Remote oil thermostat

[jrthomas]

Are most of you running the oil thermostat? I can't seem to find any information on purging the system with the thermostat. It seems to me that the thermostat redirects the flow through the oil cooler when the temp reaches a certain level and by purging a cold engine, the oil cooler is being bypassed. I had a small leak on one of my oil cooler fittings and may have allowed some air in. I need to purge but I want to make sure I do it right. Thanks, James Thomas

[Paul Z]

All of the new SLSA use oil thermostats, mine didn't come with one, but John has said I could add one when I do the 5 year hose replacement. I'd need to go read the instructions to better understand how they work. They mount them behind the engine on the lower engine mount tubes. I do have some photos of the installation if interested, and I also have the installation instructions. I could make a PDF of the installation instructions as well.

[jiott]

Kitfox sells an oil thermostat kit with all the hoses and fittings you need, as well as instructions.

I purged my oil system just the way Rotax says to do it and had no trouble because of the oil thermostat. I believe the thermostat never totally blocks off the oil cooler, so when you purge you will move some oil thru the cooler.

[Dorsal]

My experience is the same a Jim's, I have a thermostat and use the normal purge procedure.

[jrthomas]

I suspected, based on the lack of any info otherwise, that the purging process would be the same. The oil thermostat I have is the same one that Spruce sells, (#15-05849). Their info says it remains 10% open so, hopefully, purging will displace any air that I might have let into the oil cooler. Thanks again, James Thomas

[Slyfox]

crank the engine with the mags off. if you have oil pressure you are purged. you can also do the prop turning until it gurgles in the tank. the oil thermostat works by bypassing the cooler, same thing as going through the cooler. when it gets hot it allows passage through the cooler. not an issue for purging air at all. the air doesn't know the thermostat is there.

[jiott]

I'll have to disagree with every point you make:

1. You do not have a successful purge until you have oil pressure AND solid valve lifters.
2. A gurgle in the tank only means you have pushed all the oil out of the crankcase; it does not mean you have purged all the air out of the oil system.
3. Air trapped in the oil cooler must get purged out or when the thermostat opens you will get a slug of air into the system-not good. Fortunately the 10% going thru the cooler even with a closed thermostat will purge the air out of the cooler if you give it enough time. Therefore it is somewhat of an issue in purging.

[Paul Z]

You need to purge the system with pressure. There is a pressure line to put on the oil return side of the oil tank to push oil from the tank to and through the engine to purge the air from the engine, oil cooler, oil thermostate, and the oil lines. You need to get all of the air out. At the Rotax Maintenance Training class, the taught us that anytime you change lines, or remove the oil tank. The system needs pressurized to push oil through the system, and purge the air from the system.

[TahoeTim]

Do we have two conversations going on here?

It seems like some of you are discussing purging after installing the kit and some of you are talking about pre-flight burping of the crankcase.

[Slyfox]

I stand behind what I said. the question was opening a line and have some air. If you are starting a new engine, that requires much more. you have air in your cooler it goes out real fast when the thermostat opens. I never worried about that. I have my new engine at 500hrs and the old one went about 2200hrs. never an issue and yes I have the lockwood thermostat, have had it forever on both engines. I also believe the air in the cooler goes right into the tank not the engine on flow. correct me if I'm wrong. still I've never had an issue with this. If there is air in the system, the oil pressure will be none. this is for sure.