[BikingTim]

Does anyone here know the answers to these 2 questions:
1)  What is immediately upstream and downstream of the oil cooler?
2)  Is the banjo fitting for the oil cooler at the entrance or exit of the cooler?

A banjo fitting seems restrictive for fluid flow that is meant to cool an IC engine.
Why would an engineer specify such a fitting?

BikingTim

[The Old Coot]

It all depends on the design. I've seen Banjo fitting that could flow more than the hose feeding them. It depends on how many ports are drilled the cavity size and other factors. Add to that the fluid has to have time to transfer heat to the radiator where it can be transferred to the air, flow it too fast and very little cooling will take place. I had a Buell and Eric had a nice air/oil cooling set up but the cooler itself look way to small BUT it was matched to the flow and did the job just right. Remember the oil needs to be at operating temperature NOT ice cold.

As to the upstream/downstream no real idea. Likely it's fed from the filter and to the head/mains, but not sure on the setup RE had.

[wildbill]

check out part 3 of my 650 test coming up shortly and I will video the oil cooler and you can decide for yourself

[BikingTim]

. . . the fluid has to have time to transfer heat to the radiator where it can be transferred to the air,
flow it too fast and very little cooling will take place.

OTOH, stop the flow entirely, and NO heat transfer will take place.  And doubling the flow rate halves
the heat transferred by the radiator per unit flow while letting each unit of flow having only to absorb
half the previous amount of heat.  It's not clear to me that changing the flow rate affects the cooling
efficiency, but it may affect the amount of work the oil pump must use to produce a higher flow rate.
The banjo may, therefore, limit wasted energy by limiting the cooling oil's flow rate.  It may be that
only that Harris Engineering would know the answer to this.

. . . Remember the oil needs to be at operating temperature NOT ice cold.

OTOH, the oil is specified as synthetic 10W50 - free-flowing even at low temps.

BikingTim

[BikingTim]

check out part 3 of my 650 test coming up shortly and I will video the oil cooler and you can decide for yourself

That would be great if you could show which way the oil flows through the cooler,
i.e. to the banjo or from the banjo.

BikingTim

[ace.cafe]

Harris Engineering is a frame shop. They are not involved in engine design.

Banjo fittings have been common in oiling systems for many decades. They work just fine. All Bullets have always had them.

The engine is primarily air cooled. Any cooling done by the oil is secondary.

Regarding the cooler taps, they appear in photos to be on both sides of the oil filter mounting location. While I have not seen the oiling passages diagram, typical practice would be oil pump to oil filter to oil cooler and then to engine. If they use a split pump feed, the cooler could either be in the line to the crank or to the top end. In either case, it should be in line after the filter.

[BikingTim]

Thanks!  It's interesting that the oil cooling provides just secondary engine cooling.
I had noticed that water radiator hoses were much wider in comparison to oil cooler
hoses, and specific heat of oil is about half that of water, and yet oil coolers were
smaller than water coolers - all pointing to oil coolers not doing much under normal
conditions.

Regarding the cooler "taps", one of the YouTube videos about the cost of the first
dealer service of an INT650 showed that one fitting is bolted to the crankcase, and
the other could be seen to be a banjo hanging loose and dripping oil.  My inquiry
here was to see if it might be worthwhile to substitute Aeroquip type fittings with
full diameter 90 deg turns instead of a banjo/bolt fitting with its (3) sharp 90 deg turns
which restrict flow rate.  In the case of my elderly Fiat, the lower resistance of the
clutch slave cylinder actuation could be felt when I substitued Aeroquip fittings for
the OEM banjo/bolt because, unlike brake lines which primarily trasmit pressure,
the clutch line transmits fluid flow - like an oil cooler does.  From what you say,
though, it wouldn't be worthwhile because the increased oil flow wouldn't provide
much additional engine cooling.

BikingTim

[wildbill]

couple of photos in my review section but will video it for you later

[ace.cafe]

After seeing the photo in Wildbill's review, I would speculate that the banjo under the oil filter is the feed to the cooler, and the other hose is the return.

I see no reason to not change it to AN type fittings and braided hose from Aeroquip or Earl's Supply, or something like that, if you want to. It would look great.

[BikingTim]

[ . . . ]I would speculate that the banjo under the oil filter is the feed to the cooler, and the other hose is the return.

I see no reason to not change it to AN type fittings and braided hose from Aeroquip or Earl's Supply, [ . . . ]

The Neo Earl's Supply is only 7 miles away, so I'd have the hose(s) made up there and then have the nipple's
base threads machined from a larger diameter nipple to match what I expect are millimeter threads on the crankcase.
Gotta see and feel one of these bikes in the flesh, though.  There aren't too many around, yet.

BikingTim

[Dr Mayhem]

Does anyone here know the answers to these 2 questions:
1)  What is immediately upstream and downstream of the oil cooler?
2)  Is the banjo fitting for the oil cooler at the entrance or exit of the cooler?

A banjo fitting seems restrictive for fluid flow that is meant to cool an IC engine.
Why would an engineer specify such a fitting?

BikingTim

I would categorize the oiling system as high pressure, high velocity.

Oil leaves the pump and enters the cooler. it's a 72 psi system so the cooler sees 72 psi. It needs to be restricted (designed)
to be in the cooler the optimal amount of time.

Leaves the cooler and enters the filter. Leaves the filter into the main oil galley. All the feed passages terminate in jets (restrictions) to maintain high pressure.

I'll bet that even at high altitude, with temps above 110 degrees Fahrenheit, traveling at 85mph up a long mountain grade you'll see pressure no lower than 65 psi