Finding alternative to otterstat

Has anyone replaced their otterstat with an alternative? After finding out how many of them simply don't work, I've been thinking of having a 3/8" npt adapter welded into the hole for the stock otterstat. this make it possible to use a bunch of non-specific fan switches like this https://m.summitracing.com/parts/der-16731#

I haven't spec'd out a switch with the same on/off temps as stock yet. I'm assuming this should function without modifying the stock wiring though.

This is what I want to do. I might just get it if it's npt and not bspt. http://www.deloreanclub.uk/new-style...otterstat.html

Toby has an alternative but current NA.

http://www.delorean-parts.com/Mercha...t_Code=K4002DP

Maybe I should start a new project with an electronic unit. I could eliminate the hysteresis (most of it caused by mechanical switches) so the temp gauge would not over and under shoot. But when the AC is running (most of the time for me) the otterstat is not even used.

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Has anyone replaced their otterstat with an alternative? After finding out how many of them simply don't work, I've been thinking of having a 3/8" npt adapter welded into the hole for the stock otterstat. this make it possible to use a bunch of non-specific fan switches like this https://m.summitracing.com/parts/der-16731#

I haven't spec'd out a switch with the same on/off temps as stock yet. I'm assuming this should function without modifying the stock wiring though.

This is what I want to do. I might just get it if it's npt and not bspt. http://www.deloreanclub.uk/new-style...otterstat.html

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These were in part developed by our own club historian Chris Parnham, I had one of the first and have had no issues since fitting it two years or so ago. Much better than the three otterstats I went through in 3 months!
Chris

The adjustable fan switch that Toby has been selling is a great replacement to the otterstat. Two of my buddies have installed them as well. We even had a new straight aluminum pipe made that replaces the original where the otterstat went. I didn't want to deal with a pipe that might leak. My otterstat developed a crack in the brass housing, so I just eliminated it all together. Whenever they come back into stock I would pick one up.

Its not a bad idea. On my Opel GT I decided to add an electric fan and it is controlled by this:
https://www.amazon.com/Hayden-Automo...ic+fan+control

Granted this ^ unit doesn't actually go into the coolant, it's literally just a probe you stick into the fins of your radiator. Still, with the turn of a dial, you can set when you want the fans to come on. I just let the car heat up until my temp gauge was at a point that I wanted them to turn on, went to the dial and rotated it slowly until it kicked on the fans. Haven't had to touch it since and it works perfectly. They'll cycle on if I sit in traffic too long, but then cycle off again once it cools dow.

Like I said, the one I use on that car probes into the radiator fins, but it looks like this one is designed such that the probe goes into a coolant pipe:
https://www.amazon.com/Hayden-Automo...ic+fan+control

Looks like it'd be pretty darn easy to setup.

The otterstadt switch is nothing special as far as controlling the fans. Any switch that can sense temperature and make a break the circuit can work. The "Magic" comes in when you have to pick the temperature that the circuit makes at and breaks at. It must work in conjunction with the thermostat in the motor. It's on and off points must be far enough apart so the fans are not starting and stopping too often. You can find those points by experimentation, testing a known, good otterstadt switch or by calculation. Having an adjustable switch is not the best thing since it can be changed. Once you get the right set points there should be no need to ever adjust the switch. A surface mounted switch can work, the setpoints may just be a little different. As with any modification, the vendors will no longer be able to support you so you must document all of the parts so if you ever need to service it you know where and what to get.

I can't find anything on the thermostat open temp, but saw the otterstat listed at 210/206 on and 190/195 off. From what I read thermostat is 180, I did see one that was 195on and 185 off

The thermostat itself has more to do with the rate at which the engine heats up, rather than the temperature the engine reaches. All it does is determine at what temperature it will allow coolant to start flowing, but once it opens, thats it; it has no other involvement and it shouldn't ever close again while the engine is running.

If you want your engine to warm up slower, put in a lower thermostat like a 160; if you want it to warm up faster put in a 190. Neither one of these will affect the maximum temperature the engine will actually reach, it will only affect how quickly that temperature is reached once the engine is started.

In high school, one of my friends swore that it was best to have coolant flow immediately to keep your engine as cool as possible, so he removed the thermostat from his S10. It took forever for his engine to heat up. This wasn't quite as big of a deal in the summers, but in the winter, you want your engine to come up to temperature as excessively cold parts can wear at a higher rate. Not to mention it would take him like 20-30 minutes to get heat in the winter, haha.

The rate at which the motor will warm up is a function of how much heat the motor generates over time. Once it hits the opening temperature of the thermostat it opens. Depending on ambient temperature the thermostat may cycle closed and open to keep the motor at operating temperature. Ideally you want the rad to be able to dissipate more heat than the motor can generate under all operating conditions and let the thermostat maintain a constant operating temp by opening and closing. You want the motor to be at operating temp as quickly as possible because it is most efficient at operating temp. All of the clearances (rings, piston, valves, etc) are designed to be at operating temp. Above operating temp the clearances are not enough and below they are too big.