Size does matter

[bennu36]

So does anyone know the size of the fresh water tank drain plug? I would like to get a new one before I attempt to take the old one out. Last year I just pumped it as dry as I coudl and then put a little RV antifreeze in it, worked ok. This year I have a plan to use the pump to run antifreeze through the line with out putting it in the tank. If it works I will share my procedure with you all.

[toskeysam]

Wish you luck getting to the suction line without taking the pump loose from the floor!

[SteveH]

I believe they make a kit for that. It allows you to draw antifreeze out of a bottle on the intake side of the pump.

[toskeysam]

Got the kit...it is still in the wrapper. The Interstate (at least my 2013) pump is a royal pain to get at. Tried an alternative method this year...so far so good.

[PSchw]

This is a mayor undertaking. I attempt this last week. No problem to get to the suction side but it is quick disconnect so the standard kit does not work.
If you down there pull the filter on the suction side and clean it out I was amazed how much installation debris it had.(
I run the tank dry and the removed the plug but almost nothing less then 2 ounce came out.
I choose not to put any antifreeze into the line or pump but I blow it out real well and keep the low point drains open so it can dry out.


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[bennu36]

You have discovered my plan , sort of . I am making my own "suction kit" many years ago I bought the same make if not the very same model of pump for my boat's fresh waters system. It came with a numbers of the quick connect fittings I paln to use those. They came in individual packets with the part number on them when I figure out which is best I will publish the part numbers for you all.

[PSchw]

Sounds good. On the suction side is a small filter with the same quick disconnect.
Thus optional auction line is also good for spare water.
Looking forward to your details.
Thanks
Peter


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[jennian]

Your local RV or marine supply should have a 90 degree fitting that will fit the quick connect on the pump and a std hose on the other end. Just release the quick connect at the pump remove the filter screen fitting for cleaning and storage connect the 90 fitting and hose to pump the antifreeze via the pump

[c21]

Originally Posted by bennu36

So does anyone know the size of the fresh water tank drain plug? I would like to get a new one before I attempt to take the old one out. Last year I just pumped it as dry as I coudl and then put a little RV antifreeze in it, worked ok. This year I have a plan to use the pump to run antifreeze through the line with out putting it in the tank. If it works I will share my procedure with you all.

3/4" NPT. I put a street elbow and pvc ball valve on mine. Installed valve with the handle on top for extra clearance. Cheap fix and works great.

[Protagonist]

Originally Posted by c21bill

3/4" NPT. I put a street elbow and pvc ball valve on mine. Installed valve with the handle on top for extra clearance. Cheap fix and works great.

That should be the same thread size as a garden hose, right?. If so, I'm thinking of maybe replacing the plug with a quick-disconnect with check valve, so all I have to do to drain the tank is snap a short section of hose (with the other half of the quick-disconnect) onto it. And it wouldn't stick down any farther than the existing plug the rest of the time.

[rmkrum]

Nope 3/4 MPT is not the same as a garden hose fitting--but adapters do exist.


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[73shark]

The fresh water drain tank plug is a 3/4" straight thread, not an NPT.

When mine is screwed in all the way, it only protrudes about a 1/4". Since it only takes about 30 seconds to remove it, not sure I would want to add a valve and reduce the ground clearance that much.