Ottertstat connection question

[Timebender]

Hi guys,
I'm trying to find out how the otterstat is supposed to be hooked up. Mine works, fans come on at 220 (according to my gauge), and I see where it's connected at the bulkhead on the top left white connector. The other tab on it (because of the engine conversion) goes to the electric choke on the carb and that itself is grounded to the carb body (it's a Holley carb). Because of this, the choke has never really worked, as it doesn't seem to be getting a constant 12 volts on ignition in order to warm up the spring and open the choke - in fact as long as I've had the car, the choke has always been stuck part way open and closed.

So I'm thinking about running a wire from the hot on ignition line at the bulkhead to the choke (getting a new cap or even a whole new carb as mine is just too complicated, and needs a rebuild too), and then running the wire that's now connected to the choke to ground somewhere.

Am I correct in assuming that there really is no voltage passing through the otterstat until it hits a certain temp, thus closing the switch, which then turns on the fans? Which also means the choke won't get any power until the car gets hot enough?

Greg

[BABIS]

Hi guys,
I'm trying to find out how the otterstat is supposed to be hooked up. Mine works, fans come on at 220 (according to my gauge), and I see where it's connected at the bulkhead on the top left white connector. The other tab on it (because of the engine conversion) goes to the electric choke on the carb and that itself is grounded to the carb body (it's a Holley carb). Because of this, the choke has never really worked, as it doesn't seem to be getting a constant 12 volts on ignition in order to warm up the spring and open the choke - in fact as long as I've had the car, the choke has always been stuck part way open and closed.

So I'm thinking about running a wire from the hot on ignition line at the bulkhead to the choke (getting a new cap or even a whole new carb as mine is just too complicated, and needs a rebuild too), and then running the wire that's now connected to the choke to ground somewhere.

Am I correct in assuming that there really is no voltage passing through the otterstat until it hits a certain temp, thus closing the switch, which then turns on the fans? Which also means the choke won't get any power until the car gets hot enough?

Greg

in the original set up the otterstat is fed by fuse 5 (power on the first click of the key) and the signal goes through pins 2 (return, black orange wire) and 4 (from the fuse, green) of the yellow engine connector..

[Timebender]

in the original set up the otterstat is fed by fuse 5 (power on the first click of the key) and the signal goes through pins 2 (return, black orange wire) and 4 (from the fuse, green) of the yellow engine connector..

I was taking a look at the bulkhead diagram and noticed that. I can't imagine how it could be working hooked up to no power or return dead-ending at the choke - so most likely I was tracing the wire from the choke and lost that trace near the otterstat, assuming it was the same wire, as the fans do work.

I'll track it again when I get home or this weekend to double check.

[sdg3205]

Am I correct in assuming that there really is no voltage passing through the otterstat until it hits a certain temp, thus closing the switch, which then turns on the fans? Which also means the choke won't get any power until the car gets hot enough?

Greg

Yes, you're right. You'd have no choke unless your engine was at or above the threshold of the otterstat.

[David T]

Yes, you're right. You'd have no choke unless your engine was at or above the threshold of the otterstat.

Another good place to get the power would be if you can find the plug that went to the Control Pressure Regulator. It powered a heating element inside and was also switched on and off by ignition power. Should have enough power for your choke heater. Test your choke heater by temporarily running power and ground to it directly. Most of those heaters were internally grounded, only needing 1 wire, the power. Power was to help open the choke early, it should still open if you can find a heat source to attach it to. You should not rely only on electric power to open the choke.

[Bitsyncmaster]

Another good place to get the power would be if you can find the plug that went to the Control Pressure Regulator. It powered a heating element inside and was also switched on and off by ignition power. Should have enough power for your choke heater. Test your choke heater by temporarily running power and ground to it directly. Most of those heaters were internally grounded, only needing 1 wire, the power. Power was to help open the choke early, it should still open if you can find a heat source to attach it to. You should not rely only on electric power to open the choke.

The power for the CPR is from the RPM relay so only on when engine is running (in stock wiring).

[Timebender]

I looked at my wiring- both wires are where they need to be at the bulkhead for the otterstat. Then a wire is alos coming off #2 spliced in that goes to the electric choke.
So if I take that wire from the choke and run it to some place on the engine, it will cause the choke to open? I had always assumed it was a 12 volt source that heated up the spring inside.

[Timebender]

I did find out that the wire coming off #2 has one going to the otterstat, and another going off tot the choke, which is putting out 12 volts.
I spayed some carb cleaner int to the carb, and not the choke is working as expected.