Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Engine oil temperature

I am not sure if the oil temperature of the engine is sometimes a little bit to high. Has anyone measured the temperature ?
Who has new experience with an oil cooler for the S&S.

Thanks
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Player

Obviously not having one, I cannot fully answer.

However, air cooled engines often run a bit hotter than water cooled ones*. My understanding is S&S recommend a Mobil 1 oil, and when I last looked into oils, Mobil 1 could be subjected to higher temperatures than anything else without going out of grade.

* Piston manufacturers often recommend greater clearances for air cooled engines for that reason.

|I have fitted a combined engine oil pressure and temperature gauge to my M3W with the following results.

Start up from cold:-
Temperature of oil is the same as the ambient air temperature (as you would expect).
Oil pressure at tick over is around 60 to 70 psi. and only goes slightly over that when the engine is revved. I dont know if there is some form of pressure relief valve that limits the upper oil pressure.

Normal running:-
Temperature of oil normally between 75°C and 85°C (obviously again dependant on ambient air tremperature).
At this temperature the oil pressure at around 3000 rpm is 50 to 55 psi. At tick over this drops to approximately 25 psi.

Stuck in traffic:-
I have seen the oil temperature go as high as 112°C but skip fire has still not cut in.
At this temperature the oil pressure goes down to around 17 to 22 psi. at tick over and 40 to 45 psi at around 3000 rpm.

I don't know if mine is typical but I hope this is of some help.

Keith

I have stuck cheap thermocouples attached to both the under bonnet oil tank and directly to the bevel box casing , with trailing leads to simple digital readouts in the cockpit

My findings for the engine are completely agree with KBMOG above , and dont hold to much concern.
For peace of mind I fitted a slip on cooler to the oil filter , similar to this
http://www.ebay.co.uk/itm/Slip-On-Oil-Cooler-WITH-MAGNET-HARLEY-INDIAN-USA-MC-/291600615614?hash=item43e4c048be:g:TDMAAOxyCGNTOhK1
Diffcult to say how effective it is tucked away under the engine as it is , but it has to help. I also like the magnet to trap stuff in the oil filter.

The bevel box is a different story, running much hotter , and close to the max limit for the oil I was using so changed to Redline which has a higher temp range .I believe it runs too hot for the job its doing. Sorry dont have the figures to hand , but in normal driving it is constantly approaching 100c
and regularly peaks 120c. Been thinking about a separate radiator circuit , which I think has been mentioend recently on here.For me too complex / too many failure points.
Or simple ducting to get a proper air flow over it ( aesthetics may have to be put on hold ! ).

Hope this helps

Airflow over the bevel box may be the issue, it is only passively oil/air cooled. A standard differential hangs under the car in the airflow. How much air can the bevelbox be getting, seeing as its tucked up and boxed in? Maybe just an aluminum diverter underneath to scoop air up and over the casing? Or cooling fins cast into the casing?

Http://www.hks-power.co.jp%2Fen%2Fproduct%2Fcooling%2Fdiff%2Findex.html

I have thought about cooling the oil on this beast but after long consultations with a local S&S mechanic we determined that it would be overkill. Mind now, I live in southern Vermont with no large cities and miles of roads devoid of traffic lights as well as having very temperate weather during driving season.

The other issue is that you are carrying 6 quarts of oil versus the standard 4 quarts on any bike. That helps in a large part. It also gives you more latitude between oil changes.

I have changed out the oil since the very beginning and it still looks and feels great after 3,000, 4,000 and 5,000 miles. It does get pricey as the oil universally recommended is the Mobil Synthetic for V-Twins. Good stuff.

If you are due for a service then please ask your dealer to see the engine diagnostic. It will show you temps, rpm's used as well as many other things of interest. What I learned from mine was that there were occasional spikes of heat as well as revving the motor hard but, for the most part, in actual use this car is loafing along.

A cheap ram air cooler for the bevel box.

Am I right thinking yours doesnt have the NVH Dab ?

Nah, no namby pamby nvh on my ride, rigid is where it's at.