No oil temp

carrooth · 10-18-2006, 09:50 PM

Well It's taken awhile but I finally got my 66 started. It's been dormant for about 7 years. I went through the brake system, repacked cv joints, fuel tank sealed, new fuel lines... Really it ran pretty good (once the smoke cleared) considering it's hibernation.

One problem I'm having is the oil temp gauge is not working. I've looked at previous posts and they get into different resistance at different temps. What I'd like to know is there something simple I can do to get the gauge to move so I'll know if it's the gauge or wire between sender and gauge, or if the sender itself is bad. I think on a different car long ago, I grounded the wire and the temp went full hot, but I'm not sure if this one works the same way.

Thanks

Jack Olsen · 10-18-2006, 09:58 PM

There are two slip-on connections at the tank where the wires meet the sender. They sometimes get pulled loose. I don't know which side it's on with the '66. With my 72, it was on the inside and required long needle-nose plyers.

carrooth · 10-19-2006, 11:23 AM

I don't think we're talking about the same thing. I need oil temp. I thought that was the sensor just below and right (about 4 o'clock position) of the cooling fan. Only one wire going there. Am I looking at the wrong sensor?

carrooth · 10-22-2006, 04:24 PM

anyone else? I'd really appreciate any help that could be offered.

Thanks again

DonMo · DonMo's Garage

Mine went weird when the connector came loose. Check your electrical connections from guage to sender. Something is loose.

carrooth · 11-06-2006, 03:41 AM

Troubleshooting, I grounded the green and black wire back at the sensor. There was no change on the gauge. I then disconnected the green and black wire from the gauge and grounded the spade connector on the back of the gauge. The needle now deflected full scale low (maybe went down 1/16" more). So the needle moved although I expected it to move the opposite direction. It seems to me there must be a bad connection between the sender and the gauge. I'm not sure where to start looking now.

Any idea where there could be a bad connection between the oil temp gauge sender and the gauge itself.

Thanks

Early_S_Man · 11-06-2006, 04:10 AM

Jay,

Here is the link for a high-quality schematic for your car:

http://members.rennlist.org/911pcars/L57.pdf

You can test the gauge itself with a 1000 Ohm potentiometer connected to gauge terminal and ground ... sweep the pot and gauge should sweep full range.

There are no intermediate connections between gauge and sensor, so that leaves only a few possibilities ...

1. Loose or corroded Faston connector or sensor tab. Clean and retension sides of female Faston xonnector.

2. Broken conductor under the insulation an inch or so away from Faston connector. Most likely scenario ... Green/Black wire near the sensor fractured due to vibration.

carrooth · 12-05-2006, 02:53 PM

I've done a little more troubleshooting on this no oil temp problem. I tested the sender with a multimeter prior to start and after running for a while and the sender seems to work ok. Using the numbers in another post by Early_s_man it's running about 215F after about 10-15 minutes idling in the driveway. I think thats about normal. It'd probably be cooler if I actually went somewhere, but not till I have new shocks and tires. Anyway, i then tested the connector that plugs into the back of the temp gauge and I have a good signal there also. It seems to me the problem has got to be the gauge.

Looking at the back of the gauge (tough to do with a bad back) there is a loose, not connected all green wire. Should this be plugged in somewhere?

Anything else that might keep the gauge from working?

Thanks,

Jay