What does water temp switch do?

[sblake01]

i just got done reading this and i was wondering if any of you know where to get one?

You'd have to be more specific. One what? A water temperature switch or ???? For what year car? Fuel injected (280Z-ZX) or carbed (240-260Z)? Many things were discussed in this 6 years dead thread.

[CollinH]

where can you find a water temp switch for a 75 280z

[sblake01]

Try this thread. If that is the switch you're referring to, you might even contact member saridout since he was the one that made it work:

http://www.classiczcars.com/forums/showthread.php?t=35873

[justfun13]

I'm having the same problem as well. The part 22120-N4202 is no longer available anywhere. I've talked to a couple of techs that know these cars well and suggested to plug the switch off.

The purpose of the switch is to switch between the dual points in the distributor as the car warms up. The 75 and 76 are the only cars that use this switch and was later was discontinued on the 77 and 78 280s. As mentioned in http://www.classiczcars.com/forums/s...ad.php?t=35873, you could change out to a 280zx distributor to resolve the problem. The other option is to purchase the 260z water temperature switch that MSA sells and redo the wired ends to match the 75 and 76 switch. The ends can be easily change out using a male bullet connector and insulator and a ground connector on the other terminal.

Another suggestion from techs are to use a fan switch, but you need to make sure that the switch will switch over after the car warms up past 100 degrees or less. Not sure on how accurate that would be, and if you could find a switch that would be that low on the temperature to switch, but I guess it's worth a try, plus it's lot less expensive than the MSA part.

I'm thinking of going with the MSA option and redoing the connections at this point.

[Zed Head]

I'm having the same problem as well. The part 22120-N4202 is no longer available anywhere. I've talked to a couple of techs that know these cars well and suggested to plug the switch off.

The purpose of the switch is to switch between the dual points in the distributor as the car warms up. The 75 and 76 are the only cars that use this switch and was later was discontinued on the 77 and 78 280s. As mentioned in http://www.classiczcars.com/forums/s...ad.php?t=35873, you could change out to a 280zx distributor to resolve the problem. The other option is to purchase the 260z water temperature switch that MSA sells and redo the wired ends to match the 75 and 76 switch. The ends can be easily change out using a male bullet connector and insulator and a ground connector on the other terminal.

Another suggestion from techs are to use a fan switch, but you need to make sure that the switch will switch over after the car warms up past 100 degrees or less. Not sure on how accurate that would be, and if you could find a switch that would be that low on the temperature to switch, but I guess it's worth a try, plus it's lot less expensive than the MSA part.

I'm thinking of going with the MSA option and redoing the connections at this point.

My switch was bad when I got my car, a 1976 model, and after reading through the manual and figuring out how it worked I realized that with a bad switch, the car just runs a little dirtier when it's cold. The switch advances timing when cold, I believe, to get it to run cleaner. It's only on the non-CA models.

I could be wrong on the reason to advance the timing when cold, but either way, without the switch, the car just has the timing when it's cold that it would have anyway after it warms up. My car runs fine when cold, without the switch working.

Once the car warms up, the switch doesn't do anything.

[sblake01]

The purpose of the switch is to switch between the dual points in the distributor as the car warms up. The 75 and 76 are the only cars that use this switch and was later was discontinued on the 77 and 78 280s.

The second part of that statement is true, as my 78 didn't have that switch but there were no points on any 280Z, any year as they all had electronic ignition. Read the rest of the explaination in that thread. What is says it that 260Z used a similar switch and it's function was to switch between the points. Edited May 4, 2010 by sblake01

[mn91]

So will the car run fine without.a functioning switch? Asling bthe ground wire broke on mine and I dont know if its safe yo drive without. Sorry to revive old thread

[Zedrally]

^^^

Yes, drive it by all means.

It won't fall out of the sky!

[mn91]

Sarcasm or I can really drive it? And if I do what would be different about how it performs?

[Zedrally]

Yes, you can really drive it.

In conjunction with the alternator relay (IIRC), it forms a simple logic circuit that controls the fuel pump on start up.

Originally designed to stop flooding the carbie's on a hot start.

[mn91]

Mine is a 76 efi 280 i dont have carbs? Im reffering to the temp switch. Its only on the 75 76 model...

[Zedrally]

Sorry, Can't help you.

Does it start and run?