I've never seen one fail closed, but I'm sure it could happen especially if corroded.

I was pretty ridiculously anal retentive when I winterized mine too, so I would pump the actuators open, let them drain, and then I would pull the blue plugs too.

Follow the green and white air lines all the way down to each of the actuators. Make sure they are all connected at both ends. They may have worked their way out, or possibly not connected back again after a service by someone. They are just a push attachment, and their internal O-rings could possibly go bad. There is a chance that the air drain actuator could even been removed, as such was done (owner told me) when I bought my boat many years ago. He lived in Arizona and obviously didn't need it so he just replaced it with a section of 1.25" pipe.

it depends on which year model 496 one has to determine proper winterizations.

and also one can have stuck check/ valves which will hold water as well above those areas for added info.

496 is one of the simplest engines to winterize even if the air systems do not operate.

Broken and or slit air hoses can cause the system to not work as well. Many miss that one.

Very simple to test the system as I use connection adapters to a outdrive pressure tester. This tester is one of the best tools to have in ones box. You can pressure test alot using it.

most of the actuators leak anyways. Especially apps that were moded with higher rpms I get rid of the ones that leak and sell / install a very nice adapter that has its own drain plug in the bottom. depending on access from the builder and year model of the 496 access to the drain plug can be hard to get to. But I would would rather have the drain plug than not. Access does get alot easier when removing the gen 3 cool fuel for those apps..

Quote:

Originally Posted by Sydwayz (Post 4653379)

Thank you, I will check the lines and connections better next time i'm down there. Also going to feed it some more psi and see what happens. I have had water in the bilge that I cant explain, so i'm leaning towards stuck actuator. So if the actuator was stuck open, wouldn't it allow air to pass through the whole system without building any pressure? That's the problem i'm having. Or am I wrong?

If for some reason I can't make the air system work this season, is pulling the blue plugs enough to drain the system by itself? 2 on the stbd side front and 1 port side (water pump).? I also pulled the lowest hose off the water pump and all seems to be empty, I just dont want to leave any water pockets. Antifreeze should mix with any left in there but just want to make sure i'm not missing something no-so-obvious.

Quote:

Originally Posted by BUP (Post 4653412)

They are stock 2006 496s. I am interested in your adapter, as it sounds like I may have a stuck/leaky actuator. Sidewayz mentioned a pipe but I'm having trouble picturing it, I've never had one of these apart before.