[C1] Temp Issue
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Joined: Feb 2014
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Temp Issue
Ok, I have a strange one.. Just took my 62 for its first ride since I restored it. Temp gauge rises when I accelerate, then goes back down when I slow down. I checked the temp with a heat gun and its running at normal temp, so it does not appear the be running hot. What could be causing this? Could it be a ground issue?
Any suggestions would be appreciated,
Thanks,
Mark
Any suggestions would be appreciated,
Thanks,
Mark
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From: Camp Verde AZ
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Possibly, or bad battery connections. Do any other gauges rise and fall? If not, it proably isn't electrical
Are you running an alternator or generator?
You don't say how much it rises.
Doug
Are you running an alternator or generator?
You don't say how much it rises.
Doug
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Hello Doug,
Just the battery gauge but it's just charging I believe. Checked battery connections, clean and tight. I'm running a generator. When I accelerate temp gauge rises quickly to full, then at idle its normal. When I place a infrared gun to the head and raise the rpms, it stays between 168 and 171 deg.
Thanks, Mark
Just the battery gauge but it's just charging I believe. Checked battery connections, clean and tight. I'm running a generator. When I accelerate temp gauge rises quickly to full, then at idle its normal. When I place a infrared gun to the head and raise the rpms, it stays between 168 and 171 deg.
Thanks, Mark
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Disconnect the temp gauge at the temp sender and see what happens. Does the gauge still rise?
Is the harness ground to the engine connected? it should connect at either a valve cover bolt, or maybe the coil bracket, IIRC.
Doug
Is the harness ground to the engine connected? it should connect at either a valve cover bolt, or maybe the coil bracket, IIRC.
Doug
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Doug,
I tested it again with the infrared gun. This time I pointed it directly at the sending unit. This does show the temp rising to about 220 Deg when I increase the rpms by manually moving the throttle linkage..
I tested it again with the infrared gun. This time I pointed it directly at the sending unit. This does show the temp rising to about 220 Deg when I increase the rpms by manually moving the throttle linkage..
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I had the same exact problem with my temperature gauge in my 57 . The gauge was saying over 200 and the infared heat gauge was showing normal around 170 .I just replaced them with Auto Meter " Old Tyme " 2 1/16 gauges from Summit for the temp and gas gauges . The temp gauge comes with the correct sender and it works great . The gas and temp gauges are totally accurate now . I'm going to order the matching gauges for the oil and charging gauge . All of the gauges are a direct fit .
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Doug,
When I disconnect the temp sender gauge is off.. I have the harness grounds connected to each valve cover bolt. With engine at operating temp at idle, infrared gun reads about 170Deg. When I increase rpm's it seams to max out at 215 Deg.
Mark
When I disconnect the temp sender gauge is off.. I have the harness grounds connected to each valve cover bolt. With engine at operating temp at idle, infrared gun reads about 170Deg. When I increase rpm's it seams to max out at 215 Deg.
Mark
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just some thoughts:
- is the temp gauge sender going too far into the head and almost touching / bottoming out on the sensor-head
- is there an air pocket in the sensor area
- poor water flow when the engine is idling (allowing a hot spot in the engine) - drill a 1/16 - 3/32 hole in the thermostat to keep it flowing while the stat is closed. ( this will not affect the operation of the stat.)
- relocate the temp sender to the intake manifold and note if there is a greater / less change
- pump is caveating when the motor revs
- return hose is collapsing when the motor revs and the pump pulls more water from the rad
- incorrect temp sending unit
If it's the gauge - could be overvoltage from the generator.
- is the temp gauge sender going too far into the head and almost touching / bottoming out on the sensor-head
- is there an air pocket in the sensor area
- poor water flow when the engine is idling (allowing a hot spot in the engine) - drill a 1/16 - 3/32 hole in the thermostat to keep it flowing while the stat is closed. ( this will not affect the operation of the stat.)
- relocate the temp sender to the intake manifold and note if there is a greater / less change
- pump is caveating when the motor revs
- return hose is collapsing when the motor revs and the pump pulls more water from the rad
- incorrect temp sending unit
If it's the gauge - could be overvoltage from the generator.
Last edited by BLUE1972; Oct 22, 2018 at 04:30 PM.
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From: Camp Verde AZ
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Where is the sending unit, in the head?
I always use manifold mounting locations.
If your IR guns reads 215 at the sending unit and the gauge reads the same, well, you know it is correct. IMO, head mounted sending units are only good for idiot light senders.
Doug
I always use manifold mounting locations.
If your IR guns reads 215 at the sending unit and the gauge reads the same, well, you know it is correct. IMO, head mounted sending units are only good for idiot light senders.
Doug
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This caught my eye too.. If your regulator is not working, it may be stuck in 'charge' mode.. so when you rev the motor, you're getting a very high voltage in the system, causing the gauges to fluctuate.
Does the fuel gauge move around at the same time?
Or, if you have a volt meter, check the voltage when revving.
Does the fuel gauge move around at the same time?
Or, if you have a volt meter, check the voltage when revving.
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From: Cottonwood AZ
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I had the same exact problem with my temperature gauge in my 57 . The gauge was saying over 200 and the infared heat gauge was showing normal around 170 .I just replaced them with Auto Meter " Old Tyme " 2 1/16 gauges from Summit for the temp and gas gauges . The temp gauge comes with the correct sender and it works great . The gas and temp gauges are totally accurate now . I'm going to order the matching gauges for the oil and charging gauge . All of the gauges are a direct fit .
I replaced my tach with an Auto Meter unit that fits the "can" and was able to use my original needle.
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Ok, I may have a over heating issue. I pulled the thermostat and running without one at the moment. When the car is at idle it runs about 180 deg. As soon as I start to rev the motor, it goes up quickly. I measured the temp with an IR gun at the temp sending unit. It tracks fairly close to the gauge (all gauges are original), At Idle, its 178 to 180, then as soon as I start the rev the motor it climbs quickly. It got to 226 deg on IR gun in less than a minute.
Perplexed,
Mark
Perplexed,
Mark