Water temp/battery gauge problem
Thread Starter
Intermediate
Joined: Jul 2007
Posts: 40
Likes: 0
From: Brownstown Michigan
Water temp/battery gauge problem
Just replaced new water temperature, oil pressure and ammeter gauge on my 70 roadster. I also replaced the coolant temperature sensor. I have a new heavy duty all aluminum radiator and a fixed flex fan. However, the gauge temperature reading is somewhere 140-150. Am I reading this correctly? or something is wrong. What is the other sensor with two prongs on the passenger side with green wire in addition to the coolant temp. sensor on the driver side head?
The oil pressure gauge is reading between 35-40 PSI. Am I also reading this correctly?
The battery gauge is reading 0-5, is this correct?
Are there ways to test the gauges for operation before installation?
Any suggestions is greatly appreciated.
The oil pressure gauge is reading between 35-40 PSI. Am I also reading this correctly?
The battery gauge is reading 0-5, is this correct?
Are there ways to test the gauges for operation before installation?
Any suggestions is greatly appreciated.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
What temp thermostat do you have installed? {or was that left out when you put in the new radiator} I also don't understand the ammeter reading of "0-5". What does that mean? A good ammeter reading should be near zero after the car has run long enough to have the battery fully charged. To test the ammeter (in the car), turn on headlights [ignition OFF]; the ammeter should read somewhere around 5 to 10 amp discharge. You can bench test all the instruments...if you have the correct equipment. You would need a volt-ohmeter, a 50 watt/2 ohm resistor, and the correct procedures to do so.
Thread Starter
Intermediate
Joined: Jul 2007
Posts: 40
Likes: 0
From: Brownstown Michigan
7T1vette, you are absolutely correct. My amp gage was reading zero and I thought zero reading was faulty, but there is really nothing wrong with my amp meter. Thanks for clarifying.
I put a 180 degrees thermostat and it seems as my temp gage does not want to go past 140-150. Could my car be running cool is there something wrong?
I put a 180 degrees thermostat and it seems as my temp gage does not want to go past 140-150. Could my car be running cool is there something wrong?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
I'm thinking that the engine temp is probably around 180 and your gauge just reads low. That could be due to not having the correct temp sender, or having corrosion or ???? preventing good contact between sender threads and the block, or gauge calibration being 'off'.
Le Mans Master
Joined: Aug 2006
Posts: 7,423
Likes: 1,558
From: mount holly NC
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As stated by 7T1vette the temperature sensor (on the left head) works off resistance, many of the aftermarket ones are not calibrated correctly, that could be why your gauge is off. Try another vendor.
The sender on the right head was for TCS- transmission controled spark, which was part on the emissions deal at the time.
Your thermostat is just fine, a Robert Shaw #330-180 or Mr. gasket # 4364 has holes in it so water still flows if it fails, so next time that might be a better choice. PG.
The sender on the right head was for TCS- transmission controled spark, which was part on the emissions deal at the time.
Your thermostat is just fine, a Robert Shaw #330-180 or Mr. gasket # 4364 has holes in it so water still flows if it fails, so next time that might be a better choice. PG.
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Racer
Joined: Apr 2007
Posts: 360
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Don't use any teflon tape or sealer. Just make sure the edges are true, and both the sender and the block are flat. The pressure you put on it to tighten it, will make the necessary seal. 
The tape and sealers could disrupt the ground too.
The tape and sealers could disrupt the ground too.
