Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

[qflyer]

I have an 06 SeaRay 220 Select that I use year round. I'm in north AL, so the temps drop below freezing a few nights per month this time of year. I can reach the plug to drain the motor easily, but the two plugs on the water pump are nearly impossible to reach. Rather than a plug, I'd like to put an adapter on it so I can attach a short hose and then plug that so it's easier to reach. The problem is, the plug has a coarse thread (13TPI) rather than a more standard 20TPI. I've been to every auto parts and hardware store and nobody has a 1/2-13 threaded adapter - just the finer pitched 20TPI. First, if I can find something that will screw into the pump to attach a hose to, will there be any negative effect? If not, any suggestions on where I can find the right parts to do this, or better suggestions?

Thanks!

 

[Bondo]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

Ayuh,.... Welcome Aboard,....

Searay builds boats, Not motors, 'n drives....

What are We talkin' 'bout,..??

 

[achris]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

....

What are We talkin' 'bout,..??

Maybe the thread title is a give-away...

 

[etracer68]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

If its a drain plug, I would supect it being a tappered pipe thread. Most likely 1/4-18 NPT.

 

[Bondo]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

Maybe the thread title is a give-away...

ooops,...:facepalm:

If We're talkin' 'bout the blue plastic plugs, yer not gonna find a plumbing fitting that fits it's threads...
Pull the adapter it goes into, 'n ya should be lookin' at 1/4" pipe threads...

 

[scoflaw]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

OP has a good idea if it's possible, I've got the same issue. Problem being, there is no adapter, and the blue plugs srew directly into the brass pump housing.

 

[Pete104]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

Even if you made something to fasten a hose too, the hole would be so small, the slightest debris could clog it.

Have you thought about a heater?

 

[qflyer]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

Even if you made something to fasten a hose too, the hole would be so small, the slightest debris could clog it.

Have you thought about a heater?

That's something I hadn't thought about...good point. I'd still be willing to try, and if it ever clogged up, obviously I'd have some work to do.

It is the blue plugs that I'm trying to replace, and after talking to several mechanics, boat shops, auto parts, and hardware stores, it appears that the only option is to have something machined for it. Just seems like there would be something out there to make this a little easier for a fat guy like me!

 

[Pete104]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

I know the plugs your refering too.
How cold do you actually get? How long?

 

[qflyer]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

I know the plugs your refering too.
How cold do you actually get? How long?

Usually highs in the 40s with lows in the mid twenty's a couple nights a week.

 

[Pete104]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

Magnetic oil pan heater would give plenty of heat. I found the 1 I use for my vehicle on a site in Minnesota. I'm at the Wis/IL border. They came in various amps as well as different applications.
GOOGLE oil pan heaters or cold weather protection & see what out there.
Or go with a 60 light bulb, but that maybe hard to find by next year!

 

[wellcraft-classic210]

Re: Mercruiser 5.0 water pump drain plug replacement with adapter for easier draining

Qflyer
If you are sure that its .500 in. Diameter (+/-.005) in. and 13 threads per inch?

If so then its most likely a standard 1/2 bolt coarse thread or UNC. It should be easy to verify if in doubt using a 1/2 inch nut with your plug or a 1/2 bolt on the threaded hole. Just be sure not to force anything.


Pipe threads specs for 1/8 are 27 TPI / .405 .in Dia and 1/4 is 18 tpi / .540 .in Dia and they are usually tapered as well. I suppose its possible you have some sort of metric thread as well.

Once you are sure about the thread details i have this suggestion.

I have used a drill press to fabricate this sort of thing. Its actually not to hard. I just made 1 in 3/8 unc thread to use when pressure checking and filling my outdrive.

If you can get a bolt that has a partially threaded shank, cut the head off & some threads as needed, place the shank in the drill press chuck and a drill bit in the vise preferrably with a v bolock or at least chacked with a square to ensure its vertical. The bit will self tend to self center itself on the bolt. Start with a small bit such as 1/8 & work your way up in size. A 1/2 hose should fit & seal nicely on the inthread portion of the shaft.

A metal lathe is better yet for a job like this but Drill presses are more commonly available.

Is this a Chevy 5.0 litre? I ask because my 5.0 chevy has an Inlet hose that leaves at the lowest point. Also thier are some other places water can collect and cause issues. I usually pull all the drain plugs and backflush EVERYTHING TWICE with RV antifrezze to be sure. If you do not want to go through all that on a regualar basis then some sort of engine heater sounds like a better option.