Ball Valves on engine to make raw water draining easier

zellerj

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I was wondering if anyone had good luck or advice on installing ball valves in place of the 1/8 inch plugs on 1980 vintage Mercruisers. Then instead of standing on your head trying to unscrew the plugs, you could just turn the ball valve. You could also probe the opening with a piece of wire through the open ball in the valve. Would this work? Or would the vibration of the engine cause the ball valve to open at un-opportune times.
 

AShipShow

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I have thought about this as well. I wouldn't be so concerned about the vibration as I would be if the seals could take the heat. The drain plugs on my manifolds are plastic, but the ones on my block are brass, and I'm wondering if they are subject to more heat and thats why they're brass.
 

Scott Danforth

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I prefer a simple plug vs a petcock. the petcock or small ball valve would neck down too much making it difficult to probe the drain to make sure its not blocked by crud
 

Bt Doctur

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more to do with the thread size of the brass plug vs the plastic plug.
 

jimmbo

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Most ball valves used in heating systems face far higher temperatures than what a marine engine will provide
 

wahlejim

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My concern would be the crud that comes out at the end of draining and prodding. Trying to close that debris in a ball valve will make the seals fail rather quickly, in addition to the vibrations turning the handle on you. You can get locking type ball valves to eliminate that issue. However, my opinion with boats in general is to not add more failure points, especially ones that allow water to enter the boat. Are the plugs really that hard to undo once per year?
 

wahlejim

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As far as heat goes, they are usually rated to 250-300F. If they get that hot, ball valves are the least of your worries.
 

Bondo

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Ayuh,..... Just another spot to collect crud,..... or leak,.....
 

H20Rat

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The drain plugs on my manifolds are plastic, but the ones on my block are brass, and I'm wondering if they are subject to more heat and thats why they're brass.

Depending on the engine, they are all plastic... Realistically the max temp they will ever reach is about the same as your thermostat, well within the range of most nylon plastic. (usually at least 300 degrees)

Ball valves seem like a bad idea. One more failure point, and you never know what you will find when you stick your hand and head into usually hidden spots of the bilge. Might find other issues that you would have overlooked previously.
 

zellerj

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I have two boats with Mercruisers - a 1988 19 foot Larson 4.3 L that I have to remove a carpeted box to get to the drain plugs and a 1988 27 foot Tiara where with twin 5.7 L engines. The plugs found between the two engines are difficult to get to. Both with Alpha 1 Gen I's. With ball valves it should be much easier. I ordered the ball valves and will try them out and report back. My concerns are that they will vibrate open, but I check my bilge often and will watch the first few times out to see if they start to leak. I will position the handle so that the valve handle will have to move up, against gravity, to open.

The 1/4 NPT ball valves have a ball opening of 1/4 inch, so I will still be able to poke a wire up the valve and clear it of any crude. After the crude is through the valve, cleaner water will rinse out any crude before closing. These valves are rated to 300 F and high pressure, so temperature is not an issue.
 

JASinIL2006

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Be nice if they made some sort of locking clip that would prevent a ball valve from working open. The convenience of opening a valve to drain the engine sounds nice, but I'd be worried about it getting opened unintentionally somehow.
 

harringtondav

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I changed from the pipe plugs to thumb screw (air compressor) drain valves to make life easier. This was after I knew how much water should drain, and how fast. The fancy valves plugged with sand an crud, and I had to remove them to poke out the blockage. I went back to the hex head pipe plugs, and have to poke them clear most of the time. After 22 annual block drains I can do it blind, by feel.
 

AShipShow

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now what would be REALLY slick.... is put a solenoid valve in the bilge with all drain ports running to a manifold that drains thru the valve. Have a button back there, hit the button, and drain the entire engine... downside is, you cant poke and prod the holes in case they are clogged, but I wonder if you drained your motor after every outing, if it would ever actually get clogged...
dunno, just think it would be cool to hit a button and drain your engine lol, especially if you had a transom drain for it. dont even get the bilge dirty...

Capture3.JPG
 

Scott Danforth

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now what would be REALLY slick.... is put a solenoid valve in the bilge with all drain ports running to a manifold that drains thru the valve. Have a button back there, hit the button, and drain the entire engine... downside is, you cant poke and prod the holes in case they are clogged, but I wonder if you drained your motor after every outing, if it would ever actually get clogged...
dunno, just think it would be cool to hit a button and drain your engine lol, especially if you had a transom drain for it. dont even get the bilge dirty...


thats basically the single point drain system that busts blocks that mercruiser has.

rust would probably form faster if you drained after every outing.

I prefer the KISS method - on new engine builds, I add a heat exchanger and only have to drain the manifolds and the line from the PS cooler to the raw water cooler.
 

harringtondav

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now what would be REALLY slick.... is put a solenoid valve in the bilge with all drain ports running to a manifold that drains thru the valve. Have a button back there, hit the button, and drain the entire engine... downside is, you cant poke and prod the holes in case they are clogged, but I wonder if you drained your motor after every outing, if it would ever actually get clogged...
dunno, just think it would be cool to hit a button and drain your engine lol, especially if you had a transom drain for it. dont even get the bilge dirty...


You are definitely an innovative guy, Mad. Flyback diodes, etc. I've read a lot of hand wringing on Merc's 4.5 single point drain system, and it doesn't sound too good. I may get a new boat before I go toes up, but it will likely be a 4.5, which apparently doesn't fully drain to winterization. Ugh. I get sand plugs with most fall winterizing block drains.

I like a full cooling jacket when I start my boat during the summer. From muffs, I know it takes at least 30 seconds for my block to fill and get full water flow out the gimbal ports. So I'd be shy about a daily full system drain. If I ever buy that 4.5, I'd likely be trying a hillbilly hack on their single point system so it fully drains. You may have the solution.
 

tacx

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Ball valves are a great idea. They are not like other valves that do not have a FULL OPEN flow through. Also the engine heat would not affect them. With a straight through wide open passageway it would be easy to poke a wire through the valve to clear sediment.

I like the idea and may try it myself.

Tom
 

zellerj

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Dec 13, 2017
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I tried to install the ball valves today, that have a 1/4 inch NPT standard taper with 18 threads per inch. So I removed the petcock and the threads seemed to be different. Turns out there are two parts to the plug - a drain valve plug and petcock, and all these years have only been removing the petcock. So I removed the petcock from the plug and the threads are not 18 per inch, so the ball valves would not work. Anybody know what the petcock thread count is and is it NPT? [h=1]
s-l500.jpg
[/h] I think I need to remove the plug that the petcock screws into? This is where the standard 1/4 NPT threads come in to play. This plug is sold with red loctite, so it s probably in place with red loctite. How do I remove this plug that is screwed into the manifold and block with red loctite?

Maybe AChris (whose advice I should have heeded) and others are correct, and this ball valve idea that I have is hairbrained. But I already bought 10 ball valves so want to give it a good shot at working.
 

tacx

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Every ball valve i have ever operated or installed had alot of friction in turning on and off. And I have installed many. I would not worry about a ball valve opening on it's own. The locking ones look like an option but then again, it seems you would be defeating the whole purpose of "one hand" easy access. If you have to use both hands to lock the valve handle, then you are not gaining anything. I think you would be just fine with standard ball valves.

please keep us updated on your install. I think it's a great idea.

TOm
 
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