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DISCUSSION => Engine + Driveline => Topic started by: n2motorsports on February 20, 2012, 04:45:41 PM

Title: quick thermostat question
Post by: n2motorsports on February 20, 2012, 04:45:41 PM

facts:

-temp gauge isn't working
-installed a new water pump and thermo several months ago and car just sat
-can't bleed system, not taking in much coolant as i let it idle on an incline even after a spirited drive
-heater works
-lower radiator hose is cold

replace thermostat?

Title: quick thermostat question
Post by: DesktopDave on February 20, 2012, 04:52:47 PM

If the heater is working it's likely pretty close to OK.  Hard to tell without the temp gauge.  Can you borrow an IR thermometer to see what's really going on?

Try to bleed it on an incline.  Check the rear temp sender in the head for a loose connection.  Might be the cluster too, the little rear nut has a habit of working loose.

There's a bleeder passage on the thermostat housing...did you use silicone or the OEM paper gasket?

Title: quick thermostat question
Post by: n2motorsports on February 20, 2012, 07:06:16 PM

thanks Dave.  i'm gonna try to eliminate the easy stuff first.  i believe that you can jump the temp sensor harness to create a "high temp" and see if the needles move.  if it doesn't gauge is dead and i'll pull the dash...urrrgg.

Title: quick thermostat question
Post by: danlolasdad on February 21, 2012, 02:08:16 AM

Quote from: n2motorsports;110441

thanks Dave.  i'm gonna try to eliminate the easy stuff first.  i believe that you can jump the temp sensor harness to create a "high temp" and see if the needles move.  if it doesn't gauge is dead and i'll pull the dash...urrrgg.

correct about if the gauge doesnt move change dash cluster but that can also mean its the wiring to gauge

Title: quick thermostat question
Post by: n2motorsports on February 22, 2012, 06:05:36 PM

Done.  Gauge works, so now the temp sensor and thermostat will be replaced.

Title: quick thermostat question
Post by: n2motorsports on February 29, 2012, 01:43:40 PM

Replaced both sensors.  Gauge isn't working.  Time to pull the dash....hating this car right about now.

Title: quick thermostat question
Post by: DesktopDave on February 29, 2012, 02:24:04 PM

It's always the easy stuff...unless the easy stuff is hard.

I don't like pulling the dash either.  Might be a bad driver board as well...I have a cluster with one single burned trace on that board.  Killed half the dash.

Title: quick thermostat question
Post by: n2motorsports on March 14, 2012, 02:32:34 PM

Quote from: DesktopDave;110427

If the heater is working it's likely pretty close to OK.  Hard to tell without the temp gauge.  Can you borrow an IR thermometer to see what's really going on?

Working at a restaurant finally paid off, borrowed the IR thermo reader and got this:

top radiator hose:  177 F
lower hose:           145F

What's normal for our cars?  btw, that was after 30 mins of combined city/hwy driving.  Temp gauge is still pinned to the left, with ignition "ON" it'll pin itself to the right.