Shift down issue...Battery issue and Temp issue...

[Brizio]

Today I drive the '89 (stock) to do some commission, the temperature outside was around 100C. After some urban traffic the temperature gauge was little over 105, went on the highway and speed up to 60mph, and the temp was still there. I check water oil and all was ok.

I went in a store and park it under the only tree left , after probably 30 minutes I came out, and it did not want turn it on, I try, try, but nothing. Luckily I had wit me a gas can, so I put some gas in the carburetor, and it started. The temperature gauge was fine too and did not moved. Drove it downtown and up in a hill I notice it will not shift down when I floor the gas pedal. When I stop, it shift first, and shift up regularly, but when I'm driving it will not shift down.

This evening I turn it on and it started right up, but the battery gauge was before the last withe bar (after this there is all red bars and 18). It never was there, usually it was below. I drove home and still it did not shift down. A the traffic light when I saw the battery gauge fluctuating, until under the 13V bar. At some point on the road the headlight was making less light, and also the battery gauge was down on the scale. But it came back up after 10 seconds, also the headlight.

I don't know if all those three are related or not, but any ideas is welcome!

[will e]

They are probably not related.

100c? That's really hot for an outside temp. Need some clarification on that.

105 engine is a little warm but not 'extreme'. How are you measuring the temps? The stock guages are known to be inaccurate.

Your alternator may be overcharging. Only way to know is to get a multimeter and check it.

[Brizio]

Sorry I meant 100F...

For the water temperature I was looking the stock gauge.

For the alternator I will check it today.

Thanks!

[DatsunTim]

As to the not starting back up when hot issue....

It is possible the fuel in your carb (or fuel line) is boiling off enough to not be able to start the engine.

We get that from time to time with the Datsuns when the fuel line is run too close to the block or the car runs too hot.

tim

[Brizio]

This weekend I check the alternator and battery and both are working fine... But I found some old wire and replace them.

I did not drive it yet. So I don't know if the problem is fixed or not.

[Achilles]

Sorry I meant 100F...

For the water temperature I was looking the stock gauge.

For the alternator I will check it today.

Thanks!

I am glad it was 100F if it was 100C it would be 212 degrees F. And I think it would be Houston we have a problem time.

[Rich88]

Today I drive the '89 (stock) to do some commission, the temperature outside was around 100C. After some urban traffic the temperature gauge was little over 105, went on the highway and speed up to 60mph, and the temp was still there. I check water oil and all was ok.

I went in a store and park it under the only tree left , after probably 30 minutes I came out, and it did not want turn it on, I try, try, but nothing. Luckily I had wit me a gas can, so I put some gas in the carburetor, and it started. The temperature gauge was fine too and did not moved. Drove it downtown and up in a hill I notice it will not shift down when I floor the gas pedal. When I stop, it shift first, and shift up regularly, but when I'm driving it will not shift down.

This evening I turn it on and it started right up, but the battery gauge was before the last withe bar (after this there is all red bars and 18). It never was there, usually it was below. I drove home and still it did not shift down. A the traffic light when I saw the battery gauge fluctuating, until under the 13V bar. At some point on the road the headlight was making less light, and also the battery gauge was down on the scale. But it came back up after 10 seconds, also the headlight.

I don't know if all those three are related or not, but any ideas is welcome!

All unrelated.

Not downshifting has nothing to do with electrical. There's a tranny linkage adjustment connected to the throttle linkage located just behind the carb. The linkage goes to the tranny. When properly adjusted the tranny will downshift to 2nd when floored, providing you're under some magic speed that I forget at the moment. 55? 50?

The temp guage reading super low is most likely due to corrosion where the temp sender plug scrunches onto the temp sender. Low resistance of the temps sender = high temp reading. High resistance of the temp sender = low reading. If you introduce corrosion then that will cause high resistance at the terminal and therefore a low guage reading.

If you did a lot of cranking before finally starting, then the alternator is going to go into max charge mode to recharge the battery. This is why the voltage read high. And it comes down as the battery charges.

Assuming you have the correct 1/2 thick spacer between the carb and the intake manifold, gas does not boil out of these 2150 carbs. This is a myth that refuses to go away. However, when very hot out you can get vapor lock, where the action of the fuel pump pulling on ethanol-laden gas can cause the gas to turn to vapor, and that's what gets pumped into the carb bowl. Only known permanent cure is going to an electric fuel pump mounted near the tank that pushes gas to the carb, guaranteeing it will always be liquid.

[Brizio]

I check few wires the yesterday, and replaced a few of them that were cooked. So the battery gauge now looks good, also when I use the turn signal it doesn't fluctuate a lot.

I will check the tranny linkage today. I hopen also this post for the transmission issue. http://www.ifsja.org/forums/vb/showthread.php?t=158699


For the gas issue it happened only that day, that was very warm.

[DatsunTim]

However, when very hot out you can get vapor lock, where the action of the fuel pump pulling on ethanol-laden gas can cause the gas to turn to vapor, and that's what gets pumped into the carb bowl. Only known permanent cure is going to an electric fuel pump mounted near the tank that pushes gas to the carb, guaranteeing it will always be liquid.

Being a NooB to FSJs, I do not know these carbs at all. I am pretty much only familiar with duel side draft SUs. And Vapor Lock is our biggest issue on the Roadsters when it is hot out and the fuel line is run incorrectly. I probably should not have said "boil off" as that not an accurate statement and I do know better.

Sorry for my NooBness
tim