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Using oil cooler for water?
cloudy - 20/5/08 at 10:18 PM

How stupid an idea is using an oil rad like:

http://www.rallydesign.co.uk/product_info.php?cPath=340_367&products_id=2260

for water cooling? It's available with 20mm inlets

I'd like indentical rads both sides on my middy so would be handy to use the same model twice.

James

[Edited on 20/5/08 by cloudy]


blakep82 - 20/5/08 at 10:22 PM

i guess it would work, but aren't they a lot smaller than a normal water radiator, like you might end up needing 4 of them... what about motorbike water radiators?


cloudy - 20/5/08 at 10:26 PM

With two of those I have a similar total area than the water+oil cooler on the original bike...


mookaloid - 20/5/08 at 10:38 PM

What are they made from?


907 - 20/5/08 at 10:57 PM

I beleive a VFR has twin rads.

Paul G


nitram38 - 21/5/08 at 07:31 AM

Cloudy, I know it wouldn't be cheap, but why not get proalloy to make you two rads?
Each could have different cores and pipes fittings but at least they would be the same size.
If you do have an oil rad the same size as the water, make sure that you fit an oil thermostat.
They charges me £240 for a front rad for the motaliera (R1) which has a split header at the bottom:
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Description
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[Edited on 21/5/2008 by nitram38]


02GF74 - 21/5/08 at 07:50 AM

something to think about, and I'm not sure it matters is that pressure in car radiator is limited by cap to about 19 psi - pressure of oil system is at least that and can go up to 90 psi; so that may imply you need a bigger pressure to force fluid through the oil cooler - I am pretty sure I have blown through an oil cooler - as you do - and don't think they are restrictive.

a locost way is to find short (heightwise) car radiator and cut it down widthwise - should be easy to do with brass header tank as you can solder them.

incidentally nitram - the matrix in your custom water radiator - is that an oil cooler type matrix or water radiator matrix?

something else to be aware of - car water radiators have much larger inlet/outlet - typically 32 mm; oil cooler limit to about 3/4 inch BSP fitting and I think the internal hole is smaller than that, not sure. I guess this is matched to the flow of the two fluids, water being pumped at a much higher rate. (rough calc shows you need three 3/4 bsp coolers in parallel to get same pipe area - note that parallel is never ideal as you cannot guarantee equal flow in each component).

Thinkauto make the mocal oil coolers so buy from there - cheapest too. They can make specials.

[Edited to remove spelink eroers by 02GF74]

[Edited on 21/5/08 by 02GF74]


indykid - 21/5/08 at 07:52 AM

from my experience of handling them, they're made of much heavier gauge material to deal with oil pressure and with much less efficient fin design.

the thicker the wall, the less efficient the heat transfer is, so chances are, the efficiency is sufficient for oil, but not water so you'd need an even larger area then your standard rad.

it's a nice idea in concept but flawed i think.
tom


MikeRJ - 21/5/08 at 09:02 AM

quote:
Originally posted by cloudy
With two of those I have a similar total area than the water+oil cooler on the original bike...


In terms of the overall dimensions yes, but the tubes within oil coolers are quite a bit larger than they are in a coolant radiator, so your actual radiating area will be down.


nitram38 - 21/5/08 at 02:50 PM

02GF74, my rad has a water core.............
The inlet/outlets are 25mm dia, same as the R1 water system.
The top small pipe (6mm) is for an air bleed back to the expansion tank.

If you do go the cut down rad route, make sure that you submerge the core in water while you re-solder the header tank, otherwise you could find yourself picking up a pile of nice shiny bits!

[Edited on 21/5/2008 by nitram38]