The Temperature Gauge Conundrum
Thread Starter
|
Mountain Pass
Joined: Aug 2006
Posts: 143
Likes: 2
From: CT
The Temperature Gauge Conundrum
Hello all, I know its been quite some time since I've chimed in and I hope you are all well.
So I have a winter beater that I bought for 200 bucks last year ran great until the oil pump gave up the ghost.
Long story short. Old tired 300 out. Newer 1989 300 in with hooker headers, Offenhauser intake, and Quickfuel 450CFM carb in.
I transferred all of the old sending units from the old motor, and on this truck it has a two pin connector for the temp sender. I found that Odd as my 84 with the 351 is a one wire wonder.
Temp gauge doesn't work now, worked before. replaced sender with AC-Delco, OHMed out old sender had OL, new one OHMed good. Took a Key on Voltage from the harness connector I'm getting 5.2 Volts. Battery has been on a tender, and was disconnected entirely during engine swap.
I know on my 84 I can short the wire and get a sweep out of the gauge, whats the procedure for diagnosing a two wire gauge?
Thanks as always.
**Because I Know someone will notice, the picture was before I got it all back together, All grounds are connected. I've checked at least 10 times**
So I have a winter beater that I bought for 200 bucks last year ran great until the oil pump gave up the ghost.
Long story short. Old tired 300 out. Newer 1989 300 in with hooker headers, Offenhauser intake, and Quickfuel 450CFM carb in.
I transferred all of the old sending units from the old motor, and on this truck it has a two pin connector for the temp sender. I found that Odd as my 84 with the 351 is a one wire wonder.
Temp gauge doesn't work now, worked before. replaced sender with AC-Delco, OHMed out old sender had OL, new one OHMed good. Took a Key on Voltage from the harness connector I'm getting 5.2 Volts. Battery has been on a tender, and was disconnected entirely during engine swap.
I know on my 84 I can short the wire and get a sweep out of the gauge, whats the procedure for diagnosing a two wire gauge?
Thanks as always.
**Because I Know someone will notice, the picture was before I got it all back together, All grounds are connected. I've checked at least 10 times**
Senior User
Joined: Jan 2013
Posts: 171
Likes: 2
From: Tonopah, AZ
What year was the old engine?
My 83 is a one wire sender and I don't know why they would have ever needed two wires, unless to feed two gauges, or one gauge and an idiot light. The second "wire" (ground) is the thread contact with the engine block.
My 83 is a one wire sender and I don't know why they would have ever needed two wires, unless to feed two gauges, or one gauge and an idiot light. The second "wire" (ground) is the thread contact with the engine block.
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
The 2-wire sensor (typically near the thermostat) is used by the EEC-IV computer only, don't connect it to anything.
The 1-wire sender (elsewhere in the coolant flow, in the intake manifold or water pump on V8s) is used by the dash gauge or idiot light.
Your engine had both since it was computer-controlled.
The 1-wire sender (elsewhere in the coolant flow, in the intake manifold or water pump on V8s) is used by the dash gauge or idiot light.
Your engine had both since it was computer-controlled.
Moderator
Joined: Jan 2001
Posts: 56,984
Likes: 2,738
From: Virginia
I will repeat what the others have said, your two wire sensor is not for the temp gauge. It should be a one wire sensor, just like the oil pressure sensor. I can't remember which is which, but there will be a red/white wire and white/red wire. One will be for the oil pressure, the other will be for the engine temp sensor.
Thread
Thread Starter
Forum
Replies
Last Post
Slick-rides
1948 - 1956 F1, F100 & Larger F-Series Trucks
11
May 26, 2017 08:48 AM
78 & 87 Super Cab
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
7
Jul 6, 2013 11:09 PM
frankyford
1987 - 1996 F150 & Larger F-Series Trucks
3
Aug 2, 2009 03:17 PM
