165hp manifold water drain plug?

[semo549]

I know this is a silly question but... Is the drain plug on the rear of a mercruiser 165hp manifold a threaded brass plug or is it smooth bore with a pet ****? The reason asking is I get a new manifold but it didn't come with the drain plug. The threaded brass plug that was on my old manifold won't tread into my new manifold. It seams like the hole has a smooth bore. Does anyone know where I can get the correct plug for this? I'm taking it as it must be a petcock type. **My old manifold I had on the boat prior wasn't the right one, thats prolly why the plug won't fit the new one.

thanks for the help guys its greatly appreciated.

 

[ziggy]

Re: 165hp manifold water drain plug?

i've had 2 165's. three manifolds. two originals + 1 new one (aftermarket). all manifolds have had threaded holes and used a plug.
both engine drains have been petcocks.

 

[mkast]

Re: 165hp manifold water drain plug?

It seams like the hole has a smooth bore.

Is there a plastic plug painted over in the threaded boss?

 

[ziggy]

Re: 165hp manifold water drain plug?

or even painted over screw threads with enough paint to make it look smooth..

 

[semo549]

Re: 165hp manifold water drain plug?

no plastic plug in there, I was scraping at it with a small flat head and razor blade to make sure. I'm just going to tap it so I can thread a brass plug in. Thanks for the help. I'm only a year deep into the boating world, I learn something new everyday on this sight!