richard5933

Heat welding works well and is often a permanent repair. Bill is correct - getting things cleaned first is key, otherwise you'll just incorporate the dirt in the repair and a leak-free repair will be almost impossible. My tanks were custom built in 1974 from 3/8" thick polyethylene sheets. The pieces were heat welded together. Except for one 6" stretch of an upper seam which looks like it was missed at the factory, the tank is still leak free and going strong (knock on wood). I repaired the 6" piece of the seam and it has held tight since. Hopefully the repair in this thread will last a long time and you'll be able to avoid buying a new tank.

Great job on the repair. What type of plastic welding did you end up with? I've got one which is a very narrow/concentrated heat gun with a metal foot for feeding the 'welding rod' into the seam. Curious to see photos is you've got any of the repair. It's nice to see how others do this since I'm sure I'll have more repairs in the future. Correct - and spin welding is basically another form of heat welding. In the video the Dremel is used to spin the welding rod fast enough that friction heats it up enough to melt it into the substrate. When fittings are installed with spin welding it's the same thing - spin them fast enough so that they melt into the tank surface.

Do you have that right? I thought that poly was heat weldable and ABS was able to be solvent glued. There are special solvent glues made just for ABS. If the tank is ABS then it's a much easier fix. If it's the tank itself that's leaking. PVC is a totally different type of plastic and has specific solvent glues.

Haven't used Water Weld - might work based on some online reports. First stop would be a to determine what the tank is made of and then to use the appropriate product. Depending on where the actual leak is, it might just be a mechanical issue (loose sensor fitting, etc). Heat welding would be a good solution for someone able to do it, but if an adhesive or sealant is available which is safe for drinking water that will bond with the tank that might work as well.

From the JB Weld site: Q:Is there anything that J-B Weld WON’T bond to? J-B Weld will not adhere or bond well to: Any flexible rubber surface, Leather, Vinyl, Canvas! Polypropylene plastic, Polyethylene plastic Nothing will stick well to poly tanks. That's why they use heat welding or spin welding.

Does J-B make a product that sticks to polyethylene?

With a few assumptions since I don't know what the specifics are yet... Where is the leak specifically? Is it on the spin-on fitting or is it in what connects to the fitting? If the leak is in the tank or the spin-on fitting, it will be difficult to find a sealant or epoxy which will stick to it for more than a few minutes. Really hard to bond to poly, which is why they use the spin-on fittings. If you just gubber it up with silicone or sealant of some type, you'll make it really difficult to do a proper seal on it later on. For pin-hole leaks, I have had some success using a clean soldering iron to carefully melt the plastic around the leak and create a seal. If you want to try this, there are lots of YouTube videos. Make sure that the plastic is bone dry and as clean as you can get it. It's possible to make the situation worse quickly with this method, so proceed with caution if you are uncertain. If the leak is in the sensor or where the sensor connects to the spin-on fitting, then the solution would probably be easier but depend on how the sensor is connected to the fitting. Perhaps you can post a photo of the sensor/leak? Also, a few more details like the make/model of your RV and the specifics on the sensor would help us help you.

Sorry - long day today. 97 psi.

Pretty much, yes. All tires are showing a few psi higher this year than last. I use the same gauge to fill them as last year, and then I used the same backup 'master gauge' to confirm that I wasn't crazy. The Tireminder is consistent and still shows if pressure goes up or down, but it definitely is showing a higher pressure than last year even though the tires were filled to the same exact 95 psi.

Just a brief report on a problem I found last week and what I did to fix it. Our shore power receptacle and cord were installed using an older style Hubbell connector. Since there is no screw-down locking ring, I've gotten into the habit of checking to make sure it's firmly in place when I walk past it by giving it a little turn to the right. Last week I did that and found it slightly warmer than normal, even though I was only running basic equipment (fan, charger, and some lights - no a/c). The warmer connector led me to do further inspections. Voltage at the outside of the receptacle was 120vac. Voltage 5 feet away at the manual transfer switch was only 117vac. I'm guessing that the 3 missing volts were to blame for the heat in the connector. I decided that it was time to bring the coach at least somewhat to the modern world and install a new Marinco 50-amp receptacle. Since Custom Coach had cheated and used the chassis/shell for the ground conductor, I was also going to take the opportunity to upgrade the lead from the receptacle to the transfer switch to 4-conductor. This allowed me to install a proper ground buss bar next to the breaker panel and to properly ground the circuits. What surprised me was to find that the cable connecting the shore power receptacle to the transfer switch was only 8/3, yet it was being used to carry 50-amps per leg. Really surprising since they used 6-ga conductors between the transfer switch and breaker panel. The insulation on the individual conductors cracked as soon as I bent it to remove the old conductors. Now I suspected that the heat has been a problem in the past and caused the insulation to fail. Luckily I caught this before anything caught fire or caused a short. New receptacle and 6/4 cable installed. The whole thing is a good reminder that this type of issue can be hidden anywhere, especially in older coaches and RVs.

Is the only symptom higher temp on one side? If so, have you thought about a hub/bearing issue? A failing hub/bearing can create high temp issues. Not sure if you have oil or grease in your rear bearings, but if they are oil then checking oil level might be a good idea.

Interstate Power Systems has road repair trucks. They work on most chassis types and are dealers for most common engine/transmissions. Their territory covers from Indiana all the way west to Montana with various locations. They've worked on both of our coaches and do great work. While most of their customers are commercial trucks and buses, they do work on motor homes and I've seen many in their shop here in Milwaukee. http://www.istate.com/locations

The FMCA Roadside Assistance is run by a third party company. The information you received when you signed up should have a phone number for them. I'd call them directly. When I had a question and called I had to leave a message, and someone returned the call within the hour.

I'm not really looking to camp in a tent by a stream. Not really sure where you're going with all this. Besides, if I boon dock near a moving stream I'm pretty sure that even the FMCA roadside assistance wouldn't cover me getting pulled out of the mud. I started this thread because I thought others might find it interesting. I wasn't asking for a solution, I wasn't complaining about anything, and I wasn't even asking for suggestions on what else I could be doing other than what I did. I simply thought that someone might find interest in the process I went through and the results I got. We each have our own way of doing things, a budget that limits spending, and our own priorities in how we set up our rigs. In this case, I wanted a quiet and simple way to make hot water without running the generator. The parts were already on hand, so I gave it a try. Then I posted the results.

I actually have one of those that we carry just in case. I'd be in trouble if a shower was needed and I was totally unable to produce at least a little hot water. Wouldn't want to rely in it for more than backup use though. Here's something I found today which might actually have a place in my system: https://www.amazon.com/Whale-Gallon-Hot-Water-Heater/dp/B00XCIJN78 It's only got a 300w element and is designed to run on 12v. This would pull only about 30 amps from the batteries, something that the solar could keep up with on its own. I'm thinking that it could be installed next to our existing 120v water heater. It could be installed parallel to the existing water heater and a single diverter valve would determine which water heater was being fed from the cold water supply. Not saying I'll do this tomorrow, just that it's an option for the future.

We have a large rubber hose connected to our fresh water tank which is used to drain the tank. It has been annoying since it tended to flop around and not stay put. I looked for some type of clips to hold it against the partition next to it, but didn't find any. Then I remembered I had some Kydex left over from a knife sheath project. I was able to cut the Kydex to size, heat it, and then mold it to fabricate a few clips. Works well and now the hose is neatly tucked away. Thought I'd post this to spark other creative uses of Kydex plastic.

Most RV water heaters normally use about a 12x12 opening for the access panel. Since I can open the door to gain access, I'd only have to make the opening large enough for the air intake and exhaust output. However, I would then have to fabricate some type of collar to go between the water heater and the door once it closed. Since the door has thickness due to the multiple layers, I'd also have to build a collar on the door itself to direct gases outwards. Of course, most of the units would end up with the venting positioned at the portion of the door which has the center hinge for the pantograph action, making things ever more difficult. I've played with the specs on the various RV water heaters for quite some time on this, and none would work without substantial modifications to either the location of the water heater, the plumbing, the door, or some combination of all three. For all these reasons, I'm still on the lookout for a water heater which can be remotely exhausted through the floor. Seems like someone would have taken the high-efficiency style water heaters used on residential units and adapted it for use in a motor home by now, but I guess that most wanting to do that have just gone to tankless water heaters. Another option I've toyed with is going with a Webasto type unit which could make both domestic hot water and provide space heating. Right now we've got a working traditional LP furnace, but if/when it gives out I have enough space to install a Webasto. It could send a loop through the motor-aid coil in the Seaward to make domestic hot water, and I could use a air-heating coil to provide space heating inside the coach on the existing ductwork. Of course, Webasto systems tend to be pricey, so I'm not in a rush to do that. Probably could just install a modern quiet/smooth generator for about the same cost as the Webasto. Good thing I enjoy all this designing and experimentation. For me it's part of the enjoyment of owning a coach like ours.

Here's what the current water heater setup looks like. They mounted it on a riser since the waste tank discharge goes underneath the water heater. If you look at the photo of the door, you will see that the pantograph door setup results in a multiple layers of door on the upper half (inner door/outer door), with two rubber hinges going across the door. It is possible to vent through the lower section of the door, but it's too low for standard RV water heaters. Also requires quite a bit of fabrication since the aluminum is double layered on the outer door. Beyond my pay grade.

Last time I had to carry in and then install a refrigerator, I used 1" wide webbing straps to lift and move the thing around. Movers use straps like this all the time, and they make things much easier. I think you can find these things in box stores now as well.

Might help in warmer weather, but not while underway of course. Not sure I'd get buy-in from all involved on something that required changing the plumbing to make hot water. I wanted to see if something could be done at the flip of a switch, and apparently the answer is sort of.

What year is the coach?

I was posting more to report how things went than to ask questions about water heaters. Thought others might find it interesting, especially the part about the 15% loss.

We do a lot of dry camping. When we do use water, we use it often on what others would call a trickle. We can make our 80 gallons last a week for two people.

I looked into that one, but it seems that our low-flow situation won't be enough to trigger the burner. There is also a problem on thankless heaters when you use the on/off feature on the shower head. I'm surprised that no one makes a traditional water heater with a floor exhaust or possibility of remote mounted exhaust/intake.

Now that we've got our solar and inverter configured and running well, I thought it was time to push the limits and do some testing. The system is comprised of: Four L-16 batteries providing 780 Ah of capacity, Samlex PST-2000-12 2000W inverter, Victron battery monitor, and 540 watts of solar charging at 30 amps. There is also a battery-to-battery charger which allows for pushing 70 amps @12v to the house batteries from the 24v chassis system while underway. We have a Seaward 120v-only 6-gal water heater. It has a 1500-watt element which takes about 30 minutes to bring the water from cold to shower temp. Our generator is a Kohler 12.5kw powered by a Perkins diesel, and our house battery charger is a Progressive Dynamics 9270 putting out a max of 70 amps @ 12v. My goal was to be able to make hot water when we are dry camping without having to run the generator. I hate the noise of the generator, and the vibration of the Perkins puts my nerves on edge. We've done all we can to quite/calm it down, and I believe we've explored that route as far as possible. A newer/quieter generator is not in the budget at all. What I did was use a small manual transfer switch to enable switching the power feed to the water heater between the main shore/gen system over to the inverter. For most of the time, it will be left powered by the shore/gen system. But, when we have solar deployed and running under the sun or while we are underway and charging from battery-to-battery charger I can now switch to power the water heater from the inverter. The inverter seems able to provide power to the water heater well. Watching the monitor for the inverter and the battery monitor, I was able to see a great demonstration of the loss involved in the process. The inverter was outputting 12.4 amps @ 120v, and the battery monitor showed a draw on the batteries of 150 amps @ 12v. That's about an 85% efficiency in the process, which seems to be about normal. This somewhat hidden 15% loss might explain why some running residential refrigerators don't get the run time they expect based on wattage and amperage calculations. On a fully charged battery bank, I should have no problem heating water for a shower. Would not want to make this my normal routine, but it's nice to have the option when I don't want to hear the noise of the generator. To answer the obvious question - Yes, I have looked into installing an LP water heater. Problem is they all require venting out the side, and due to our pantograph doors on the bays it's not that easy to install anything requiring sideways venting. The only through-the-floor vented water heaters I've found are tankless, and since we dry camp a lot they are not an ideal setup - they don't do well with extremely low-flow showers or when taking Navy showers. The whole project cost me nothing more than a few feet of wire to connect things. I already had the small transfer switch in my parts bin. I consider this a successful project, although possibly of somewhat limited value.