Stinky stinky Class A motorhomes

[ga traveler]

Originally Posted by lonfu

Fire??? it is a water pump.... short cycling causes the high temps... I've personally never seen one to hot to touch... but I have old calloused hands...

shurflo pumps are very well built. I use this model on on my water haul trailer on construction site to pump water into houses to test for leaks. I often cycle 500 gallons per week. When pumping, the pump rarely gets beyond warm. However, when starting and stopping it will get warmer like in most RV applications. In my case the 3 gallon pressure tank allows it to start and fill the tank then shut off preventing short cycling times and getting hot. Checked all this with my heat gun.... The zip tie loosely holds the carpet pad in place, it is not tightly strapped but seems to make a huge diff in the sound penetration into the coach compartment. The pump in the pix is 10 years old.

Pump in my 98 Itasca lasted until 2016 with exactly this arrangement, we full timed for 6 years during this time.

In fifteen years as a service manager, The pumps I saw overheating were running without pumping water. These pumps were not warm. They were so hot you could feel the heat from a foot away. I am not one of the chicken little " the sky is falling types." I don't try to find fault with everyones ideas. I just think insulating a pump and blocking cooling air is a bad idea. I only posted to keep others from following your advice and possibily having a fire.

[lonfu]

Originally Posted by ga traveler

In fifteen years as a service manager, The pumps I saw overheating were running without pumping water. These pumps were not warm. They were so hot you could feel the heat from a foot away. I am not one of the chicken little " the sky is falling types." I don't try to find fault with everyones ideas. I just think insulating a pump and blocking cooling air is a bad idea. I only posted to keep others from following your advice and possibily having a fire.

Good point, water pumps that run dry will overheat and fail. I completely agree.... and as I pointed out the sound insulation is not attached tightly, the zip tie just keeps it from vibrating off. Got that you have an opposite opinion. My limited experience, 40 years, working on thus stuff just gives me a little different point of view.... BUT....We need Chicken Little's to keep us mechanics in check... No Worries... I won't wrap my diesel in carpet pad to make it quieter...

[lonfu]

Originally Posted by ga traveler

In fifteen years as a service manager, The pumps I saw overheating were running without pumping water. These pumps were not warm. They were so hot you could feel the heat from a foot away. I am not one of the chicken little " the sky is falling types." I don't try to find fault with everyones ideas. I just think insulating a pump and blocking cooling air is a bad idea. I only posted to keep others from following your advice and possibily having a fire.

Ok, you got me to think about......So, since I'm a fan of scientific method and I had to finish sanitizing my system, I decided to test my pump to see if I could get it hot to the touch.... now understand that I didn't need to "feel the heat" from a foot away, just hot to the touch.....

With my cover on:

Ran it dry for 5 mins: Motor 3 degrees hotter than ambient.(max recommended is 2 mins)
Ran it wet no load for 10 mins: motor 1 degree hotter than ambient.
Ran it with against my pressure tank as a full load: no increase in temp.

With out actually wiring this pump incorrectly or intentionally damaging the bearings, I couldn't get this pump to heat up even to warm to the touch... I enlarged my little cover to go over the actual pump on the end too.

I've worked with hydraulics, with loads of 20 tons and more. Some had to have coolers/little radiators on the return fluid lines, but this was some really huge equipment... Not moho levelers.... and the pumps would get hot, often more than hot to the touch...these were huge earth moving machines..... So other than a failed bearing, I can't imagine ever seeing a RV fresh water pump get as hot as you describe. I would imagine with a frozen bearing, they usually just freeze up....

but, if it was plumbed into the hot water tank and or wired to 24 volt source instead of 12v as they are designed for then I can imagine there would be a problem that could cause an issue like you describe. If the operator failed to turn off the pump when running dry for several days then perhaps I could believe that it would get warm, can't do anything about operator error....

I believe the plastic in the actual pump would melt about 200 degrees.

I'm sure you know that Surflo makes a large variety pumps for all kinds of voltages up to 220v and they make air operated pumps too....

Surflo makes one heck of a great RV water pump, I've never had a motor fail, I have had the pump head freeze and crack. Some dummy did pull the filter on the motor.........ME.....Never seen one damaged from heat......

Mine is 10 years old, on at 25 psi off at 45 psi. Pressure tank is set at 26 psi. I could not get it to warm under any ordinary conditions. My little pump cover and the sound dampener base reduces the noise in the coach by at least 60%... I can still hear it, but have to stop moving and the outside noise has to be very low.

I'm glad you caused me to investigate the motor temp thing, I would have been concerned about it while I was using the coach. No one else should be concerned about Surflo RV pumps catching fire.

just so you know.... I don't work for Surflo...

[lonfu]

final pump cover design and wife inspection. Decided to increase the cover to go over the top of the plastic pump head as well as the motor. Cover is still loosely zip tied around motor. Wife says sound inside coach has been reduced by 70%. Says she can't hear the pump with the water in the sink running.

[MarvinG]

I had this problem the first few trips I took in our new to us used Bounder. Coming back from a short weekend trip the smell was overwhelming no matter what I did to mitigate the issue. Installed 360 vent caps on both grey and black vents and the problem completely and immediately disappeared. Two + years later we have NEVER had a recurrence. These little vents are like miracle cures.

[MarvinG]

Ionfu, what noise quieting material did you use for the pump base?

[lonfu]

Originally Posted by MarvinG

Ionfu, what noise quieting material did you use for the pump base?

On my first unit, that is still in use in my 98, I used 2 pieces of 1/2 inch carpet pad. I glued them to the wood and together. Then ran silicon around the outside edge to make sure none of the layers would separate.

ON, version 2, the one you see, I happen to have an old ski vest... you know like for water skiing. Not the orange preserver style but the flat common ski/fishing style. The cover was shredded so I pulled the foam out for small projects. It is some very stout stuff. Gotta be at least 30 years old... I still have the boat, so I know it is old. cut myself some plywood, making the base larger than the pump platform so I could screw it down. I then lightly sanded the plywood and coated it and the foam with some 3m 90 spray glue. The foam is so stout and difficult to tear that I saw no need to coat the edges with silicon like the last one I made in 1998... I mounted drilled the holes in both the base and pump platform before I glued it together.... Glue can be bought at HD or Lowe's.... I can let you know in 20 years if it lasts...

Here is the thing, my "stinky" only occured while parked and when the furnace would cyle on then when it was off I could smell it coming "up" from the furnace vents in the floor. I"d estimate the space around the plumbing pass penetrations totaled at least 12 sq inches. When the furnace would come on, the air forced into the compartment has to go somewhere since there is no outside vent for that compartment. It is forced up around the plumbing penetrations.... I just used my nose to track it down.... Then... when AC was running the cold air would force the hot smelly air down in to the vents. When the AC would turn off I could smell and feel the hot air coming up through the furnace vents from the tank compartment. If I left one of the tank compartment doors open, then, no smell. One time when I was dumping the tanks I could feel cold air dropping from inside the coach around pipe penetrations.

My 2nd moho had the "in motion" stinky problem. So, made a small aluminum box with the back open for a vent cover. I drilled a small hole on the front of the cover so when driving it would use the venturi effect to draw air past the vent and out the back. I was amazed at how well this worked, until the wind when I was parked in just the right direction, would catch the back of my venturi vent... very rare.. but I was young and tough back then and the coach did not have AC so I usually slept with the windows open anyways....

In 1985 I bought my first new coach. I spent 3 months sealing up the floor penetrations and basement. The tank compartment was not heated.

1998 I bought my 2nd new coach, I was pleasantly surprised to find that most of the pipe penetrations had been plugged or sealed. However, I had that stinky smell again. I found that the coach had a vent into the tank compartment and it would back feed in certain conditions into the bathroom. This took me several years because the vent was hidden and I hadn't seen this kind of tank compartment heating..... I solved the problem by sticking a wad of newsprint into the vent where it entered the tank compartment. It allowed hot air into the compartment and prevented back smells..... It is still there and still works... I of course listened to my elders at the time and replaced the toilet and seal. Then checked the vent seals and such on the tanks... All of which, was just a waste of time....

[lonfu]

The good news is that I've solved the inside coach stinky tank problem. But... now when I open my wet bay it smells really bado so I leave it open when I'm home in the garage.... When I come to work in the early mornings guess what greets me when I open the garage door?????

Ok, so not a black water smell, not a gray water smell, because the tanks are empty.... but... a wet bay tank smell... so, since I've plugged all the holes that lead to the interior of the coach, there is no venting in the wet bay compartment.... good.. or so I thought... had to find a way to vent the compartment to the outside of the coach.

One at each end of the compartment...

[radar]

Is it plumbed for washer dryer...and if he doesn’t have one is it capped off properly? There is a vent valve thingy by the pee trap that can get stuck and cause those issues. Happened to us.

[lonfu]

Originally Posted by radar

Is it plumbed for washer dryer...and if he doesn’t have one is it capped off properly? There is a vent valve thingy by the pee trap that can get stuck and cause those issues. Happened to us.

no not plumbed for washer and dryer and I've removed the black water tank flush vacuum valve that you referring to. Most newmars have the tank compartments vent to the interior of the coach by way of the shower p-trap. when the furnace comes on hot air is forced down into the tank compartment and up past the shower p-trap into the coach. Some engineers way of eliminating a exterior vent cost.

[lonfu]

Originally Posted by radar

Is it plumbed for washer dryer...and if he doesn’t have one is it capped off properly? There is a vent valve thingy by the pee trap that can get stuck and cause those issues. Happened to us.

Thought I'd mention, had to remove a lot of the basement plumbing to insulate the pipes. The hot water now stays hot at the faucets due to this insulation. Strange to think a midwest moho manufacturer would build a coach with no pluming insulation.