Replace metal drain plug?

JASinIL2006

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While winterizing my boat yesterday, I found myself struggling (again) to reach the lower block drain on the starboard side of my 350 Mag. It's a plug that is underneath what I think (?) is the knock sensor. It's the only plug that requires a wrench - a 9/16" - to remove, and the older I get, the harder it is to get a wrench down there, loosen the plug and get everything out without dropping something into the bilge.

My question: is it possible to insert some sort of nipple into that threaded opening and use the standard blue plastic plugs instead of the metal plug? Will that have any effect on function of the knock sensor (or whatever that thing down there is)?

Second question: if I can use a nipple that will accept a blue drain plug, what size will I be looking for? Or even better, if there is a part number or link to nipple, I'd be most grateful.

Thanks!
 

Scott06

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This is the brass fitting that threads into the 1/" npt female port and adapts to the blue plastic plug. I just bought two to replace the ones on my block sides, you can google the PN to find other sources. Only donw side I see if you ever had debris in there it does restrict the opening a bit, but you can just screw it out.. I just replace the plastic plugs every couple seasons for $10...

 

JASinIL2006

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That looks like just what I want! It won't affect the function of the knock sensor to swap this out?
 

flashback

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Last year I put ball valves in the block drains. I have no idea how they will hold up over time but they sure help an old man...
 

Bondo

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That looks like just what I want! It won't affect the function of the knock sensor to swap this out?
Naw,... It'll still be wet on the sensor side,...... it detects through the water,...

Though plugged with debris might cause it not to work right,....
 

tank1949

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While winterizing my boat yesterday, I found myself struggling (again) to reach the lower block drain on the starboard side of my 350 Mag. It's a plug that is underneath what I think (?) is the knock sensor. It's the only plug that requires a wrench - a 9/16" - to remove, and the older I get, the harder it is to get a wrench down there, loosen the plug and get everything out without dropping something into the bilge.

My question: is it possible to insert some sort of nipple into that threaded opening and use the standard blue plastic plugs instead of the metal plug? Will that have any effect on function of the knock sensor (or whatever that thing down there is)?

Second question: if I can use a nipple that will accept a blue drain plug, what size will I be looking for? Or even better, if there is a part number or link to nipple, I'd be most grateful.

Thanks!
I'd replace the plastic with brass or galvanized. There is a hose kit that replace v8 drain plugs that provides a pretty strong hose. On the hose end is a threaded brass cap. Obviously, you can use gravity to drain oil or attach a pump to brass cap.
 

JASinIL2006

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I'd replace the plastic with brass or galvanized. There is a hose kit that replace v8 drain plugs that provides a pretty strong hose. On the hose end is a threaded brass cap. Obviously, you can use gravity to drain oil or attach a pump to brass cap.
I think you’re talking about draining the crankcase of oil… I’m talking about draining water out of the block when winterizing.

I do kick myself, however, for not installing one of those oil drain hoses when I had my engine out. That would’ve made life so much simpler.
 

JASinIL2006

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Well, I’m gonna buy the brass nipple and use a blue drain plug. I don’t relish the idea of having to hang upside down into the engine bay to take out the current plug, but it will be good to not have to do that with a wrench in the hands ever again.

Thanks for the responses!
 
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