Temp Sender
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Joined: Apr 2002
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From: Worcester MA
Temp Sender
I looks like I have two temp senders, 1 in the block and 1 in the head. One of which is a single terminal and the other is a double terminal. Which one of these does what? Why do I have two?
My car is a 74 SB.
My car is a 74 SB.
Melting Slicks
Joined: Jan 2000
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From: far, far away
Re: Temp Sender (schrecke)
Where in the block? If it's just above the oil filter, that's the usual location for the oil pressure sender. Not sure what year those were changed from mechanical to electric, tho. If it's on the upper surface at the back of the block, under the distributor, that is also oil pressure. However, either of those could be an oil temperature sender, although that was not a factory item until the '81 model.
The one in the head is definitely a coolant temperature sensor, although it could be either a sending unit for the temp gauge, or it could be a thermal switch for an auxiliary electric fan. On later C3's, like my '81, there's a one-wire sender in the d.side head for the temp gauge, and a two-wire sensor in the p.side head for the auxiliary fan.
[Modified by Gator81, 3:01 PM 5/21/2003]
The one in the head is definitely a coolant temperature sensor, although it could be either a sending unit for the temp gauge, or it could be a thermal switch for an auxiliary electric fan. On later C3's, like my '81, there's a one-wire sender in the d.side head for the temp gauge, and a two-wire sensor in the p.side head for the auxiliary fan.
[Modified by Gator81, 3:01 PM 5/21/2003]
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Joined: Apr 2002
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From: Worcester MA
Re: Temp Sender (Gator81)
The oil pressure sender was on the driver side of the block. I have already identified that one. One of the senders I asked about came from the passenger side of the block, and the other one came from one of the heads (I can't remember which side without looking). I have no auxillary fans or any of that.
Safety Car
Joined: Jun 2001
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From: Severna Park Md
Re: Temp Sender (schrecke)
The one in the head with one connector is for the temp gauge. The one in the passenger side block with two connectors is for TCS. Transmission Controlled Spark. TCS is a sys designed to retard timing in high gear to make cleaner emissions I think. I would dis-connect and dis-regaurd the TCS sender.
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From: Worcester MA
Re: Temp Sender (Jvette73)
I just found this definition of TCS:
transmission controlled spark (TCS): An emissions-control system to prevent distributor vacuum advance at normal operating temperature until the transmission has shifted into high gear by using a transmission-mounted electric switch controlling a solenoid-actuated vacuum valve.
The piece I'm talking about looks to just be a temp sensor, so there must be more pieces to this TCS thing in the transmission?
Do most people on here disconnect this thing?
transmission controlled spark (TCS): An emissions-control system to prevent distributor vacuum advance at normal operating temperature until the transmission has shifted into high gear by using a transmission-mounted electric switch controlling a solenoid-actuated vacuum valve.
The piece I'm talking about looks to just be a temp sensor, so there must be more pieces to this TCS thing in the transmission?
Do most people on here disconnect this thing?
Drifting
Joined: Nov 2000
Posts: 1,390
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From: North Brunswick NJ
Re: Temp Sender (schrecke)
The temp sensor in the head on the drivers side with the 2 prongs is for the TCS system. This sensor will cause the vacuum advance to operated during cold start ups and high temp [220 f].
The system has 3 main units. The temp sensor, the sensor on the trans and the TCS solinoid. The trans sensor will indicated which gears will allow the the vacuum advance to operate, usually 4 gear [depends on the year]. The solinoid [atached to the intake manifold next to the carb] is the connection of the vacuum lines to the vacuum advance and is switched on and off from the gears in the trans.
Ed
The system has 3 main units. The temp sensor, the sensor on the trans and the TCS solinoid. The trans sensor will indicated which gears will allow the the vacuum advance to operate, usually 4 gear [depends on the year]. The solinoid [atached to the intake manifold next to the carb] is the connection of the vacuum lines to the vacuum advance and is switched on and off from the gears in the trans.
Ed
