RPM oil cooler & riding temperature

[Pat Conlon]

As long as the A/B comparison is done on the same FJ.

Different FJ's with different carb jetting = different oil temperatures.

Cheers Alf

[Alf]

Yes, Pat, you're right. But the accuracy of the gauges and if the operating temps are right with different coolers, I think the test will be informative. The oil must be between 90-115ºC

First impression is that the Randy cooler maintain better and get faster a proper operating temperature. But I have to wait a couple of months if it snows at the mountains (not all winters snow) , because here in the island there is not too much cold along the year

And that my near STD 1TX even with the Randy cooler go hotter than my modified 3CV with the FJowners rad. Still my 1TX is running on STD plugs, and running DPR9 plugs are 5ºC difference... but it is true that few people ride those plugs because in cold climates don't work correctly

I will try to make the report so informative as I can do it

[Alf]

And, first conclusion straight ahead: fit always an oil temperature gauge if you make mods on your bike. It gives you the first sight if the bike run lean, when the temp goes up. It happened to me when I graduated the float bowls at minimun years ago: the bike was much faster, but much more, incredible... and in 40 km uphill on tight roads on sport ride mode, the temp went to the skies like a rocket

[Alf]

Well, I´ve finished the tests in my FJs with different coolers and tuned state, you have the conclusions in my website 

I have had myself a couple of surprises!. Mainly, that my near STD 1TX was faster that my moded 3CV

The tests were made in various days, repeated going from bike to bike and changing the order of the bikes, in different days and with different climates... well, not too much here in Tenerife, but 15ºC is cold for us!. The tests were very exhaustive, including tarmac & tyres temperature, and taking engine temperature with 2 different gauges fitted in each bike and with a heat laser gun at the base of the oil filter. To not to overload the article with too much details, I only uploaded to my website the conclusions

I hope this helps

[Sparky84]

G'day Alf

I haven't started the reading yet but you've fallen into the trap we all do this early in the New Year which is 2018 not 2017 unless I'm mistaken and that's when you started

Looking forward to the test results

Cheers Alan

[Alf]

Hi, Alan

Thank you. Corrected... well, after half and hour looking for it 

And the subtitle and the engine section was in Spanish, haha 

[red]

And the oil light flashes a lot of times with the RPM cooler installed, even althought the level is correct. Must I add more oil because the bigger capacity rad?  Thanks

Alf,

I do not know about "must," but for me at least, I certainly would add some more oil to the crankcase.  Randy may be able to tell you how much extra oil the RPM cooler will take.  That amount probably will not be more than a cup-full, but I would want the engine to have the correct oil level when riding on the road.  Once you add the extra oil (if any is needed), your oil level "sight-glass" in the crankcase may appear to be over-full with the bike completely upright.  Still, you can lean and hold the bike slightly to one side to see the top of the oil in the "sight glass" again.  Once you learn how far to lean the bike for an "oil level check," anybody can assist you by reading the oil level glass for you.

The oil warning light is connected to a level sensor (a float, like a carb float).  Going uphill and/or strong acceleration moves the oil rearward in the crankcase.  The temporary lower oil level at the float location can cause the oil light to come on briefly, but it does not indicate a loss of oil pressure.  If the oil warning light stays illuminated for more than a few seconds, THAT would indicate a real problem, and you must turn off the engine immediately.   There is no oil pressure sensor in the FJ, but you could add one.  Randy can probably tell you where to install an oil pressure sensor, if you want an oil pressure reading.

[Alf]

Thanks, Red

Yes, I've opted for add a bit more oil. Some for the big oil filter with the Spin-on and it is clear that more oil is needed with the big cooler

But anyway the oil light flash even with the oil has been topped and accelerating hard uphill, so the sensor must not be in its best moment. I have another one from a dismantled bike, so I tried

Cheers

[Urban_Legend]

Hi Alf

With both the spin oil filter and the larger RPM cooler on my 84 1100 I add nealy .5 litre more oil. Under hard accelleration my oil light still comes on. Randy has told me that due to the placement of the level sensor, this will most likely alway happen. As long as the light goes off with normal riding then all is good. I use it as my Kookaloo light. When it comes on, I know I am having fun.

Mark

[Sparky84]

If the sight glass level is no use with spin on filter and oil cooler,

how do you know how much oil is required or in there after a bit of riding?

Cheers Alan

[FJmonkey]

If the sight glass level is no use with spin on filter and oil cooler,

how do you know how much oil is required or in there after a bit of riding?

Cheers Alan

The oil filter is not an issue if you use one with the anti-drain back feature. In fact it is better if you do, as it gets oil back to the engine parts during start up faster than having an empty filter. So you are only dealing with the extra capacity of the cooler.

[Alf]

Hi Alf

With both the spin oil filter and the larger RPM cooler on my 84 1100 I add nealy .5 litre more oil. Under hard accelleration my oil light still comes on. Randy has told me that due to the placement of the level sensor, this will most likely alway happen. As long as the light goes off with normal riding then all is good. I use it as my Kookaloo light. When it comes on, I know I am having fun.

Mark

Yes, mine do too all the time. But not my 3CV, with spin-on and bigger cooler too. So the lever sensor must be wrong

[Alf]

If the sight glass level is no use with spin on filter and oil cooler,

how do you know how much oil is required or in there after a bit of riding?

Cheers Alan

The oil filter is not an issue if you use one with the anti-drain back feature. In fact it is better if you do, as it gets oil back to the engine parts during start up faster than having an empty filter. So you are only dealing with the extra capacity of the cooler.

FJMonkey is right. In both bike with big coolers and spin-ons I add about 4 l. to reach the glass level

[ribbert]

I wouldn't get too carried away with trying to calculate the additional oil quantity. The bottom marker on any dip stick or sight glass is the correct amount of oil, between the top and bottom mark is reserve. I don't see any advantage to big filters with modern oil and fuel and the additional oil capacity of the cooler, as Red said, will not be much anyway.

The sight glass on the FJ is at the widest part of the motor and a few degrees either side of centre changes the height indicated dramatically. Leaning your bike over and satisfying yourself that if you lean it far enough the oil level becomes visible in the sight glass does not mean it's not significantly over filled.

Top to bottom on the sight glass on an FJ is quite a bit of oil and going beyond that, where it can't be measured, I would worry about over filling.

Noel

[red]

I wouldn't get too carried away with trying to calculate the additional oil quantity. The bottom marker on any dip stick or sight glass is the correct amount of oil, between the top and bottom mark is reserve. I don't see any advantage to big filters with modern oil and fuel and the additional oil capacity of the cooler, as Red said, will not be much anyway.
The sight glass on the FJ is at the widest part of the motor and a few degrees either side of centre changes the height indicated dramatically. Leaning your bike over and satisfying yourself that if you lean it far enough the oil level becomes visible in the sight glass does not mean it's not significantly over filled.
Top to bottom on the sight glass on an FJ is quite a bit of oil and going beyond that, where it can't be measured, I would worry about over filling.
Noel

Noel,

To be clear, I am suggesting that the extra capacity of the oil cooler and/or oil filter (beyond the "stock bike" amounts) should be learned, and that amount of additional oil should be added.  Leaning the bike over then will show you the top of the oil in the sight glass.  That correct leaning angle must also be learned, and not exceeded on future oil level checks, to avoid overfilling.  I realize that leaning the bike too far would invite overfilling, so the correct "lean angle" of the bike with the correct amount of oil is very important.  Without such knowledge, the oil level of the modified engine would be pure guesswork, on all future checks.

As mentioned earlier, any spin-on oil filter for the FJ should have an anti-drainback flapper valve inside, so the engine does not run without oil for some seconds, whenever it is started.  When the oil and oil filter are changed, the visible oil level will be inaccurate until the engine has run enough to fill the empty new filter with new oil.