Oil Temp Sender Location

[Lowell W]

My car has a Canton oil pan, with the fitting for the oil temp gauge in the front of the pan. During normal driving, I seldom see oil temps higher than 60°C, with water temps up to 80-90°C. Driving in the rain, the temp gauge drops almost to the pin.

I've checked my temp gauge with boiling water and it reads almost 100°C (close enough) with the entire sender immersed in the boiling water but if I pull it out so just the end of the bulb is in the water, it reads about 95°C.

I've come to the conclusion that, while the gauge/sender is capable of "near enough" accuracy, the location of the sender on the front of the pan and the location of the bulb in a pool of oil which is being cooled by air moving past the pan, are causing false low temperature readings.

The remote oil filter is ahead of the engine, connected to an adapter on the block with AN-10 lines out and back. The simplest solution seems to be to add a street Tee in the line from the adapter to the oil filter and locate the oil temp sender in the side leg of the Tee. With a Swagelok stainless 1/2" street Tee ($50+, BTW!), it will be a nice, simple installation, with the tube tucked in close to the block but I'm wondering whether I'm overlooking a better way to do this.

Has anyone had a similar problem? If so, is there a better way to solve this or somewhere else to plug in the oil temp sender?

Thanks,

Lowell

Edited for misspelling

[Velox]

Hi Lowell, I agree with you, anywhere on the oil cooler line system near the engine I think would be a more accurate temp source. On mine the oil temp sensor is at the remote oil filter mount in front of the engine, and the temps seem accurate. I used the other side of the mount to place a 20psi oil pressure switch which I wired to my dash red warning light, so if oil pressure falls and I'm not watching the gauge the warning light will get my attention for sure. I replaced my mechanical oil pressure gauge (tired of leaks) with a Smiths electric oil pressure gauge, it also seems to be very accurate. I had previously switched out the ammeter for a Smiths volt meter and installed a larger single wire alternator so my red warning light wasn't being used until I added the oil switch.

[timpound]

My spf has the sender located at the intake side of the filter housing.a wind blocking sheild was also installed infront of the cooler,i assume because temps during street driving were low.
tim
pictures are in my gallery,can't figuire out how to attach yet.

http://www.clubcobra.com/photopost/s...2&ppuser=26474

http://www.clubcobra.com/photopost/s...4&ppuser=26474

[Rick Parker]

timpound:
I have a S/W (72" tube) mechanical oil temprature guage with the bulb in the front of the Oil Pan about 1" from the bottom. The Oil Temp gauge rarely gets above indicated 160, the highest I have seen is 190. I too am concerned about the readings that I get. I have given some thought to wrapping the oil cooler hoses with insulation, even though it is blocked with a clear piece of plastic. Both of my temp gauges seem to read at least 20 degrees lower than I would expect. I have a 180 degree water thermostat and it runs an indicated 160-165 degrees at speed, but will go to indicated 190 before the fan switches on (which is about right) if I sit in traffic at a stop light, but cools right down once moving. I have thought perhaps the length of the 72" tubes for each gauge had something to do with it.

[Morris]

Reading the temp in the oil pan is actually a much better and quicker way to see what is going on inside of the engine......

Reading the oil temp on the way back to the motor has given the oil a chance to cool a bit.....

And if it's after the oil cooler it will be 15*- 25*degrees cooler going back into the motor.....

So we read it in the pan and going back into the motor.....

But only when we look at the gauges.....

Morris

[Lowell W]

Velox and Tim,

Thanks for your input. Tim, your photos raise another question: one line goes from the oil filter adapter on the block to the remote oil filter mount and the other line comes back from the mount to the adapter. The oil cooler is not connected, so the two ports on the mount on the side away from the motor are plugged. If the oil goes from the motor to the filter mount, through the filter and back as it is, what would make it circulate through the cooler if I connected the cooler lines to the other two ports? Is there a plug somewhere on the inside of the mount that you remove to make the oil go through the cooler?

Rick,

I don't think the length of the tubes is an issue. I considered insulating the fitting at the front of the pan but A) I don't see a way to do it without it looking like crap, and B) even so, it's still the coolest oil and I want to know the temp of the hottest oil.

Thanks,

Lowell

[Lowell W]

Morris,

If I Tee the temp sender into the oil line coming out of the adapter on the block which goes to the oil filter, I should get the highest oil temp in the system, no?

Lowell

[Morris]

Yes.....use a Petersen Tee..... if it's a electrical guage....ground the Tee....

[timpound]

lowell,
the engine block housing output goes through the filter, out the other side, elbowed & staight to the cooler,then goes back to input side of block housing.the temp sender is on the other input side of the filter housing,so it's getting a reading before the oil is cooled & before it goes through the filter.the plugs are as follows on the filter - one on second intake port (temp guage) & one on output.hope this helps,this is the way it was done by dennis althoff.
tim

[Lowell W]

OK, Thanks, guys!

Lowell