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Topic: Cleaning the INSIDE of RV Propane tank (Read 873 times) previous topic - next topic

Cleaning the INSIDE of RV Propane tank

I rebuilt the Regulator on my Onan 6.5k Genny. changed it over to the gas side of the tank and I'm still getting the Genny stopping after a short amount of time (30min) and under load even faster. Have changed all the filters at this point. May need to blow out the feed line but I want to clean the inside of the tank as well but I have not been able to find anyone that does that work. Any ideas from the Brain Trust?
Thx
1995 U-240 GrandVilla 36'
FMC# 18675
Lookingglass, OR
"There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." - Ed Howdershelt Abintra Press "If you have to lie to gain Support, you are not worth Supporting" "I just want to go somewhere where there's chocolate and nobody talks." - Ynez Reinschmidt

Re: Cleaning the INSIDE of RV Propane tank

Reply #1 –
If you have changed the generator propane feed to HIGH PRESSURE VAPOR (T off the vapor port before the house regulator), no need to do anything.

The longer hydrocarbon contaminants don't vaporize at "normal" temperatures, so far less contamination.

Many of us have done this after overhauling/replacing the on-generator regulator and finding it clogged with a light viscosity grease.

BTW, this suggestion came from an engineer at Marshall Gas who made lots of RV propane regulators.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Cleaning the INSIDE of RV Propane tank

Reply #2 –
Not an expert on propane generators. Do they have carburetors, which has all the same issues as a gasoline generator.

Are you flowing liquid propane (near bottom of tank), high pressure propane gas (directly from upper 20% of tank before main tank regulator), or low-pressure gas (from after the main tank regulator).

May help to use a propane pressure gauge be sure the gen is being supplied the correct low-pressure gas.

Is the main propane tank full to 80% spit valve.

A propane dealer, especially a small one may be able to help debug it.

Re: Cleaning the INSIDE of RV Propane tank

Reply #3 –
Ran some on the liquid side then Switched over to the High pressure vapor (before the regulator) and it still got stuff in the regulator. :( rebuilding the regulator again.


1995 U-240 GrandVilla 36'
FMC# 18675
Lookingglass, OR
"There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." - Ed Howdershelt Abintra Press "If you have to lie to gain Support, you are not worth Supporting" "I just want to go somewhere where there's chocolate and nobody talks." - Ynez Reinschmidt

Re: Cleaning the INSIDE of RV Propane tank

Reply #4 –
If like the 1993 U240's propane generator, from the factory, it used the liquid LP tap.  The on-generator regulator is laying on its side, so contaminants accumulate rather than just passing through/being burned as they would be were the regulator oriented vertically (very widely used regulator for vehicles where it IS installed vertically.

Easy to change to high pressure vapor.  Doubt low pressure vapor (11 column inches water) would work.

If this is not how the 1995 is plumbed, please let us know.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Cleaning the INSIDE of RV Propane tank

Reply #5 –
Quote from: Cpt_kludge –
Ran some on the liquid side then Switched over to the High pressure vapor (before the regulator) and it still got stuff in the regulator. :( rebuilding the regulator again.

Shut off the vapor port (which is not supplying the generator as well as house.  Start the generator and let it run out of fuel.

Remove the line at tank as well as at generator regulator (when you remove the regulator to clean it).  Use compressed air to blow out the line.  Certainly, liquid contaminants could have remained in the line from when it was operating on liquid.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Cleaning the INSIDE of RV Propane tank

Reply #6 –
Quote from: Cpt_kludge –
I rebuilt the Regulator on my Onan 6.5k Genny. changed it over to the gas side of the tank and I'm still getting the Genny stopping after a short amount of time (30min) and under load even faster. Have changed all the filters at this point. May need to blow out the feed line but I want to clean the inside of the tank as well but I have not been able to find anyone that does that work. Any ideas from the Brain Trust?
Thx
Any shop that can recertify portable tanks can do it. They simply drain and remove valve or larger plug. Visually inspect for corrosion then restamp. If you do have it recertfied ( although not required) for a permanently mounted tank have them replace the rubber seals in the tank valve seat. Its like a six dollar upcharge
Scott

Re: Cleaning the INSIDE of RV Propane tank

Reply #7 –
Quote from: wolfe10 –
If like the 1993 U240's propane generator, from the factory, it used the liquid LP tap.  The on-generator regulator is laying on its side, so contaminants accumulate rather than just passing through/being burned as they would be were the regulator oriented vertically (very widely used regulator for vehicles where it IS installed vertically.

Easy to change to high pressure vapor.  Doubt low pressure vapor (11 column inches water) would work.

If this is not how the 1995 is plumbed, please let us know.
Here is the drawing from the Onan manual. It matches my setup.  The Regulator is noted as shown with the connections on the top and the reg mounted vertically.
1995 U-240 GrandVilla 36'
FMC# 18675
Lookingglass, OR
"There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." - Ed Howdershelt Abintra Press "If you have to lie to gain Support, you are not worth Supporting" "I just want to go somewhere where there's chocolate and nobody talks." - Ynez Reinschmidt

Re: Cleaning the INSIDE of RV Propane tank

Reply #8 –
Quote from: dsd –
Any shop that can recertify portable tanks can do it. They simply drain and remove valve or larger plug. Visually inspect for corrosion then restamp. If you do have it recertfied ( although not required) for a permanently mounted tank have them replace the rubber seals in the tank valve seat. Its like a six dollar upcharge
Scott
First I have to find someone that will even WORK on the tank. The local propane dealers do recert REMOVABLE tanks but not fixed RV tanks. The three RV places here in town (one I know well) have never heard of actually CLEANING a Fixed RV Propane tank! The place doing the work now, Oregon Motorcoach (certified Foretravel)Has never heard of cleaning the tank. I will tell them to blow out the line and make sure it is connected to the HP vapor side. I set up the HP Vapor side with a valve so it only needs to be moved from the liquid side.
1995 U-240 GrandVilla 36'
FMC# 18675
Lookingglass, OR
"There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." - Ed Howdershelt Abintra Press "If you have to lie to gain Support, you are not worth Supporting" "I just want to go somewhere where there's chocolate and nobody talks." - Ynez Reinschmidt

Re: Cleaning the INSIDE of RV Propane tank

Reply #9 –
Quote from: Cpt_kludge –
I set up the HP Vapor side with a valve so it only needs to be moved from the liquid side.

I am confused.  From post #3 I assumed most of the run time since regulator overhaul was on high pressure vapor.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Cleaning the INSIDE of RV Propane tank

Reply #10 –
Quote from: Cpt_kludge –
I rebuilt the Regulator on my Onan 6.5k Genny. changed it over to the gas side of the tank and I'm still getting the Genny stopping after a short amount of time (30min) and under load even faster. Have changed all the filters at this point. May need to blow out the feed line but I want to clean the inside of the tank as well but I have not been able to find anyone that does that work. Any ideas from the Brain Trust?
Thx
Yes.  Don't tell the propane company that you're doing this.
The tank needs to be purged of air after you're done and your choices here are CO2* or vacuum.  New Manchester cylinders and tanks are *I believe* shipped empty: no air.
The tank contains an amount of alcohol to gather up the accumulated water.
Do the reading on best solvent then triple rinse with that solvent.

Listed in order of importance.
* Three squirt and release, then call the propane company and tell them you need propane.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Cleaning the INSIDE of RV Propane tank

Reply #11 –
Quote from: wolfe10 –
I am confused.  From post #3 I assumed most of the run time since regulator overhaul was on high pressure vapor.

Most of the time was on HP Vapor. Some after I rebuilt it and before I got the parts to change over was on Liquid. I did not blow out the hose to the Genny. It started running for a while then shutting off under load while connected to the HP Vapor. I switched it back to Liquid to see if that fixed it. Of course, it didnt.. The mechanic has replaced all the filters and is rebuilding the regulator(again). I just left a msg with the mechanic to blow out the line and reconnect to the HP Vapor output!
1995 U-240 GrandVilla 36'
FMC# 18675
Lookingglass, OR
"There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." - Ed Howdershelt Abintra Press "If you have to lie to gain Support, you are not worth Supporting" "I just want to go somewhere where there's chocolate and nobody talks." - Ynez Reinschmidt