What about rigging up an auto drain for an I/O?

Chris1956

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What is you replaced the manifold and block plugs on a V6 MerCruiser with small diameter (3/32") brass hose barbs. Then you route hoses from the barbs to other barbs installed in the Y exhaust pipe. While running, the motor would leak some water from the block and the manifolds, but it would not be enough to change proper operation of the mannys or the thermostat. After shutdown, the block and mannys would auto drain.

We would still need something to prevent them from clogging from rust, maybe some kind of cone-shaped screen in the block and mannys.

Do you think it would work?
 

Bondo

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Re: What about rigging up an auto drain for an I/O?

Ayuh,.....

Sounds like the path to More Frozen Blocks to Me.....

Personally,...
I see those Single point Drains as the Same Thing.....

Nothing but a False sense of Security....
 

HT32BSX115

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Re: What about rigging up an auto drain for an I/O?

It would absolutely work. you mentioned the problem though, you'd need something to prevent the inevitable rust flakes, sand, and other debris from clogging it.

You'd have to start with a rather large hole at each drain. Large enough to pass the debris then have the "cone" filter. It would probably need to be in some sort of a clear "holder" so you could see when it began to plug up and be easy to remove and clean once in a while..
 

Don S

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Re: What about rigging up an auto drain for an I/O?

Sounds like a recipet for cracked blocks, boat sinkings when those hoses come loose un-noticed, and a lot of other things.
Merc tried a single point drain and an air drain. Still have to take it all apart to make sure it drains.

We would still need something to prevent them from clogging from rust, maybe some kind of cone-shaped screen in the block and mannys.

Screens clog up and there is little room for them.

Best to stick with the KISS principal, it always works.
 

Don S

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Re: What about rigging up an auto drain for an I/O?

The fact that the drain plug holes in the block are only 1/4"NPT tells you that any kind of fitting restricts the hole down to a clogable size.
Would suggest you test it for about 10 years and report back with your findings. :eek: :p ;)
 

180shabah

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Re: What about rigging up an auto drain for an I/O?

Sounds like we may have another candidate for IRS form 1040ST(the stupid tax) :D
 

HT32BSX115

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Re: What about rigging up an auto drain for an I/O?

Best to stick with the KISS principal, it always works.


True of course,

The only sure way to prevent a block & manifold freeze is to ENSURE the water is removed.
 

mylesm260

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Re: What about rigging up an auto drain for an I/O?

Ya, really bad idea.

The factory drain holes are already at the very limit of how small you can realistically have a drain. You start introducing fittings and hoses, and your just going end up with a clog and a cracked block.

Remeber, Boats suck up water from whatever your boat is in. Think of whatever body of water you use your boat in, and imagine all the crap that your leg is sucking up.

Now combine the dirt and grit you pickup with rust, and imagine running it through a 1/8 hole (which is going to be about all you're left with with a fitting in those drain holes).

Now. Let's say that leaves you with about a 30% chance of not getting all the water out from all the areas in you're engine. You wana take a 30% chance of being out 2-6K for a new motor?


Half the people in here are so uneasy about the factory draining system that they go even further, and add antifreeze to their systems, because they're not 100% sure they're getting all the water out of their engines. This is the 2nd year I've owned a boat, and I must admit, I added antifreeze to my engine aswell, but mainly because of the angle my boat is sitting in my driveway.

If you don't like having to pull multiple drain plugs every year, might I suggest switching to a closed cooling system? My understanding is that if your manifolds are older than a few years, that you likely will have to replace your manifolds aswell when you do the conversion.


Cheers!
 

Chris1956

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Re: What about rigging up an auto drain for an I/O?

I did not mean for this system to replace winterizing, but to allow folks to use their in-water I/O boats when the air temp is freezing and the water is liquid. I was hoping for some constructive info, on how it could be feasible in that application.
 

Bondo

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Re: What about rigging up an auto drain for an I/O?

I was hoping for some constructive info, on how it could be feasible in that application.

Ayuh,....

That's the Whole Point,..... It's Not Feasible...
 

mylesm260

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Re: What about rigging up an auto drain for an I/O?

Ya, for that to work, you would need to fabricate a fitting to replace a casting plug. It would need to use like 1/2 heater hose and have a valve on the end.

Anything less than a half inch hose and fitting, and murphy's law would kick in. it would get gummed up, and not drain.

And besides, I seem to remember that the casting plugs are a little higher up than the drain plugs anyway =)


So what you really need to do, is invent a time machine, and go back to the 50's when they started designing the north american small block, and convince them to use a much larger drain plug on the sides of their blocks, so that 60 years later, you can invent a system that will save yourself 15 minutes in winterizing.

=P
 

Howard Sterndrive

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Re: What about rigging up an auto drain for an I/O?

unpainted cast iron rusts like mad when exposed to air. Keep it under water and it corrodes much slower.
I think you would have internal rusting issues... then chunks of rust plugging your drain lines.
 
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