I have a 1984 R80RT and am currently in Idaho on my way back to Michigan. The oil cooler has developed a leak. It is not losing a lot of oil yet but I am looking for a way to do an on road fix if it gets worse.
My thought is that if I replace the drilled bolts that connect the cooler lines to the thermostat with solid ones it will block the cooler flow. My question is how the thermostat works. When the thermostat is full open does is send some of the filtered oil to the cooler or all of the oil to the cooler. Is the cooler in the main oil loop or just a bypass? Is my idea OK or will it block all oil flow when the thermostat opens.
My other option would be to find a shop that can make a tube with the correct connectors and replace the cooler with the tube.
Any thoughts or comments are appreciated
You're in luck. I just spent all of last month figuring out how the thermostat works because mine was not working.
All the oil circulates into the aluminum housing on the side of the engine. There a thermostat senses the oil temperature. When the oil temperature reaches a certain level, a small pin comes out of the thermostat base and starts to move the oil flow shuttle. Shuttle movement is opposed by a large spring on the opposite side of the housing. The default oil flow shuttle position is "no oil cooler".
The shuttle "fit" inside the housing is not oil tight, but MOST of the oil flow is directed, either to or away from the oil cooler. The thermostat is of the bi-metal type, so it is infinitely variable between "open" and "closed", and is only "wide open" (all oil cooler) at the hottest temperatures.
► The oil naturally wants to follow the path of least resistance, which is not through the oil cooler. If the cooler were removed without blocking the hose ends, lots of oil would be lost because the open hoses would instantly become a path of lower resistance.
► Yet the hose ends cannot simply be capped because when hot, most of the oil is re-directed to that path. To cap the 2 hoses, one would also have to remove the spring, shuttle, and thermostat in order to assure themselves of amble oil to the engine bearings.
► Having something connect the 2 hose ends (either a loop or another cooler) is the best solution. However, finding metric fittings to make a loop is going to be a tall order. IMHO, you had better have a friend over-night you their oil cooler. Might be time to break out the Airhead membership list !
An R100 definitely cannot run without the cooler due to the small oil supply. It is not clear to me if an R80 fits into that category or not. Obviously, ambient temperature and humidity would play a VERY large part in determining the outcome. The very best "no oil cooler" scenario would be riding in the rain, with the front wheel delivering lots of water to the bottom side of the oil pan.
Hope this helps and best of luck.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Thanks
Fortune is with me. I contacted an Airhead member from the AirDirectory that had an oil cooler in his parts supple. That cooler is now on my R80RT.
Wow! You are extremely fortunate.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
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