SOHC temp gauge vs DOHC temp gauge

[Ritz S14]

Ok. First of all, I have a '90 240sx with a full aluminum koyo radiator. My cluster is a SOHC, but I have the DOHC tach installed to keep the uber high milage. The motor is a 95 KA, with a 93 coolant temp sensor. My gauge only climbs up to a 1/8-1/4 high at most. Is this the work of a the radiator? Or mismatched gauge + temp sensor? OR is it because I'm STILL running a clutch fan?

Any ideas?

Thanks.

[g6civcx]

The OEM temp gauge is not accurate. Get a good aftermarket one.

The stock one only read, low, med, and hi. If it starts moving up you're already overheating.

[Ritz S14]

Yeah. But it never reads medium, that's the thing. I do plan on getting an aftermarket gauge though.

[g6civcx]

I wouldn't sweat it. Either the sending unit is broken or the gauge itself is malfunctioning. Replace the sending unit and see, or swap gauge clusters with a known good and see.

[Ritz S14]

I've swapped the sending unit, still same problem. The gauge worked before the motor was swapped over. BUT, I've also added a new thermostat and heavy duty radiator, water wetter, and retained the stock clutch fan. I even covered a 1/4 of the radiator with cardboard, no change. Driving 60mph for about 20 min, only 1/8 high. I'll see if swapping over to a DOHC cluster would help.

Thanks..

[g6civcx]

Okay, take it to a good shop. What they'll do is stick a temp sensor into the radiator and measure coolant temperature. Shouldn't cost much if any money to do it.

Normal operating temperature should be around 200F somewhere.

[Ritz S14]

Once I replace the battery in my DVOM, I'll compare the specs to the FSM. Should have just went that route haha, but it hasn't been my priority.

Thanks for the tips.