Running Hot, Gauge, Wire, Sending Unit??? Which is it?

[PsRumors]

Here is what I have '85 K20 Burb with a newly transplanted 454, got it running today.

Temp Gauge is showing at the line between 210 & 260. Replaced the sending unit and got the same thing. The gauge does rise and fall but is just high.

If my notes I have are correct the following ohm values correspond to the temp.

210* - 185 ohms
160* - 450
100* - 1800

I put the ohm meter on the sending unit and am reading between 220 and 240 ohms. I am running a 180* thermostat.

Anyone with experience?

I want to use the stock gauges cuz that is what I like. It was working prior to the engine change.

Thoughts?

 

[mr.smartass]

Umm I don't know maybe the motor is running hot... It's the only thing you changed right? Just something to look into.

 

[PsRumors]

Yup....a possibility but I dont think it is. If you look at the ohms I pulled off the sensor it doesn't appear too. Do you have any experience with the ohms value of the sending unit? I am wondering if my values are correct.

It doesn't seem the engine is running hot. The coolant temp in the radiator about 10" below the filler neck is at 170*.

 

[mr.smartass]

nope no experience with the ohms... What motor came stock in the burb? Is the sending unit the same as the one that came with the stock burb?

 

[PsRumors]

It was a 350. I haven't checked to see if the sending units were the same....good catch.

 

[dyeager535]

I believe the reistance should be 0-90 ohms, (full sweep of gauge) make sure you've got good contacts, and good wires on your tester.

 

[BlaKK54Speed]

its all in the "ohmage" make sure the sending unit is designed for that kind of gauge

 

[diesel4me]

one thought..

Did ya swap in a big block radiator to go with the 454??...a small block one may not be big enough,and will make it run hot!...

 

[PsRumors]

I did swap in a new radiator but all of them have the same part #.

I do believe though it is the sending unit. Just haven't had a chance to work on it.

 

[3 on the tree]

Two ideas;

Ground the sending unit wire, with the gauges on. The gauge should read full sweep right, at least every one I've ever tried has.

Are you sure you got ALL the air bubbles out of the cooling system? A large air bubble will do all kinds of weird things.

 

[PsRumors]

Two ideas;

Ground the sending unit wire, with the gauges on. The gauge should read full sweep right, at least every one I've ever tried has.

Are you sure you got ALL the air bubbles out of the cooling system? A large air bubble will do all kinds of weird things.

Grounded it sweeps full hot.

I believe I have a sensor issue. I just haven't had any more time to work on it.