machined aluminum radiator (tranny cooler) fittings

BlackSheep

baaaaaaaaaad to the bone
Supporting Member
Hey,
anyone know a source for machined aluminum tranny cooler fittings? I recently bought a Ron Davis Radiator, and the instructions say I shouldn't use dissimilar metals for the fittings. In order to connect my tranny up, I need to find some aluminum fittings. Anyone know where I can find these things?

Also, my radiator cap is steel, also a dissimilar metal. What about sources for aluminum radiator caps?

If you don't have a source, what is your experience in using steel radiator caps on aluminum radiators?
 

timpanogos

Push to the Peak
Location
Heber
I assume the rubber seal will Eliminate any potential problems with the radiator cap

p.s.

give Novak a call ... I believe they are in Logan, but not sure about that. They make the aluminum rads that Mount Logan uses all the time in their builds.
 
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BlackSheep

baaaaaaaaaad to the bone
Supporting Member
quick update:
I surfed through summit racing last night. Did find some anodized alum fittings, but not the right size for my application. Still looking. I have a little time, so I'm not going to use the brass unless I just can't find the right size in alum.

I'll be using teflon tape on the fittings anyway, so is that enough insulation beetween the two metals?

As for the cap, it wasn't so much the sealing part of the cap I was thinking of, it was more the actual locking part. That is steel that comes in direct contact with the radiator.
 

BlackSheep

baaaaaaaaaad to the bone
Supporting Member
Summit does have aluminum radiator caps for $9.95 for their brand.
some of the other brands are $50:eek:

Thanks! I had forgotten to look for caps on Summit.

{edit}
ok, so I went on there, and found only 3 radiator caps for 18psi. Unfortunately, all of them are steel. I found several 17psi, and a few 19psi.......Obviously, the cap pressure rating is like a fuse amperage, so the lower I go, the better protection I get. However, how low is too low? Will 1psi make a difference? Will I be pulling over all the time to let my rig cool down so it will stop spewing? I'll search around for other suppliers, but this might be a good topic for someone doing future research.
**/edit}

{another edit}
Found this page on novak conversions - guide to cooling
pretty good info, it looks like they are reccomending a pressure of 22-24psi. I did see a number of caps on summit in this range.
**/another edit}
 
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bobdog

4x4 Addict!
Location
Sandy
Thanks! I had forgotten to look for caps on Summit.

{edit}
ok, so I went on there, and found only 3 radiator caps for 18psi. Unfortunately, all of them are steel. I found several 17psi, and a few 19psi.......Obviously, the cap pressure rating is like a fuse amperage, so the lower I go, the better protection I get. However, how low is too low? Will 1psi make a difference? Will I be pulling over all the time to let my rig cool down so it will stop spewing? I'll search around for other suppliers, but this might be a good topic for someone doing future research.
**/edit}

The cap pressure is very important. It is a safety device but more importantly coolant will boil at a much higher temperture as pressure increases. Your cooling system will work better the higher the pressure. 1psi diference should not be a big deal but get the 17 psi one I would be nervous going higher than the radiator is rated for (18 is what the Ron Davis calls for and not what the OEM takes right?)

What size fittings do you need?
 

BlackSheep

baaaaaaaaaad to the bone
Supporting Member
The cap pressure is very important. It is a safety device but more importantly coolant will boil at a much higher temperture as pressure increases. Your cooling system will work better the higher the pressure. 1psi diference should not be a big deal but get the 17 psi one I would be nervous going higher than the radiator is rated for (18 is what the Ron Davis calls for and not what the OEM takes right?)

The OEM cap is 18psi. I went to the Ron Davis website briefly this morning, but didn't find a pressure rating. I'm sure I just didn't look in the right place on the site, I'll have to go back and dig some more. Based on the Novak conversion page, I should go with a higher pressure. Of course, that is why I went searching on the Ron Davis website. Once I finally find a pressure rating from the website, I'll order up a cap of the proper pressure.


What size fittings do you need?

The barbed end is 9.5mm (3/8") and the threaded end is 15.75 (5/8"). Based on my little thread guage, it looks like the thread pitch is 1.5mm, so that would make the threaded end 16x1.5.
 

BlackSheep

baaaaaaaaaad to the bone
Supporting Member
update
I sent an email to the sales guy who I worked with to order the radiator. He states that I can use the brass fittings for the tranny cooler, and the steel radiator cap as long as it is 13-16psi. Pretty surprising since their instructions specifically state not to use dissimilar metals. Since I am in a cash flow shortage right now, I think I will be using the brass tranny cooler fittings.

My cap is rated at 18psi, so I will likely order a new aluminum cap rated at 16psi. After EJS, I'll likely go ahead and order some aluminum tranny cooler fittings.
 
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