Oil cooler thermostat (bedtime reading)...

Status
Not open for further replies.
Jim did test the ‘more oil to the head’ theory and it came up negative. De bunking my theory!

Eddie, please post a link to that test finding. From the thread "Increasing oil flow to the head", Jim's statement isn't backed by an experiment. His statement "without doing any meaningful cooling to the head" sounds rather vague to me. How much is "meaningful"? Maybe Jim relates to what the std. oil pump may deliver. Of course the oil gets hotter, that's the whole point of wanting a heat transfer! And it makes fitting an oil cooler meaningful or even necessary.

-Knut
 
What about specific hot spots, will these spots be able to lose heat faster better if the general temps of the head a lowered?
How much of a drop probably matters too.
Perhaps Jim will speak to this.
 
Aluminum is a very good head conductor and I don't expect to see sharp thermal gradients. There is no "general temperature" of an air-cooled head. In the case of steady-state heat generation, temperatures will decrease steadily towards the outer end of fins. Even for an encapsulated head, the front part would be hotter than the rear part due to cooling of the intake charge.

-Knut
 
Norton oil delivery seems to me to be adequate in every aspect with my concerns being focused mainly on the climate in my region. High summer in this area typically runs upper 90's-lower 100's with very high humidity, so dissipating the heat to preserve the old motor is #1 on my list....Oil is relatively inexpensive compared to a Commando motor in my view & Castrol gets nasty looking quickly in summer heat. Downright distasteful.
 
I used to think that modern oil could handle anything a Norton couldmthrow at it, and th email benefits of a cooler were to cool the oil in order to cool the engine.

Jim’s oil testing showed that actually, our old engines generate heat and conditions inside that quite quickly degrade the oil.

The engine itself seems happy coping with the heat produced.

So a cooler is actually more beneficial to the oil. Basically the opposite of what I thought!
 
So oil cooler potentially = slightly extended serviceable oil life. I'll buy that for a dollar because it does make sense. If heat is causing damage to the oil it in turn is not fully accomplishing the task of lubing, cooling, & slowing wear is how I'm reading this. Please correct my mental picture if it is flawed.
 
So oil cooler potentially = slightly extended serviceable oil life. I'll buy that for a dollar because it does make sense. If heat is causing damage to the oil it in turn is not fully accomplishing the task of lubing, cooling, & slowing wear is how I'm reading this. Please correct my mental picture if it is flawed.

That’s more or less how I see it.

Different oils perform massively differently. Some degrade quickly, other not so. Fortunately this has been looked at in detail already.

If you haven’t already, you should digest this:
https://www.accessnorton.com/Oil-Tests/NortonOil.php

And the thread from whence it came, but you need to read all 50 pages, to get a star:
https://www.accessnorton.com/NortonCommando/follower-scar-oil-tests.25898/

Be warned that after reading this you’ll likely change your oil of choice...
 
Read it, but old habits die hard. I just have it imprinted from it being in the old manual and have always stuck with it, but have been eyeballing one of the others particularly hard. Perhaps I'll make the change after a couple of hundred miles because I've only about a C on this tank... Patience for this is still the first tank of unlead ever to burn through her, and from what I'm seeing she rather likes the stuff & wants more.
Off topic: I did a read on cleaning rust from gas tanks. Battery charger, steel rod, washing soda, & water. Worth a google. Best cure I've seen. Results look like new.....New to me anyway.Just sharing. Don't recall where I saw it mentioned to give credit.
 
... and / or increase your change schedule...


That really does nothing for thermal breakdown of the oil. Once the oil is cooked, it’s smacked, regardless how fresh it is. Unless it is changed immediately after it’s been cooked, you are running on a degraded lubricant. Thermal breakdown is not accumulative.
 
That really does nothing for thermal breakdown of the oil. Once the oil is cooked, it’s smacked, regardless how fresh it is. Unless it is changed immediately after it’s been cooked, you are running on a degraded lubricant. Thermal breakdown is not accumulative.
Exactly .Little point in cooling cooked oil .
Putting burned toast in the freezer isn't going to make it edible .
My advise : don't read it ! It will only disturb your peace of mind .
Wonder how I ever clocked over 450 000 km on Nortons without knowing anything about oils ..:)
 
“My advise : don't read it ! It will only disturb your peace of mind .
Wonder how I ever clocked over 450 000 km on Nortons without knowing anything about oils.”

Begs the question: how many Nortons and how many rebuilds?

I can’t say about the present, but back in the day when we thought oils were just oils, Brit motorcycle rebuilds, especially top end, were quite common with less than 20,000 miles.

I’d venture to say if one were to study the results of Jim Comstock’s extensive oil testing and chose oil accordingly and you used a thermostatically controlled oil cooler you would get many more miles before you had to open ‘er up.
 
Last edited:
Exactly .Little point in cooling cooked oil .
Putting burned toast in the freezer isn't going to make it edible .
My advise : don't read it ! It will only disturb your peace of mind .
Wonder how I ever clocked over 450 000 km on Nortons without knowing anything about oils ..:)


The purpose of an oil cooler is to keep oil from being cooked, not cooling cooked oil.
 
By definition, IF you can supply enough volume of cooling oil flow, then, ipso facto, it will not over heat AND it will improve cooling of head.

The obstacle is inadequate drainage which prevents sufficient cooling oil volume. What I am saying here does NOT argue with Mr C.

Edit - the second obstacle, as Mr. C notes, is scavenging. Even if you did find more volume AND more drainage, then the stock internal pump couldn't keep up and excess oil in the crankcase would be whipped into high temps.
 
Last edited:
I think Jim feels it is not possible or perhaps not practical to try to cool the head with oil flow or even oil flooding.
So at this point Ive taken it off the option list. I would go to a cooler with thermostat if I rode in a hot climate and
or long distances. My worry probably is lack of hot enough oil to evaporate water and any petrol thinning.
 
The oil still gets hot even running a cooler, in over 40 years of running a oil cooler without a themo I have never encountered water in my oil from the oil not getting hot enough even riding in winter, but then I don't live in a cold climate.

Ashley
 
ashman
just taken my non oil cooled 850 off the road to replace rear chain and sprockets,sprag clutch and new Duplex primary setup and can say you would definitely get emulsified oil on short runs in the (relatively mild) southern England winter temps we have at the moment with the lowest start temp so far being minus 2°C or 28.4°F.
My work ride direct is only 5 miles but I go the long way round for 11 miles and this is barely enough to eliminate emulsification in the oil tank or cylinder head, especially on the intake side where it can be seen if the rocker cover is removed.
New route is around 15 miles with a couple of fast stretches and this only just does the trick, 25 miles would be ideal but it goes to show that in colder climates, an oil cooler with thermostat is a positive move.
My FJ1200 being used now has a stat and it,s barely open on the same route, the oil cooler only hand warm, and this on a big wet sump engine which pops the stat in 10 miles during the summer.
 
Last edited by a moderator:
ashman
j you would definitely get emulsified oil on short runs in the (relatively mild) southern England winter temps we have at the moment with the lowest start temp so far being minus 2°C or 28.4°F.
My work ride direct is only 5 miles but I go the long way round for 11 miles and this is barely enough to eliminate emulsification in the oil tank or cylinder head, especially on the intake side where it can be seen if the rocker cover is removed.
New route is around 15 miles with a couple of fast stretches and this only just does the trick, 25 miles would be ideal
 
Status
Not open for further replies.
Back
Top