Aluminum AN fittings?

off_road2

off_road2

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Location
Hickory
I can't seem to find any information about this anywhere on the internet so maybe yall can help...I'm wanting to run 3/8" steel tubing for my fuel lines and remote trans cooler lines. Prefer steel for greater strength and safety. I want to use -AN fittings (nut, sleeve, barb) for the transitions between hard line and flex.

The question is can I use the much more easily found aluminum -AN fittings (instead of steel fittings) with a flared steel tubing? I would never ask this for brake line applications but for this 100 PSI and less stuff will the aluminum -AN seat and seal in a steel flare?

I understand the mixing of dis-similar metals is not preferred for corrosion, but the trans and fuel don't contain water so the corrosion betweent he two will be minimal.

Thanks for the help.
 
Don't mix them. I have seen several crack and was told it was because the steel "eats" out the alum. because its that much softer....
PM me and I can get you in touch with Bill from Alliance. He is the man.
 
I've done exactly what you stated, 3/8" fuel hard line, with a nut and backer on, then single flared. Coupled to standard AN stuff. I try to use alum or steel where I feel its a good fit. On fuel I use alum. As I find the steel corrodes and looks shitty in 6 months. (Even plated start looking like ass ) Alum works fine etc.. On steering nothing but steel fittings so I can ensure things get tights and I don't wory about rounding off a fitting..


That said... I'm looking to run OEM style thermal plastic lines on my current project.. :D
 
I work with alot of aluminum stainless and steel. I have seen all three mated (mounted) next to each other with all types of lubricants, barriers, paint coatings excetera on the surfaces.

Any disimilar metals joined in a confined area with or without moisture present will cause a type of corrosion. Aluminum directly to steel or stainless is the worst combination.

Each metal in affect has its own electrical characteristics in a static neutral state. These varying static charges and densities of material cause electrolisis (sp). Its the natural act of the two materials trying to equal each other and become neutral. Its basicly an aggressive Ion exchange.

Older large aluminum tanks used to contain bars inside them to take the (charge) so to speak and become sacrificial members within the internal structure. Electronic devices have also been constructed with the same intent, along with suposed prevention of the natural rusting of Iron by controlling the electric discharge of ions.
 
Oh and before anybody says well what about trans housing and aluminum diffs excetera. Cast aluminum is like cast steel it has many varying compositions that have alloying elements to serve various uses. One being the ability to fight off this electrolisis. Plain sheet stock flat bars and AN fitting don't contain these elements because they make forming and machining more exspensive. One of these elements is maganese in trace amount, which adds to its hardness. Casting allows manufactures to taylor metal properties for enhanced characteristics.

However you ever notice how an early Ford intake gets real chalky with age and flakey around bolt holes? Or the old trans layed out back for ages getting all pitted and brittle?
 
I don't travel enough to stay at those, but I like the ones that have the waffle makers for breakfast.

Seriously though, Metalurgy and the physics behind metals sort of trips my trigger.
 
I'd be interested to hear what you find too as I've got a lot of brake and fuel hardline going in soon and already bought al fittings. I'm not really worried about the dissimilar metals aspect of it because I don't expect any of it will last 20 years anyway, but I wouldn't want it cracking or anything. That being said, as long as you don't gorilla-tight the fittings, I can't really see problems with cracking either? Anyone have first hand experience of aluminum AN fittings failing in a short amount of time?
 
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