Horizontal ASME Propane Tank Refurbishing Questions

[AtlantaCamper]

I have a horizontal mounted propane tank that needs some attention.    All of the valves and fittings are original from 1988 I believe.  The fill valve started leaking a tiny bit based on a soap bubble test after it was filled it the other day. The service valve seals when all the way in and out but leaks a bit when opening/closing.  I am planning to use the rest of the propane in the tank, then disconnect the tank at the regulator to service valve connection, removing the tank from the vehicle and then refurbishing it.  

The refurb would involve replacing the fill valve, the service valve and the regulator.  The bleed port and float gauge seem to be working ok so I might as well leave them alone.
There are square flange fittings that have some sort of gasket holding the threaded inlet ports to the tank.  I am planning to leave these alone rather than trying to take them apart and replace the seal.  
I will clean the tank and re-paint. There is only minor rust and the tank appears to be in good overall condition despite the grime. I’ll use the proper yellow teflon tape to put the new fittings in.  I’ll get the regulator from Lowes per Fred’s suggestion and the other valves from PropaneWarehouse.  I think these are the appropriate parts:

• Fill Valve:  INLET 1-3/4" ACME, OUTLET 3/4" MNPT, MFG PART NUMBER 1855SD
• Service valve:  ASME Valve with Relief, INLET 3/4" MNPT, OUTLET Female POL (CGA510), MFG PART NUMBER 3250BC312

The tank is not the removable DOT kind, it is the stationary ASME and so it apparently doesn’t need to be recertified.  I often have found that the U-Haul tech filling my tank will look for or ask what the certification date is.  Usually they just fill it after I tell them this is an ASME tank and doesn’t need recertification, but once they refused to fill it and I had to go somewhere else.  Am I correct that I do not need to have it recertified?  What about purging/leak testing and fill?  Should I get it all done and put it back on the truck and then take it to Amerigas or a similar place to have it purged and filled and then do a leak test with soapy water?  

If anyone has suggestions about how I should be doing this job I would appreciate the input as this is my first propane tank refurb.
 

[linda s]

This is a very long thread but details another member replacing propane valves on a Sunrader propane tank.

I don't know enough about it to pick and choose what you might need so I'm giving you the whole thing.

It sounds like he had his leak tested when he took it in to get purged. First time leaked like a sieve and

he had to go back and fix some stuff. I also think he had his purged before he installed it. 

Stock Horizontal Propane Tank Filling Problem - Fuel Tanks - Toyota Motorhome Discussion Board

Linda S

[AtlantaCamper]

Thanks for that Linda.  A lot of useful info there.  Hopefully I won't have as much trouble with leaks... 

 

I've been calling all the propane companies around Atlanta and I can't find anyone that will do a purge and/or leak test on a tank like this.  Camping World said no too.    Hopefully I can find a place to do the proper test and fill once the refurb is done.

[fred heath]

Most propane dealers won’t touch your tank due to liability issues.

 

I did basically the same thing you’re planning to do.

 

Replace everything needed. Try to find an equipment rental yard that uses propane. They should have a propane filling station. Many times it’s easier to get serviced at a place like that than a regular dealer.

 

As far as the purging, I don’t believe I ever had to do that. I just put about 1 gallon in the tank and ran my gas appliances until the flames were uniform. Didn’t take much propane to do that. Then refilled the tank to full.

 

You could also ask the person filling the tank to do a purge. Some will, some won’t.

 

If your tank looks all pretty and new you will find it’s much easier to get service.

Edited August 15, 2023 by fred heath

[Odyssey 4x4]

I completely refurbished my tank on the Odyssey. I pulled it off, drained it completely, removed all valves and gauges, sanded the entire thing down, and repainted it. I then took it to a local propane place and was lucky enough to have a kind old gentleman that took a look at the inside of it with a camera and was happy with the condition. He then installed all new valves for me and slapped a brand new certification sticker on it and filled it up! 

 

 

[linda s]

Well Odyssey 4x4 is in Florida. Atlantacamper maybe it would be worth the drive. The finding the old guy is the key.

I was going to have some valves replaced in mine to just upgrade them and Suburban propane said no problem. 

By the time I got around to it, Bennie, the only guy that new how to do it had retired and they had no one else that would 

even try. Still got old valves. 

Linda S

Possible place to go. They service forklifts and food trucks. Most food trucks use ASME tanks

Commercial Propane & Forklift Cylinders | Metro Atlanta | Georgia Gas

[AtlantaCamper]

Thanks for the tips y'all.  While I'm looking for a place to do the leak test and purge I'm going to go ahead and get started with the tank refurb.  I've ordered the new valves and I'll get the tank off the rig now.

 

The only 'service' I'll need is to leak check and purge.  There isn't any need to certify my type of tank.  I'll keep trying to find the right person at the right place (good idea on that place Linda). 

[AtlantaCamper]

It seems I have an odd fill port size.  Standard sized are 3/4" NPT or 1 1/4" NPT into the tank.   Mine measures 1.2" OD (with calipers, not the ruler), which seems to be 1" NPT according to https://www.ultimatewasher.com/dimensionschart.htm:

This is a 1987 tank, all original parts.  The service valve (with integral relief) seems to be normal size at 3/4" NPT.  For the fill I'm thinking of just using the standard 3/4" NPT part from Propane Warehouse with a 3/4" to 1" NPT adapter like this:

If anyone thinks this is a poor choice or has insight into this NPT fitting size issue for the fill valve I'm all ears.  As long as I don't have leaks it should be ok.  I've not found a Fill valve with 1" NPT.

The tank itself is pretty dirty but I think it will clean up ok.  Issue now is that it's 3/4 full.  I have it hooked up to a turkey fryer burner to get rid of the propane.  Might take well over 24h to burn off at the rate it's going....

I'm also realizing it's going to be difficult to get a wrench into that confined space to get the valves on/off....

[fred heath]

There should be a metal build plate attached to the tank somewhere. That will give you the manufacturer’s name and tank size. Most RV tanks are made by Manchester Tank. You may have to scrape some of the crap off the tank to find the plate.

 

You can contact the manufacturer directly for correct part numbers. If no longer in business, an online search should provide some answers.

 

Propane warehouse might also be able to help.

 

It might make more sense to try and find a garage or business that does sandblasting. It will take you forever doing it by hand. IMHO

[linda s]

It's a Sunrader. His tank is a Manchester 6815. They haven't made that size for a while. Most new tanks are lower fill because vans are more popular. I must admit I have never seen that huge guard on any I have ever looked at. Usually just a guard at the bottom to protect the valves from road debris. Strange

Linda S 

[extech]

propane dealers have special tools to remove the valves. my buddy took lots of them out to use the old tanks for other purposes 

[AtlantaCamper]

14 hours ago, linda s said:

I have never seen that huge guard on any

Yea, it's big and in the way.  I had to really wangle it around to get it out through the bottom of the rig.

 

In order to empty the tank I'm burning off the propane with a turkey fryer burner.  Slow but effective.  In the last 16 hours I've burned off about 30% to 40% of what's left.  Still a while to go though...    

 

16 hours ago, fred heath said:

Propane warehouse might also be able to help.

I've contacted them but no answer yet regarding my seemingly odd fill valve inlet size.  Once it is empty and I can take the old valve off and inspect the mounting flange I may get more info on this NPT inlet thread size issue.

12 hours ago, extech said:

propane dealers have special tools to remove the valves

Excellent suggestion!  I looked up the tool and then fashioned one myself from a part I found in the garage.  It was just strong enough to move the valve so I think it will solve this issue of getting the service valve off/on.  The old fill valve has two flats on it for a wrench and I think I have just enough access around that big metal guard to get that off and the new one has six hex flats so getting the new one on should be fine too.  I'll have more room to work on that once the service valve is out too.  Here's my DIY tool:

[AtlantaCamper]

All is going well and the tank is ready to re-install in the camper.

It took a full 48 hours to burn off the propane in the tank.  I cleaned it up and did a primer/topcoat and then took the valves out and installed the new ones.  I pressure tested by connecting an air compressor to the service valve with some brass fittings and pressurized to 100 PSI and did a bubble leak test.  No leaks were observed.  NOTE: I used DRY air to do this by running the compressed air through molecular sieves to remove the water.  Otherwise you are going to get water in the propane tank doing this step in the same way that you get water collecting in the air compressor tank.  In the humid South a lot of water comes out of the air when compressed.  I'm confident I didn't introduce water.  I then purged the tank with propane gas from a portable cylinder by injecting low pressure  propane into the service port and then venting with the bleed valve.  I did this purge cycle six times so I have only low pressure LP in the tank now.  I can now install the tank, new regulator and new soft hose and then go fill it up.

 

With regard to the odd 1" NPT fill port mentioned previously, it turns out that the fill port from 1987 was an odd two piece fitting with a standard 3/4" NPT into the tank flange but two halves that have a 1" NPT threads.  The new fill valve is shorter so I hope there isn't an issue connecting when it's time to fill.  Here is the new/old valve:

 

For reference, here is the tag on the tank once the grime was removed:

 

It's 10.2 gallons.  When it says 1/4 full and time to fill there is still about 2.5 to 3 gallons left.  I typically get about 4.5 to 5 gallons into it at a fill, which would then be a total of about 7.5 to 8 gallons at the 'full' mark, which is right near the spec of 80% propane = max full.

 

The tank was not too bad under the grime. I used 60 grit sandpaper by hand to get corners but mostly flap disc sander on a grinder to remove the paint/rust.  Took about 3 hrs total for the prep.  Here is the tank just before painting:

 

Here is the tank hanging where I painted it and it's drying and still getting the last of the propane out with the turkey fryer.  This is quite the redneck setup:

 

I painted with the old valves on, then took them off and put the new ones in.  I used a big 1-3/4" socket for the fill valve and that tool I made to put the service valve in.   I wrapped the thick yellow PTFE tape 4 rounds over the blue sealant as propane warehouse recommended. Bleed pot and fill gauge were left as they were.   Here are the valves:

 

I'll give a final update once I have it reinstalled with a new regulator and soft line and filled. 

 

Edited August 19, 2023 by AtlantaCamper

[linda s]

Wow, incredible job. Your tank is from a company I've never heard of. I have looked at so many Sunraders and I've never seen one with anything but a Manchester tank. That explains the big guard on it. On the good side you have a larger propane capacity than all the other Sunraders. They all came with a 7.9 gallon tank no matter what the size of the rig. 

Linda S

[AtlantaCamper]

I got it mounted and then got a UHaul place to put 6 gallons in it and all is well.  No leaks, all seems fine.  And once the air in the line from opening it up was purged out the stove it burns clean and blue.  With the new regulator I think I have a tad more pressure than the 1987 one.  it runs my stove better and with more consistent variation in flame with the dial.

Edited August 19, 2023 by AtlantaCamper

[AtlantaCamper]

DOT vs ASME fill stations and "fill to auto-stop" vs "add XX gallons" strategy for filling:

 

At the U-Haul today they had two different filling systems.  One was for DOT tanks and it fills slower and has this kind of nozzle plus various adapters:

The other system is for ASME tanks and has this nozzle for the 1-3/4″ Acme threads:

The ASME filler fills FAST (ASME tanks are usually large and DOT are relatively small) and it could fill my entire tank in in like 20 or 30 seconds.  This concerned me a little because I'm not sure how sensitive or accurate my OPD (Overfill Protection Device) is.  My strategy with these "fast fill" systems is to ask to put a specific amount in rather than going to "full".  An overfull tank is not a good idea I'm told (too much pressure, possible damage to regulator).  The tech said they are told to not use the vent valve.  They will NOT fill my tank with the vent open to see liquid come out if the OPD fails to shut off the flow.  

 

Using the ASME pump I had the tech stop filling from empty at 3 gallons and then pause (reading was exactly at the "1/4" full mark on the gauge), and than at 5.1 gallons  and pause to let the gauge settle (pretty much right at 1/2 on the gauge) and so I feel pretty confident now of the gauge readings at these two points.  (5.1 is half of the 10.2 gallon capacity of my tank).  Normally I run it down to 1/4 on the gauge and then have it filled.  Fills to 80% are always right at 4.5 to 5 gallons this way.  

 

My original tank had this sticker on it:

I'm not going to put it on the newly refurbed tank because nobody seems to pay attention to it anymore.  Everyone's training says to not open the bleed valve. The fancy ACME filler is supposed to have an auto recovery system for the propane like a regular gasoline pump.  They don't want any extra propane getting out so no venting, certainly no liquid coming out (I noticed there was _zero_ propane smell during the entire fill process so i guess that system actually works).  So fine, if that's the way they want to do it I'm just going to go with the "put 5 gallons in" method when it's at the 1/4 mark and this puts me right at 80% full.  I can monitor the fill with the slower DOT pumps to tell them to stop near the full line, but the ACME filler is so fast that the gauge isn't accurate during fill because so much liquid is sloshing around in there.  Either way I'm just not all that comfortable relying on the system to automatically shut off at 80%  Anyone have any advise on this issue?  Am I being over-cautious?  If anyone has more insight on tank filling please let me know or correct any errors I have in this post.

[linda s]

I have never seen an ASME nozzle like that before. I suggest you reprint your label because when traveling it's very possible the places you stop for propane might not have seen a nozzle like that either. 

Linda S

[AtlantaCamper]

2 hours ago, linda s said:

I have never seen an ASME nozzle like that before

Perhaps it is a U-Haul thing?  I've seen them at several local U-Haul fill sites.  I assumed those are the normal thing for fast fill of the larger ASME tanks.  In central Atlanta U-Haul is pretty much my only option for propane fill locally.  It would be interesting to know if that fill nozzle is uncommon. 

 

I saved that label by carefully removing it and I have some adhesive that could put it right back where it was.  I'm still on the fence about putting it back or not.

[linda s]

Last time I had my tank filled it was at a TA truck stop. Huge chain with 300 truck stops nationwide. No such nozzle there. It's not like the standard nozzles take that long to fill a tank. Couldn't find anything about that nozzle either but just did. It's a quick connect for refilling propane vehicles like buses. Maybe U-Haul Atlanta has the contract to fill city busses there and that's why they all have them. Don't think it's going to be that likely you will find them at service stations on the road. Expensive equipment.

Linda S

[fred heath]

I’ve never seen that quick fill setup while traveling. Always the first style shown.

 

I do carry an ACME 1 3/4” adapter (fits my tank) in the event I stop somewhere that doesn’t have that  particular adapter available.

Edited August 20, 2023 by fred heath

[AtlantaCamper]

5 hours ago, fred heath said:

I’ve never seen that quick fill setup while traveling.

It sounds like the setup I run into at the Atlanta UHauls is more of an anomaly and so this is really a non-issue. 

 

5 hours ago, fred heath said:

I do carry an ACME 1 3/4” adapter

I can see that being useful in some situations. 

[linda s]

Truth is if someone with a conventional nozzle needed to read that label to know how to do it I wouldn't want them filling my tank anyway

Linda S