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Fuel tank cleaning [message #263004] Mon, 29 September 2014 17:18 Go to next message
bpimm is currently offline  bpimm   United States
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Just getting ready to park the coach for the winter as my season is over. We had it out 5 times over the summer and after trip 1 I discovered rusty water in the rear tank, front tank had none that I could drain out but the rear tank had 3-4 gallons of water in it, hard to say exactly how much but I drained a bunch. To get through the season I added a fuel water separator / 12 micron filter thinking that would be enough but apparently the inlet filter on the QJ is finer than 12 microns and on the second outing I only made it 30 miles before it plugged. Fortunately we were still in town and got 3 filters from a parts store and took 2 more to complete the 320 mile round trip. I added a bunch of Neodymium magnets to the bottom of the tanks to try to lock the rust in the tank and that seems to have helped, the last trip was made on 1 filter. Now it's time to drop the tanks and get this problem taken care of, I'm going to replace all the fuel lines while they're out as well and probably add an electric fuel pump as well as fixing the sender in the Aux tank, it always reads full.

Anyone have any suggestions for getting the tanks cleaned out and what about these gas tank sealers that are available, are they any good? I have read mixed results with them and with tanks this size it could be a pain to apply properly. Of course final decisions will be made after the tanks are out and inspected.

The other question I have is where did the water come from?

Thanks for any insight.


Brian & RaeDean 1973 26' #383 Washougal WA

[Updated on: Mon, 29 September 2014 17:19]

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Re: Fuel tank cleaning [message #263005 is a reply to message #263004] Mon, 29 September 2014 17:40 Go to previous messageGo to next message
lotsofspareparts is currently offline  lotsofspareparts   United States
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Can't comment on to much, but can state that the alcohol in modern ethanol fuel will attract water. The best way I know how to get water inside of a steel fuel tank is internal condensation. Seems as though the front tank may get fuel pulled from it more often than the rear tank.

The only way to prevent this type of condensation is to keep the tanks full when parked for extended periods of time.

I fuel up when we get home from a trip.

Jared


Jared & Tina Lazaron + 14yr old Daughter..... 77 Eleganza II "Recherché"..... 73 Canyon Lands 230 "Elephant"
Re: Fuel tank cleaning [message #263015 is a reply to message #263005] Mon, 29 September 2014 18:55 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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lotsofspareparts wrote on Mon, 29 September 2014 17:40
Can't comment on to much, but can state that the alcohol in modern ethanol fuel will attract water. The best way I know how to get water inside of a steel fuel tank is internal condensation. Seems as though the front tank may get fuel pulled from it more often than the rear tank.

The only way to prevent this type of condensation is to keep the tanks full when parked for extended periods of time.

I fuel up when we get home from a trip.

Jared
Rear tank is main and should be the one that fuel is pulled from most of the time. Seems either the tank selector switch is on Aux, or the valve is stuck there. If fuel never gets pulled from a tank, it would take YEARS to accumulate multiple gallons of water, even if the tank was empty AND parked in the South where humidity is high. I had a riding mower that sat for two years with the tank half full and it accumulated a couple tablespoons of water. Enough that it wouldn't start, but easy to remove.

Either it has been accumulating for a long time, or someone poured it in your tank. Remember, when filling, most of the gas flys by the front tank until the rear gets mostly full. It might have got there from a fillup at a station that had water in the underground tank.
Re: Fuel tank cleaning [message #263020 is a reply to message #263015] Mon, 29 September 2014 19:39 Go to previous messageGo to next message
lotsofspareparts is currently offline  lotsofspareparts   United States
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A Hamilto wrote on Mon, 29 September 2014 16:55
lotsofspareparts wrote on Mon, 29 September 2014 17:40
Can't comment on to much, but can state that the alcohol in modern ethanol fuel will attract water. The best way I know how to get water inside of a steel fuel tank is internal condensation. Seems as though the front tank may get fuel pulled from it more often than the rear tank.

The only way to prevent this type of condensation is to keep the tanks full when parked for extended periods of time.

I fuel up when we get home from a trip.

Jared
Rear tank is main and should be the one that fuel is pulled from most of the time. Seems either the tank selector switch is on Aux, or the valve is stuck there. If fuel never gets pulled from a tank, it would take YEARS to accumulate multiple gallons of water, even if the tank was empty AND parked in the South where humidity is high. I had a riding mower that sat for two years with the tank half full and it accumulated a couple tablespoons of water. Enough that it wouldn't start, but easy to remove.

Either it has been accumulating for a long time, or someone poured it in your tank. Remember, when filling, most of the gas flys by the front tank until the rear gets mostly full. It might have got there from a fillup at a station that had water in the underground tank.


The humidity may be high in the south but the PNW sees more swings of the high to low temperatures or low to high than any other region in the lower 48. It is the low to high swing that can bring on the internal condensation I was describing.

Ever seen a toilet tank sweat..... same thing may be going on, inside of your fuel tank.

Jared

Up here it can be 70 degrees, starts raining and then its 50 degrees, or it can be 50 degrees and raining, and then it is 70 degrees and sunny.

He does live in Washougal Washington, he knows what I am trying to say.


Jared & Tina Lazaron + 14yr old Daughter..... 77 Eleganza II "Recherché"..... 73 Canyon Lands 230 "Elephant"

[Updated on: Mon, 29 September 2014 19:44]

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Re: Fuel tank cleaning [message #263036 is a reply to message #263020] Mon, 29 September 2014 21:31 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Yes we do get the temp swings but I still have a problem seeing 3-4 Gallons of water out of the air that is inside the tank. and only 1 of the tanks, I was curious to see if there is a way for rain water to get into the vent line of the rear tank or something like that.

Brian & RaeDean 1973 26' #383 Washougal WA
Re: Fuel tank cleaning [message #263056 is a reply to message #263036] Tue, 30 September 2014 06:45 Go to previous messageGo to next message
lotsofspareparts is currently offline  lotsofspareparts   United States
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bpimm wrote on Mon, 29 September 2014 19:31
Yes we do get the temp swings but I still have a problem seeing 3-4 Gallons of water out of the air that is inside the tank. and only 1 of the tanks, I was curious to see if there is a way for rain water to get into the vent line of the rear tank or something like that.


Anything is possible, I am trying to think of how that could happen and am drawing a blank.

Jared


Jared & Tina Lazaron + 14yr old Daughter..... 77 Eleganza II "Recherché"..... 73 Canyon Lands 230 "Elephant"
Re: [GMCnet] Fuel tank cleaning [message #263057 is a reply to message #263004] Tue, 30 September 2014 07:07 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Brian,

I have read all the responses and noted that no one has answered your first question regarding having the rusty tank cleaned. I
would suggest you Google "Fuel Tank Cleaning, Washougal WA" This should bring up companies near you that can perform that service.

I did that in Houston and found a couple of companies, however, their services were not cheap, I got them to provide a "rough"
estimate after providing the measurements and capacity of the tanks and was told $400 - $500 per tank.

I store my coach in Houston 8 months per year and before I do so I fill the tanks all the way up (adding the correct amount of
Stabil) until I can see fuel in the filler neck at a station about a mile from the storage facility. I drive it back, pull it into
the "garage" and shut it off and don't run it again until the next year when I return. I've been doing this for six years and have
had no problems.

Regards,
Rob M.
The Pedantic Mechanic
USAussie - Downunder
USA '75 Avion - Double Trouble TZE365V100426
AUS '75 Avion - The Blue Streak TZE365V100428

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Brian Pimm
Sent: Monday, September 29, 2014 5:19 PM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Fuel tank cleaning

Just getting ready to park the coach for the winter as my season is over. We had it out 5 times over the summer and after trip 1 I
discovered rusty
water in the rear tank, front tank had none that I could drain out but the rear tank had 3-4 gallons of water in it, hard to say
exactly how much but
I drained a bunch. To get through the season I added a fuel water separator / 12 micron filter thinking that would be enough but
apparently the inlet
filter on the QJ is finer than 12 microns and on the second outing I only made it 30 miles before it plugged. Fortunately we were
still in town and
got 3 filters from a parts store and took 2 more to complete the 320 mile round trip. I added a bunch of Neodymium magnets to the
bottom of the tanks
to try to lock the rust in the tank and that seems to have helped, the last trip was made on 1 filter. Now it's time to drop the
tanks and get this
problem taken care of, I'm going to replace all the fuel lines while they're out as well and probably add an electric fuel pump as
well as fixing the
sender in the Aux tank, it always reads full.

Anyone have any suggestions for getting the tanks cleaned out and what about these gas tank sealers that are available, are they any
good? I have read
mixed results with them and with tanks this size it could be a pain to apply properly. of corse final decisions will be made after
the tanks are out
and inspected.

The other question I have is where did the water come from?

Thanks for any insight.
--
Brian & RaeDean

1973 26' #383

Washougal WA
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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Fuel tank cleaning [message #263061 is a reply to message #263057] Tue, 30 September 2014 09:38 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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USAussie wrote on Tue, 30 September 2014 05:07
Brian,

I have read all the responses and noted that no one has answered your first question regarding having the rusty tank cleaned. I
would suggest you Google "Fuel Tank Cleaning, Washougal WA" This should bring up companies near you that can perform that service.

I did that in Houston and found a couple of companies, however, their services were not cheap, I got them to provide a "rough"
estimate after providing the measurements and capacity of the tanks and was told $400 - $500 per tank.


I did find a place a couple hours away that dips cars and gas tanks. http://www.metaldipping.com
I'll call them and see how much they want to dip the tanks.


USAussie wrote on Tue, 30 September 2014 05:07

I store my coach in Houston 8 months per year and before I do so I fill the tanks all the way up (adding the correct amount of
Stabil) until I can see fuel in the filler neck at a station about a mile from the storage facility. I drive it back, pull it into
the "garage" and shut it off and don't run it again until the next year when I return. I've been doing this for six years and have
had no problems.

Regards,
Rob M.
The Pedantic Mechanic
USAussie - Downunder
USA '75 Avion - Double Trouble TZE365V100426
AUS '75 Avion - The Blue Streak TZE365V100428


That's exactly what I'm planning to do after the tanks are clean, we got the coach last year and the tranny failed so I couldn't fill the tanks but I think the water was already there unless it can get in a vent line or something. We get 90 to 120 inches of rain a year here in the hills NE of Washougal so if it can leak in somewhere there is the potential to fill the tank...


Brian & RaeDean 1973 26' #383 Washougal WA
Re: [GMCnet] Fuel tank cleaning [message #263068 is a reply to message #263061] Tue, 30 September 2014 11:07 Go to previous messageGo to next message
kelvin is currently offline  kelvin   United States
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On 9/30/2014 7:38 AM, Brian Pimm wrote:
> USAussie wrote on Tue, 30 September 2014 05:07
>> Brian,
>>
>> I have read all the responses and noted that no one has answered your first question regarding having the rusty tank cleaned. I
>> would suggest you Google "Fuel Tank Cleaning, Washougal WA" This should bring up companies near you that can perform that service.
>>
>> I did that in Houston and found a couple of companies, however, their services were not cheap, I got them to provide a "rough"
>> estimate after providing the measurements and capacity of the tanks and was told $400 - $500 per tank.
>
> I did find a place a couple hours away that dips cars and gas tanks. http://www.metaldipping.com
> I'll call them and see how much they want to dip the tanks.
>
>
> USAussie wrote on Tue, 30 September 2014 05:07
>> I store my coach in Houston 8 months per year and before I do so I fill the tanks all the way up (adding the correct amount of
>> Stabil) until I can see fuel in the filler neck at a station about a mile from the storage facility. I drive it back, pull it into
>> the "garage" and shut it off and don't run it again until the next year when I return. I've been doing this for six years and have
>> had no problems.
>>
>> Regards,
>> Rob M.
>> The Pedantic Mechanic
>> USAussie - Downunder
>> USA '75 Avion - Double Trouble TZE365V100426
>> AUS '75 Avion - The Blue Streak TZE365V100428
>
> That's exactly what I'm planning to do after the tanks are clean, we got the coach last year and the tranny failed so I couldn't fill the tanks but I
> think the water was already there unless it can get in a vent line or something. We get 90 to 120 inches of rain a year here in the hills NE of
> Washougal so if it can leak in somewhere there is the potential to fill the tank...

My coach has spent it's entire life in Oregon. I don't know that we get
the heavy rain that Washington does but we get plenty of it. My tanks
were pristine when I pulled them in 2007. I can't imagine there's a way
for water to get into the tanks thru the OEM vents and such. I don't
always keep the tanks filled up during the camping season but do top
them up when it gets parked for any length of time in the winter. 12
years in my hands and no problems with water in the fuel that I can tell.

Get the tanks repaired, keep them full and you should have no issues.

Then again, some PO might have done something whacky. That happens, too...

Kelvin
'73 23' in Eugene, OR
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Re: [GMCnet] Fuel tank cleaning [message #263071 is a reply to message #263068] Tue, 30 September 2014 13:05 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Kelvin Dietz wrote on Tue, 30 September 2014 09:07


Then again, some PO might have done something whacky. That happens, too...

Kelvin
'73 23' in Eugene, OR


That's one of my concerns, so far there has been a lot of that with this coach...


Brian & RaeDean 1973 26' #383 Washougal WA
Re: Fuel tank cleaning [message #263079 is a reply to message #263004] Tue, 30 September 2014 16:03 Go to previous messageGo to next message
Tony Cook is currently offline  Tony Cook   United States
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I to am dealing with this well not the water issue i think ? When i got my '77 it had been sitting for 7 years there was no fuel in the tanks just fine orange rust dust hoping the clear glass inline filter i added will help remove over time cause yea the Qj filter gets clogged real quick and seems easier to get to the added filter for cleaning. Is it possible or should i say safe to remove the fuel line and intall a bigger inline filter maybe like a pool filter LOL ! and pump it back into the gas tank fill and letting the gas recirculate and filter ? Just dont want to have to drop the tanks ....yet

Tony Cook 77' Kingsley ' SuperSession 77 ' Torrance Beach,CA
Re: Fuel tank cleaning [message #263081 is a reply to message #263004] Tue, 30 September 2014 17:12 Go to previous messageGo to next message
Tony Cook is currently offline  Tony Cook   United States
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BTW my tank plugs are not budging

Tony Cook 77' Kingsley ' SuperSession 77 ' Torrance Beach,CA
Re: [GMCnet] Fuel tank cleaning [message #263082 is a reply to message #263081] Tue, 30 September 2014 17:30 Go to previous messageGo to next message
kelvin is currently offline  kelvin   United States
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On 9/30/2014 3:12 PM, Tony Cook wrote:
> BTW my tank plugs are not budging

Buy a cheap electric pump, disconnect the fuel line at some point (I do
it next to the transmission on the frame rail) and empty your tanks with
the pump. Pulling that plug is scary to me. If there's more fuel than
you expected how do you stop the flow? Putting the plug back in is a
lot messier than disconnecting a wire to stop the pump.

And yes, I'd be careful of that "spark" while connecting and
disconnecting the pump. I actually have a switch wired into the ground
wire of the pump.

Kelvin
'73 23' in Eugene, OR
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Re: Fuel tank cleaning [message #263083 is a reply to message #263081] Tue, 30 September 2014 17:52 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Mine didn't want to come out either, what I did was to use a 3/8 drive allen bit in my 1/2 drive electric impact and they came out. putting the plug back in while it's flowing is a bit messy. I went through 10 cycles draining into a 1 Gal ice cream tub before I got the water out. I expect to find more when I pull the tanks because the drain is not in the lowest part of the tank.

Brian & RaeDean 1973 26' #383 Washougal WA
Re: Fuel tank cleaning [message #263084 is a reply to message #263083] Tue, 30 September 2014 18:21 Go to previous messageGo to next message
Loffen is currently offline  Loffen   Norway
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To clean it you can use some grawel or nuts and bolts together with a strong vinegar and hot water mix, just put neverything in the tank and shake.

1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green, And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel in Norway
Re: [GMCnet] Fuel tank cleaning [message #263085 is a reply to message #263081] Tue, 30 September 2014 19:55 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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When I tried to get mine out the hex inside stripped.
I then tried a small pipe wrench on the outside of the threads and they came out easily.

Emery Stora
77 Kingsley
Frederick, CO

On Sep 30, 2014, at 5:12 PM, Tony Cook wrote:

> BTW my tank plugs are not budging
> --
> Tony Cook
> 77 Kingsley 26'"SuperSession77"
> Torrance Beach,CA
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Re: Fuel tank cleaning [message #263089 is a reply to message #263004] Tue, 30 September 2014 21:46 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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I used my electric fuel pump to empty my tanks this summer. I pulled my pickup next to the GMC and put a long piece of fuel line from the pump to my pickup tank which was nearly empty. It did not take long before I was getting air out of the pump. If I was concerned about getting water, I'd pump into a transparent container and watch for the separation. No separation, I'd filter it and use it in something unless it was bad.

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: [GMCnet] Fuel tank cleaning [message #263092 is a reply to message #263082] Tue, 30 September 2014 22:21 Go to previous messageGo to next message
Joe Weir is currently offline  Joe Weir   United States
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Kelvin Dietz wrote on Tue, 30 September 2014 17:30
On 9/30/2014 3:12 PM, Tony Cook wrote:
> BTW my tank plugs are not budging


And yes, I'd be careful of that "spark" while connecting and
disconnecting the pump. I actually have a switch wired into the ground
wire of the pump.

Kelvin


Buy a cheap 12v switch. Install switch in one of the wires, away from the pump, but close to the container you are pumping into so you can shutoff when needed.


76 Birchaven - "Wicked Mistress" - New engine, trans, alum radiator, brakes, Sully airbags, fuel lines, seats, adult beverage center... those Coachmen guys were really thinking about us second hand owners by including that beverage center... Columbia, SC.
Re: Fuel tank cleaning [message #263124 is a reply to message #263036] Wed, 01 October 2014 18:57 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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bpimm wrote on Mon, 29 September 2014 21:31
Yes we do get the temp swings but I still have a problem seeing 3-4 Gallons of water out of the air that is inside the tank. and only 1 of the tanks, I was curious to see if there is a way for rain water to get into the vent line of the rear tank or something like that.


Mice

http://www.gmcmhphotos.com/photos/getting-started/p24746-getting-started.html


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Fuel tank cleaning [message #263135 is a reply to message #263084] Wed, 01 October 2014 22:41 Go to previous messageGo to previous message
Adrien G. is currently offline  Adrien G.   United States
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Loffen wrote on Tue, 30 September 2014 18:21
To clean it you can use some grawel or nuts and bolts together with a strong vinegar and hot water mix, just put neverything in the tank and shake.



Loffen,

It's not that easy. The tanks have 2 baffles dividing the tank in 3 parts (center section, a left and a right section.
The corner opening on the baffles are not very large.

I've wander how a person would make sure that the tank sealer coated everywhere on the not visible baffled section.

Just thinking.





Adrien & Jenny Genesoto 75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
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