# Now steel gas tanks! Why? Why? Why?



## JLawrence08648 (Jan 15, 2017)

I love plastic gas tanks. I thought it was a wonderful invention when they started to become popular in the early 80s. You can drain the fuel without rusting as you would with a metal tank. Metal tanks you have to keep fuel in them year round unless you spray the inside with an oil even then there could be a chance of the moisture in the air rusting the tank.

My first commercial three walk behind mowers, 32" Bobcat, 48" Bobcat, 61" Bunton, all had metal gas tanks, plus my Giant-Vac leaf blower, all bought 1979-1981 and my mid 70s Gravely, all had steel tanks and all rusted.

Now I'm sold on plastic. They don't chip, don't rust, and are easier to screw on the gas cap than metal.

Now I am shocked that the Chinese engines that are not only on snowblowers but also on leaf blowers, power washers, other, have steel gas tanks. Why? We have regressed. Next, these tanks are of such shapes they can't be replaced with a rectangular tank. And they have no shut off valves, and no accessibility to install one!

If you have a steel tank, should we seal it with Jeremy or similar?


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## e.fisher26 (Nov 6, 2016)

Probably because Honda uses metal and Chinese Mtrs use same design


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## sscotsman (Dec 8, 2010)

I have always wondered about this steel vs. plastic gas tank question..
Because there are a ton of 1960's and 70's snowblowers out there still using their original metal tanks, and it seems there has never been a problem..(or at least, seldom a problem)

I've been using my 1971 Ariens for almost 10 years, I never have the tank 100% full..and I have never had any rust..its also gone almost 50 years with that original tank.

I can see where plastic tanks might be better, because they dont rust ever.
but it also seems that rusting isnt a major issue with metal tanks either..

maybe for a small percentage, I do believe there is some actual tank rusting going out out there, but overall there doesnt seem to be a huge rust problem out there.
and many tanks are still being made new, of metal..

So..why do most metal tanks never rust then?
Im actually asking!  not being sarcastic..I dont know the answer.

Scot


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## ELaw (Feb 4, 2015)

I've wondered the same thing!

When I was young, I had a 6HP Tecumseh that lived on the snowblower in the winter, and various minibikes and go-karts in the summer.

That engine had a metal tank, and even though at one point I dented the top of it with a hammer to clear the frame rails on a minibike, it never showed a hint of rust.

I didn't think about it much at the time but I wonder if it was aluminum? If it was steel, maybe it was galvanized?

I've owned motorcycles before with non-galvanized steel gas tanks and rust definitely *is* a problem with those.


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## e.fisher26 (Nov 6, 2016)

Would keeping the tank empty promote more rust? Or keeping water treated gas in the tank be better?


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## cpchriste (Jan 19, 2014)

I, for one, have seen plenty of rust in steel tanks. With ethanol/water separation, the rust issue will only get worse. 

Plastic tanks only, please. Now could we also please get rid of the seams in plastic tanks?


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## snowflitesly (May 5, 2016)

metal tank punched and pressed are cheaper to build than pastic tank molding procedure. U get more metal tanks done in the same time frame as one single polymer molded tank (i'm aware that multiple molding is done, just pointing out it takes longer). Then the molded tank need to cool before going down the fabrication chain. The metal tank once its pressed into shape, your done, glue and cramp the top to the bottom and voila. 

Metal tanks have been around for ages during this internal combustion engine era, why they rust may be part of negligence of the owners. The only ones i saw rusted was from machines that were left to rot in fields, barns or scrap yards. The ones that are used regularly or properly stored don't seem to rust. I don't see a problem here.


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## Spectrum (Jan 6, 2013)

I too have had good luck with vintage steel gasoline tanks and since going to dry storage I haven't seen an issue crop up. So, in that respect I see plastic fuel tanks as solutions in search of a problem. I can't dispute that plastic won't corrode.

Plastic is a great solution when an organic shape is needed such as in a chainsaw or similar piece of compact OPE.

I have seen plastic gas tanks with cap threads that lacked the integrity to secure the cap. I have also seen plastic tanks with molded outlet barbs that could be broken or stressed with a careless move. 

A steel tank isn't just stamped out. Multiple parts are involved and some combination of crimping, welding and maybe soldering. That's multiple forming and assembly operations. Coming from offshore most likely done at manual or semi-automated stations. The plastic tank is probably rotationally molded, perhaps blow molded but the labor content is low, most of the capital lasts along time and apart from the dedicated molds can be used for many products in its lifetime. Plastic is bound to be cheaper.

The biggest challenge for both materials is mounting when you consider vibration. Bands or clamps that can engage molded features seem to have that under control. 

I think either can be a fine solution but if an organic shape is not needed my heart is with steel.

Pete


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## 524SWE (Jan 20, 2017)

Always wondered the same thing, maybe it is the ethanol in our gas and either not being able to fill them up completely or empty them completely. Also since gas tanks on carb equipped, gravity feed fuel tanks need to be vented moisture laden air is going to get in eventually and help start the oxidation process. Once I've encountered a rusty gas tank no matter how clean I've managed to get it I always find a way to install a fuel filter to prevent any left over rust from getting to the carb.


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## UNDERTAKER (Dec 30, 2013)

*The new metal tanks are a new breed of alloy. that is imperverious to rust and oxidation. where as the old school tanks were made mostly out of sheet metal.*


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## drmerdp (Feb 9, 2014)

I have many machines with metal gas tanks, some quite old, some new.. Some that are always stored full with stabilized fuel and some that are stored empty. 

The old machines are tarnished inside but not rusty, and the new are well, still new. 

I'm impartial to fuel tank construction. Though metal tanks are more visually appealing. Dare I say snazzy?


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