Long time coming

I have waited a long time for some parts. I've sweated and strained the grey mush in my skull to come up with a coolant layout that would work for my Bus and importantly, work for others as well. 

While scratching my own itch, I've been down two failed paths. The first (VolksarU-0.1) was placing scirocco style radiators in-bay only to discover that 'prior-art' examples were more the product of P.T. Barnum than Earnest the Engineer. The second failed path (-0.2) was a feasibility study on emulating the Fellows Speed Shop design, only to discover that FSS hang their coolant tubing even lower than their radiator! That one was abandoned without spending anything more than my time. (Which without money is all I have had much of this winter.) So much for the dead ends that VolksarU ran down so you don't have to.

The third shot (VolksarU-0.3) looks the most promising, and like most good work, it comes from a mashup of the best works of others, and lessons learned from all of those dead ends.

• The engine compartment coolant piping from the engine outlet / inlet to the heater wye hole in the rear transverse frame member is designed and fabricated by Rocky Mountain Westy.
• The low profile scoop and underbelly radiator concept from Fellows Speed Shop, redesigned with my own break-away scoop and the Champion Cooling EC281 radiator standing in for their custom radiator (at 1/8 the cost and made of the same materials.)
• My coolant piping design to bridge the gap between the connection to the engine bay via the heater wye hole to the radiator itself. The design's chief features are:


• Durable: Built from 304 Stainless Steel, the same material used in the replacement coolant tubing provided by companies like GoWesty, and Rocky Mountain Westy as replacement coolant tubing for the plastic factory tubing in the Vanagon. The Bus may rust down to a pile of brown goo, but this coolant tubing will still be there.
• Compact: Mashing Gates Greenstripe flex hose in the confines of the central box space of the frame is simply a no-go: They're not rigid enough, and they're so fat they won't fit down that narrow space between the radiator and the inside of the frame rail. You can't run them outside the frame rail without putting them at risk of road debris, and looking like an extra from Mad Max. Hose will want to follow its own internal desire to turn itself back into a straight line and puts stress on its end couplers because of it. In short, a hose with an ID of 1-1/2" (the size of the output and input of the EJ22 engine) will have an OD of about 2". Which is too pudgy to fit down that narrow corridor inside the frame rail. So you've got to go thin and rigid, both to fit in the space and to retain unlikely shapes without stressing the couplers, which can cause leaks.Ergo, tubing. Not hose.
• Thermally Conductive: As mentioned in a previous post, hose is an insulator. (It may not seem like it if you've ever grabbed a hot coolant hose, but compared to touching a metal radiator tank at running temperature...hose is an insulator.) Since our cooling ability is already compromised by the orientation of the radiator, best to be throwing off as much heat as possible as fast as possible before, during and after your coolant passes through the radiator. Also, any portion of coolant tubing in the engine compartment is also being cooled by the air scooped into the engine compartment from intakes at the rear corners of the Bus.
• Protected: All of the coolant tubing and radiator is above the frame of the vehicle. You would have to tear the scoop off and run aground first and the chances for your radiator and coolant tubing's survival are better than 50/50, even if you lost the scoop. Keeping all of the coolant tubing above the level of the frame leaves them especially well protected. Short of an in-bay solution, this combination should produce the best of all worlds without bankruptcy as a side-effect of success.

With my six pieces of mandrel bent SS from Columbia River Mandrel Bends in Saint Helens, Oregon, I'm ready to have the radiator modified to move the inlet / outlet, then have the tubing TIG stitched into three assemblies. 

Assembly #1 allows it to jog from the original heater wye hole into the left hand frame rail and forward to the front (previously top) of the radiator where a hose coupler attaches it to a U-bend (Assembly #2) and into the radiator via a hose coupler at the front left.

On the output side of the radiator, we exit at the right rear through a hose coupler and into Assembly #3 which is two 90° elbows cut and stitched into a jog that takes us back to the heater wye hole. 

That's the circuit for the most vulnerable part of the cooling system.

The final piece of fab is the scoop which will be fabricated of steel panels, two angle brackets and a reinforcing strap, any shop should be able to knock this out in under an hour. Between the TIG work for the tubing assemblies and the MIG work for the scoop the price should stay reasonable.

Remember the VolksarU policy on bespoke fabricated parts: Avoid when possible, but if necessary, work from plans. I'm hoping to lure someone with a CNC mandrel bender into fabricating all of the tubing assemblies from single lengths of tubing instead of doing TIG work to put them together.