tr5 Stainless petrol tanks

[harrytr5]

Does anyone know who can make s/s petrol tanks for TR5/6 injection models.I have a price for around £600

for a one off.If they are manufactured already where can I buy one from. Alloy ones I have used in the past

and do not want to go that way again.The last one I got from CTM around ten years ago and he is not making

s/s currently which is a shame with all this ethernol stuff in our petrol.I was ahead of the game by default

ten years ago with all rubber hoses changed to teflon lines s/s outers.

So does anyone manufacture S/S tanks at a good price or is £600 a good price anyway.

Regards Harry.

[AlanT]

You will need to be very careful wit the type of stainless you use.

Don't assume that stainless steel does not corrode at all.

 

We ran a machine for flow-soldering circuit-boards. These received a flux coating on their journey.

One Monday morning we came in the find the floor flooded with liquid flux.

 

But we could not find the leak. Eventually I found that the tank had become porous, being riddled with tiny holes. A bit like woodworm in stainless steel. The flux was a non-acidic organic resin.

 

You get a similar problem in dairy machinery I believe.

 

Anoher problem is that the elements used to alloy the steel and make it stainless will tend to get driven out by the welding process.

So the welds won't be as stainless as the rest.

 

This is not as simple as getting some stainless sheet and TIG welding it up.

Well you will make a tank of course. And it will hold for a while. But it might not be much better than just using mild-steel.

[Rodbr]

Harry,

I would highly recommend Andy Wiltshires work. Not the usual spit thin ****.

Lots of possible options and a very good reputation. No connection just a happy customer.

 

 

http://andywiltshire.com/Triumph%20TR%20Tanks.htm

[RogerH]

Hi Harry,

be careful what you select.

The original steel tank also stiffened the bodywork up. The steel tank was ductile enough to gently give a little without breaking.

Ali and Stainless have different propertise that may not be as good as you want.

 

Roger

[TorontoTim]

Hi Harry,

be careful what you select.

The original steel tank also stiffened the bodywork up. The steel tank was ductile enough to gently give a little without breaking.

Ali and Stainless have different propertise that may not be as good as you want.

 

Roger

As mentioned on the Forum fairly frequently, a firewall between tank and passenger compartment is a good idea. If you added one in steel, I'm thinking that might substitute for the body-stiffening effect of the steel tank...?

 

FWIW, I also recommend Andy Wiltshire - top quality work.

[Alec Pringle]

Hi Harry,

 

as Tim suggests, a firewall is a damn good idea. Properly installed, it will more than compensate for the petrol tank in terms of stiffening the rear bodywork, which can only be a good thing.

 

Stainless steel tanks are heavy, and don't take well to the stresses that a relatively flexible separate chassis construction tends to impose on them, you'd need to consider the mounting arrangements carefully. As for what biofuel might do in due course, that's another subject that might bear further investigation ?

 

Andy Wiltshire's aluminium alloy tanks are excellent - I've inspected several, they are professional motorsport calibre, and as good as any I've ever seen.

 

I've also had a lengthy discussion with him about construction techniques, and the appropriateness (or otherwise!) of various material specifications employed in tank manufacture. He spent an evening here measuring up a TR7 with its tank removed a few years back, an educational experience for me.

 

There aren't many specialists I'd recommend unreservedly, but he's one of them.

 

Need I add, the waiting list for a tank is several months, not weeks, but he does seem to stick to his delivery dates. There is one major problem, as Matt found with his TR6 last year, and this year Julian with his TR3A - the almost irresistible impulse to mount the tanks as a wall display, it's a work of the fabricator's art and it seems a crying shame to bury it in the back of a car.

 

Usual disclaimers . . . . .

 

Cheers

 

Alec

[harrytr5]

My Stainless tank has been in my Jasmine TR5 for ten years with no problems at all.My mates and I are after more as ethernol does not attack it like steel.Did not know about that Alan ,but thanks for the heads up.

Regards Harry

[harrytr5]

Thanks Alec,

Will look into this as well.Fire wall looks so appealing that I will look at that as well.

Regards Harry

[Guest ntc]

Funny that ? as all the tankers up our way are stainless both for milk and crude oil and have been for years.

[AlanT]

I didnt say you couldn't do it. Just that you need to select the right grade of material.

I'd guess if you are making tankers you have worked this out by now.

 

Sounded to me as if Harry was intending to just get someone to make one up at £600.

Not all fabricators are totally clued up about material selection. Thats why our flux-tank failed.

 

Whatever you do this will have a service life.

[Peter Cobbold]

Ethanol in really aggressive conditions is OK in either 304 or 316 - so petrol at 5 or 10% certainly safe.

http://ethanolproducer.com/articles/8853/stainless-steels-cost-effective-materials

Dont know about welding tanks in ss but these guys seem to:

http://shop4tanks.co.uk/special-order-tanks.html/

Shall be going that route with my 100% ethanol tank.

Peter

[Ragtag]

Harry,

 

Colin at CTM does stainless tanks in either standard or larger capacity. If memory serves, a couple of years ago they were in the region of £300.

[harrytr5]

Thanks Ragtag,

Colin is not making anymore which is why the appeal for someone who is.

John Sykes (TR Bitz) is looking into it and hopefully coming up with a positive answer this coming week.

The more he is aware of what we need, it might just get done.TR Bitz tel no 01925 756000.

Regards Harry

[harrytr5]

Thanks Peter.

That article makes for very interesting reading and vindicates why I went down that route ten years ago.I want to update my project TR5

in that department hence the appeal.

Regards Harry

[AlanT]

Whats the problem with alloy tanks?

[Peter Cobbold]

Whats the problem with alloy tanks?

Its not simple.

Neat ethanol - the stuff I have to handle - and particulalry methanol dissolve the protective oxide layer off aluminium. So corrosion can be rapid. As fast as the protective oxide film forms it is dissolved by methanol! Racers using methanol fuel have to wash ali tanks and carbs free from alcohol after a day's running.

 

Road petrol E5 and maybe E10 might at first sight seem to be OK as water in the fuel promotes the oxide film formation:

http://www.sciencedirect.com/science/article/pii/S001623611000520X

"This study examined the effects of dissolved oxygen on the corrosion properties of aluminum cast alloy, A384, in bio-ethanol blended gasoline fuel at 100 °C. Oxygen enhanced the corrosion resistance of the alloy by forming a protective hydrous oxide film. The acetic acid and water produced by ethanol oxidation in the fuel had a corrosive and protective effect, respectively. However, the protective hydrous oxide film enhanced by the water suppressed the corrosiveness of the acetic acid in the fuel when the two by-products coexisted. Therefore, the water formed by dissolved oxygen in the bio-ethanol blended gasoline fuel enhanced the corrosion resistance of the aluminum alloy by promoting the formation of a protective surface film."

 

BUT if the fuel is dry enough to meet EU specs, "dry corrosion" might become a problem:

http://link.springer.com/article/10.1007%2Fs10853-011-6108-1

 

On the other hand, dry corrosion is not seen at low ethanol percentages and room temperature:

"Behavior of dry corrosion which is electrochemical reaction between Al-Mg-Si alloy 6063 and ethanol in gasoline has been investigated. Dry corrosion has not been observed in E3 (3% ethanol) and E10 (10% ethanol) at room temperature, but observed in E3 and E10 when a small amount of aluminum chloride had been added to them at room temperature. The higher solution temperature is, the more often the dry corrosion occurs. Dry corrosion has also been observed in the above solution environments in which 0.1% and 1% water contained. Occurrence of dry corrosion was detected by the area polarization method, which revealed that initiation and propagation of the dry corrosion corresponds to the decrease of anodic polarized resistance of 6063."

http://astp.jst.go.jp/modules/search/index.php?page=DocumentDetail&journalId=0021-4876_73_11_Corrosion+Behavior+of+Aluminum+Alloy+6063+in+Gasoline+with+Ethanol_N%2FA

 

There is also the composition of the alloy to contend with: do susceptibilities differ?

 

However these experiments used raised temperatures and did not use any of the corrosion inhibitors present in petrols. IF these inhibitors are designd to reduce ali corrosion then it should be OK. FBHVC were once planning to assess corrosion inhibitor additives for E5 and 10 petrols. The protocol and other details of this study have not to my knowledge been published - I cant find it on the FBHVC website. Which is perhaps a reflection of the complexity they uncovered.

 

So no clear answer.

 

Peter

Edited April 20, 2014 by Peter Cobbold

[Alec Pringle]

Alloy steel or alloy aluminium alike need to be the right material for the job, there are dozens of alloys available in sheet form but they many will not suffice for fuel tanks, and equally important the welding technique and the tank mounting have to be appropriate.

 

The ethanol biofuel content adds another dimension in comparison with previous road fuel formulations, drastically reducing the potential material options.

 

As Neil points out, the roads are full of stainless steel commercial tankers - and I'd guess these are constructed to strict specifications by established companies who understand exactly what they are about . . . .

 

In contrast, I've seen many fuel tanks in the past constructed by well meaning folks who might well have been adequate fabricators in a general sense, but who knew notalot about the priorities of tanks for motor vehicles, road or race. Some of those inadequate offerings, I might add, made for TRs.

 

As a personal view, I'd prefer to think that ten or twelve gallons of highly inflammable fuel sitting a yard from my backside is contained in a tank which I can rely on - in normal use, and in an accident situation.

 

Which is why, having some past knowledge of fuel tank specification, I recommended Andy Wiltshire.

 

Cheers

 

Alec

[AlanT]

I wouldn't be surprised to find the tankers have an internal polymer coating.

Also maybe annual inspection.

And get possibly get scrapped every 5 years.

 

The tankers are also carrying liquid of known quality, ie fresh stuff.

 

Our flux tank was full of well used flux that had been cooked up by frequent use. This probably turned it acidic.

 

I'd prefer aluminium myself because the welds can be made without degrading the "stainless" aspect.

[Peter Cobbold]

There is a lot of info on modifcations for E85, including suitable aluminium alloys and anodising.

 

eg http://news.motorsport.org.nz/e85-and-fuel-cell-compatibility/

"5005, 5052, 5083, 5086, 6061 & 6063 type aluminum alloys are naturally better at resisting corrosion. If you are having a new tank fabricated, you should insist it be made from one of these alloys using 5356 welding. This will ensure best protection and a long service life."

 

Somehwere I recall that an anodised surface can be given more resistance to ethanol by a simple solution coating with nickel.

Edited April 20, 2014 by Peter Cobbold

[AlanT]

Ah some useful material data is appearing. Thanks Peter.

 

The problem maybe getting the right material, in a small quantity, in the UK.

[Peter Cobbold]

Ah some useful material data is appearing. Thanks Peter.

 

The problem maybe getting the right material, in a small quantity, in the UK.

I wasn't aware of the ss weld corrosion issue. Thank you.

 

As polymer tanks are illegal for road use, so for belt and braces with E100 I shall use the correct ali grade tank and get it hard anodised. Then treated with nickel acetate solution and then hot deionised water. Lots of info on this site, eg:

http://www.pfonline.com/articles/duplex-sealing-with-nickel-acetate-and-di-water

 

Or use electroless nickel on stainless, which should protect the welds:

http://www.poeton.co.uk/electroless-nickel.htm

 

Peter

Edited April 20, 2014 by Peter Cobbold

[AlanT]

To get stainless you need a pretty accurate cocktail of iron, carbon and other fancy metals like chromium.

 

As the weld pool cools, regions in which this mixture is not present get frozen in place.

Not all parts of the mixture have the same freezing point.

 

Afterwards these regions are "dissimilar materials in contact" ie batteries and corrosion sites for electrolytic ction.

 

This is why I think aluminium tanks may offer better corrosion resistance.

[Peter Cobbold]

To get stainless you need a pretty accurate cocktail of iron, carbon and other fancy metals like chromium.

 

As the weld pool cools, regions in which this mixture is not present get frozen in place.

Not all parts of the mixture have the same freezing point.

 

Afterwards these regions are "dissimilar materials in contact" ie batteries and corrosion sites for electrolytic ction.

 

This is why I think aluminium tanks may offer better corrosion resistance.

So nickel would be no use at all - the weld will be corroding internally. Nasty.

Aluminium it is then.

Peter

[Clarkey]

Gents

Just to ad my five peneth

The ethanol/alcoline that is used in E5 /E10 has an anti corrosive inhibiter in it,now this is either from source or its added at the terminal before it is put into Terminal storage tanks. The storage tanks have a butyl liner in them.

[AlanT]

Ah as I expected, fuel tanks lined with polymer.

 

And you add an inhibitor because ...

 

I've recent experience with stainless pipes carrying "stuff" that I can't decribe on here.

Welded joints instead of compression fittings were used. Can't bear to tell you the cost to fix this.