Understanding Montana plumbing

[David T. MacNeill]

We learn more about our “new to us” 2001 Montana Big Sky 3280 every day, but one system has me scratching my head. I am not a particularly “handy” type and lack the tools and facilities to take the bottom off and look around, locating the pipes, drain valves, and the four tanks — or five including the water heater? I want to visualize and understand how it all works together, both on shore water and off. I don’t really understand how to fully drain everything before the snow arrives.

Anybody willing to enlighten me by answering a few specific plumbing questions? Yes, I have read a number of threads on this topic and it only generated more questions.

[beeje]

Bring on the questions.

[DQDick]

Just to start, your water heater either has an anode rod or a drain plug on the bottom of it. Remove the cover on the side of your rig and remove that plug or rod and your water heater will drain. If you have an anode rod and it's used up replace it. Somewhere on your rig you should also have low spot drains, probably two hoses coming out together with valves just above. On the newer rigs they are in the convienence center, but I don't believe models as old as yours have convienence center.

[bigred715]

I also suggest you flush your hot water tank. You will find a lot of sediment from the action of your anode rode. A white granule substance. I do mine at least once a year.

[David T. MacNeill]

Originally Posted by beeje

Bring on the questions.

I’ll begin with what I do know, or at least I think I know:

When on shore water, the system is pressurized including the water heater, but the fresh water holding tank is not. That has to be filled from the outside. Once the shore water is disconnected, you must turn on the pump switch on the galley wall panel so the system can pressurize from the fresh water tank.

I know how to drain the water heater, the galley tank, the grey water tank, and the black water tank. How do I drain the fresh water tank? I can hear the pump running but almost nothing comes out of the sinks, shower, and toilet. The tank indicator on the galley wall panel shows the fresh water is full. Is the pump not priming? How do I prime it? Do I have to do something to the pump? Is there any other way to drain the fresh water tank besides running the faucets and toilet? Should I be running the pump while on shore water until it primes itself?

I can see one low point drain. Looks like a short tube with a sideways white plastic screw cap. I haven’t opened it up because I don’t know which tank that water drains from.

[beeje]

Ok this may be a long reply so bear with me.
-I believe most montanas fresh water tanks are over or behind the axels.
-The drain to that tank should be a single pipe hanging below the underbelly with either a cap of a valve on it.
-There will be 2 pipes, (usually together) with valves or caps ,those are your low point drains. If you open up (turn on all faucet's) while not hooked up to a water supply or not drawing water from the fresh water tank, most of the water will drain from the water lines.
-If you are hooked up to a water supply you do NOT need to turn on the water pump.
_If you have water in the fresh water tank and are not hooked up to a water source, you must turn on the water pump switch to pump the water (no need to prime, turn on a faucet and wait for water to come out).
-After you get water to come out of the faucets and you turn them off the pump should stop running. If it does not, you have some kind of leak somewhere.

Sounds like you have a lot to learn, and everyone here will do whatever they can to help you out so keep the questions coming.

You are dealing with a 16+ year old camper that may or may not have been taken care of functioning properly.
Pump may be bad/you may have broken pipes etc.

[David T. MacNeill]

Originally Posted by beeje

Sounds like you have a lot to learn, and everyone here will do whatever they can to help you out so keep the questions coming.

Thank you kindly for these details. I’ll look for that fresh water drain. It may be the single short pipe with the screw cap I mentioned. Only one way to find out, I guess.

I am concerned that there is some issue between the fresh tank and the pump, most likely an air leak preventing the pump from sucking water. I’ve let it run for many minutes and nothing comes out the faucets or anywhere else. The rest of the system works fine on shore water.

I have definitely bitten off more than I can chew in buying this rig, but I can learn. Honestly, I’d be lost without this forum.

[David T. MacNeill]

Originally Posted by DQDick

Somewhere on your rig you should also have low spot drains, probably two hoses coming out together with valves just above. On the newer rigs they are in the convienence center, but I don't believe models as old as yours have convienence center.

So the convenience center, if I have one, is under the rig, not the switch and light panel in the galley?

[psomers]

Best is to get someone that knows Montana to help you. It will all make sense when explained. Your fresh water tank may not have any water. The full indicators lie a lot.

[David T. MacNeill]

Originally Posted by psomers

Best is to get someone that knows Montana to help you. It will all make sense when explained.

I would gladly pay for an hour or two with someone who really knows Montanas. Anyone one in the greater Boise area interested? What I DON’T want to do is just drag the Monty to Camping World and have them quote me a $2500 repair. I can’t afford it and so would much prefer to do as much as I can myself.

[beeje]

Obviously make sure you have some water it the fresh water tank. There should be a white cap about 1 1/2 in diameter, Probably behind a small door at the rear of the camper on the drivers side.

You are correct, if the pump is sucking air you will not get any water. Check for loose connections every where. Mostly around the pump since it would be on the suction side where the issue is. If the issue was on the pressure side you would have a leak.

If you had a convenience center it would be obvious to you. It would have all or most of your water connections/dump valves/TV hook ups/outside shower in one place behind a large compartment door.

Open up all your doors and post some pics of all sides of your unit. That will help in determining what you may or may not have and where things are located.

[psomers]

Originally Posted by David T. MacNeill

I would gladly pay for an hour or two with someone who really knows Montanas. Anyone one in the greater Boise area interested? What I DON’T want to do is just drag the Monty to Camping World and have them quote me a $2500 repair. I can’t afford it and so would much prefer to do as much as I can myself.

I would think 99% of Montana owners would be happy to help you for free. Boise is a little too far for me but bet Boise has hundreds that would help.

[Former StClairSailor]

David,

You can do an advanced search from the home page. Click on Community, then from the drop down click "Members List". Right above the list of names on a brown line at the far right you will see a box that says Search Members. At the bottom of that box you will see "Advanced Search" . Click on that and it brings up a list of fields to select from. Click the drop down on State/Province and select Idaho. You will find 107 members from Idaho, 14 from Boise. Look through the list and you can find other cities near Boise as well. You can send one or more of then a PM (personal message) and I'm sure you will find one of them to assist. Best of luck and let us know if we can further assist.

Originally Posted by David T. MacNeill

I would gladly pay for an hour or two with someone who really knows Montanas. Anyone one in the greater Boise area interested? What I DON’T want to do is just drag the Monty to Camping World and have them quote me a $2500 repair. I can’t afford it and so would much prefer to do as much as I can myself.

[CORattler]

Excellent suggestion John!

[David T. MacNeill]

Originally Posted by beeje

Open up all your doors and post some pics of all sides of your unit. That will help in determining what you may or may not have and where things are located.

I’ll take photos as soon as I can. Much better than a thousand words.

[David T. MacNeill]

Originally Posted by beeje

Open up all your doors and post some pics of all sides of your unit. That will help in determining what you may or may not have and where things are located.

You’re right. Once I saw a convenience center on a newer Montana it was obvious my 2001 doesn’t have one.

Well, found the fresh water tank drain. It was right in front of me all along. Stupidly, I thought since the drain was right under the water heater it must be the water heater drain — DOH! I’ve since learned about my Suburban water heater and how to drain and maintain it. Will I need to buy a 1” socket or a 1-1/16” socket? Looks like 1” to me but the RV Geeks video I saw say Suburban uses a 1-1/16”. (See first photo.)

So the second photo of the fresh tank drain valve, and next to it is what I’m assuming is the hot water low point drain. The third photo is what I believe to be the cold water low point drain. It’s on the driver’s side of the coach, right under the basement door. Will test them tomorrow.

[beeje]

1st pic is the water heater drain. I don't know the exact name of the device but you can buy a combo anode rod /drain device so all you have to do is spin it to let the water out (looks like the valve on an air compressor). I drain mine after every trip and never keep water in the heater. No tools necessary once installed.

2nd pic are you low point drains. These drain water out of you water lines. 1 is hot and 1 is cold. Looks like they need some new valves. If you open up all your faucets when the drain valves are open most of the water in the lines should come out.

3rd pic is your fresh water tank drain. Open up or remove the cap to all the water out of the tank. I always open mine right before departing a camp site and leave it open while going down the road to make sure it is empty when I get home. I do not leave any water in the tank while the camper sits and waits for the next trip.