Gas tank replacement/upgrade

[Arthur138]

My motorhome has been sitting for about 5 years,and rather than try to clean out the old gas tank and coat it for ethanol use,I'm thinking I would rather replace it with a poly or aluminum tank to prevent rust in the future.

Class A motorhome and I THINK the tank in it now holds around 100 gallons of gas.

It is a 1984 Southwind 30 footer with a 454 Chevy engine,turbo 400 transmission,and IIRC,is built on a GM P-30 chassis

Anyone have any recommendations?

[Bill_Satellite]

Arthur138 wrote:

Jim Norman wrote:
If you are doing a conversion to ethanol you will need to do a lot more than just the tank. All the seals and fuel lines can be affected. On top of that Ethanol gives less power per unit and lower MPG. From your second post I am lead to believe that you have done similar on other vehicles so please don't take this wrong. I don't get why you'd want to switch over to Ethanol or even E85. E10 is bad enough!!

EVERYBODY is switching over to ethanol because that is all you can buy at the pumps these days.

And make no mistake about it,even 10 percent ethanol will eat old non-ethanol rated rubber gas lines,and plastic gas filters like acid. There has been people die from rotten gas lines bursting as they were riding down the road at 60 MPH because they were burned to death before they could get their cars stopped.

And you can't replace just the hoses and hope to get away with it. You have to replace it all.

I will even replace the hard lines with the new copper-nickel lines that you can bend by hand without kinking. I do this to prevent rust from developing inside the steel lines and causing carb problems like flooding or backfiring. BTW,in case you don't know,you can buy the copper-nickel lines in any auto parts store in the country. Costs about 25 bucks plus taxes for a 25 foot long roll. Cheap insurance,in MY mind.

10% ethanol will NOT have any effect what-so-ever on older gas engines or their associated fuel lines. If that's what you are concerned about then you are simply baying at the moon and should just fill up your tank and head for the nearest campground where you can setup and worry about important things like "did the US fact the Moon landing!"

[Arthur138]

chuckftboy wrote:
You probably would have better luck with having an aluminum tank fabricated since most custom tank shops can manufacture to your old tank specifications making the install much easier using the original mounting and fuel line
locations.

Thanks. I was hoping to find someone with the same RV that had already had it done so I could just go ahead and buy one without having to make patterns and send them off and wait weeks to get a tank back.

[Arthur138]

Jim Norman wrote:
If you are doing a conversion to ethanol you will need to do a lot more than just the tank. All the seals and fuel lines can be affected. On top of that Ethanol gives less power per unit and lower MPG. From your second post I am lead to believe that you have done similar on other vehicles so please don't take this wrong. I don't get why you'd want to switch over to Ethanol or even E85. E10 is bad enough!!

EVERYBODY is switching over to ethanol because that is all you can buy at the pumps these days.

And make no mistake about it,even 10 percent ethanol will eat old non-ethanol rated rubber gas lines,and plastic gas filters like acid. There has been people die from rotten gas lines bursting as they were riding down the road at 60 MPH because they were burned to death before they could get their cars stopped.

And you can't replace just the hoses and hope to get away with it. You have to replace it all.

I will even replace the hard lines with the new copper-nickel lines that you can bend by hand without kinking. I do this to prevent rust from developing inside the steel lines and causing carb problems like flooding or backfiring. BTW,in case you don't know,you can buy the copper-nickel lines in any auto parts store in the country. Costs about 25 bucks plus taxes for a 25 foot long roll. Cheap insurance,in MY mind.

[chuckftboy]

You probably would have better luck with having an aluminum tank fabricated since most custom tank shops can manufacture to your old tank specifications making the install much easier using the original mounting and fuel line
locations.

[Jim_Norman]

If you are doing a conversion to ethanol you will need to do a lot more than just the tank. All the seals and fuel lines can be affected. On top of that Ethanol gives less power per unit and lower MPG. From your second post I am lead to believe that you have done similar on other vehicles so please don't take this wrong. I don't get why you'd want to switch over to Ethanol or even E85. E10 is bad enough!!

[RLS7201]

Bill.Satellite wrote:
100 gallons would be on the smallish side for most diesel coaches and not at all unusual on a gas coach. He also mentions a conversion to ethanol which I can't imagine being done on a diesel engine.
I've been wrong before, however!

Pre fuel injected class a gas coaches did have 100 gallon fuel tanks.
Post fuel injected class a gas coaches have 75-80 gallon tanks.

Richard

[ksg5000]

Everyone has a different sized wallet - but if it were me I would drain the fuel tank, change the fuel filters, and see what happens. Five years sitting in my area of the country wouldn't mean you had to buy a new fuel tank ... don't know whether my experience applies to your area/situation. What I do suspect - a new fuel tank isn't going to add one penny to the resale value of a 84 rig.

[TNGW1500SE]

How much gas is in the tank and what are you going to do with it?

If there isn't much fuel in it, I might just add fresh gas and burn it through the engine. After that I'd replace the filter.

[Arthur138]

rgatijnet1 wrote:
You don't give much information but at 100 gallons, I might guess that it is a diesel engine. I don't know of any gas coaches that had a 100 gallon tank. Not saying there aren't some out there but I have never heard of them. I know you said ethanol use but just checking.

Sorry. I have now edited my post to include the fact it is a 1984 Southwind with the 454 gm engine and turbo 400 trans,and it's on a P-30 GM chassis.

[Arthur138]

crasster wrote:
I'd inspect before I replaced, but to each their own. May be a perfectly fine tank. If the tank doesn't have rust and if it were me I'd just siphon the gas, add fresh gas, marvel mystery oil in the gas, and a bit of marvel mystery oil to the oil. May be worth adding a drip of oil down each spark plug hole (when the engine starts it WILL smoke), but this is to lubricate the cylinder a bit.

It's been sitting at least 5 years,and was rarely used before I bought it. I can practically guarantee you that it is rusty inside,and I have never had any luck with gas tank sealers or coatings holding up to ethanol. Taking that tank out,cleaning it,coating it,and putting it back in there and then getting broke down on the road due to clogged fuel lines/filter/carb and having to be towed to a repair garage can be pretty expensive. I'd rather spend the money up front and not get stuck somewhere on the side of the road away from home.

I am already planning on replacing all the gas lines and fuel filters with ones rated to handle ethanol. I even did this with my 51 Ford coupe.

[Bill_Satellite]

100 gallons would be on the smallish side for most diesel coaches and not at all unusual on a gas coach. He also mentions a conversion to ethanol which I can't imagine being done on a diesel engine.
I've been wrong before, however!

[rgatijnet1]

You don't give much information but at 100 gallons, I might guess that it is a diesel engine. I don't know of any gas coaches that had a 100 gallon tank. Not saying there aren't some out there but I have never heard of them. I know you said ethanol use but just checking.
If it is diesel, I'd drain the tank and just try new diesel with an additive to kill any fungus. You may also want to replace your fuel filters.
If it is gas, drop the tank and get it flushed and coated. Many radiator shops will do this for you.

[crasster]

I'd inspect before I replaced, but to each their own. May be a perfectly fine tank. If the tank doesn't have rust and if it were me I'd just siphon the gas, add fresh gas, marvel mystery oil in the gas, and a bit of marvel mystery oil to the oil. May be worth adding a drip of oil down each spark plug hole (when the engine starts it WILL smoke), but this is to lubricate the cylinder a bit.

[J-Rooster]

I had my tank removed by a Winnebago Dealership several years ago. The Dealership removed the fuel tank bands, used a transmission jack to lower the tank then siphoned out the fuel to inspect the tank.