oil temp

[Whodeeny]

Originally Posted by davids2toys

FWIW, just a few thoughts on weird oil temps:

1) The builder of my car actually had the water temp gauge sender screwed into the oil pan and the oil sender screwed into the hole for the water sensor. He actually drove it like this for ten years! Those gauges and senders are identical except one is labeled water and one is labeled oil. I thought I had a faulty water gauge because it was actually reading oil temp at the pan which is nothing close to the water temp at the top of the engine. It would also behave funny. The water temp would read about 180, but when you started driving above 3000 RPM for any reason, the water temp gauge temp would start rising very quickly and the only way to make the temp come down would be to drive easier to keep the RPM under 3000. When I asked the previous owner he said it had always done that and he had just gotten used to it.

2) I bought a new pan from Canton about 5 years ago, still not installed...LOL I had them weld in a new bung much lower so I could be sure the bulb was submerged in oil at all times. I did not like the stock canton higher location for the obvious reasons. To me it was barely in the oil at full, so if you were not at full oil level or driving aggressively you had a very good chance of reading the air temp in the oil pan. They liked my idea and told me they would consider a design change. I don't know if they ever did this going forward

So does the oil temperature in the pan differ depending on where the oil temperature is measured? I have an Aviad oil pan and the sensor is placed very low in the pan at about the same elevation as the drain plug. The oil temperature just barely gets to a point that I would call acceptable. I have an oil cooler installed and I blocked off air flow to the heat exchanger trying to bring the oil temperature up. It didn't come up very much. Plus the pan hangs down a little bit so that the lower 20% or so of the pan is probably in the air stream passing under the car. My hope is that the oil that is being pumped to the bearings is actually hotter than that which is at the sensor and what I am seeing on the gauge. Is this just wishful thinking?
BD

[davids2toys]

I would say your thinking is pretty accurate. Also I think taking the reading at the pan is cooler than it would be at the head, but I could be wrong on this. I blocked mine off with see thru plexiglass because I like the way the oil cooler looks

[Gaz64]

Originally Posted by Whodeeny

So does the oil temperature in the pan differ depending on where the oil temperature is measured? I have an Aviad oil pan and the sensor is placed very low in the pan at about the same elevation as the drain plug. The oil temperature just barely gets to a point that I would call acceptable. I have an oil cooler installed and I blocked off air flow to the heat exchanger trying to bring the oil temperature up. It didn't come up very much. Plus the pan hangs down a little bit so that the lower 20% or so of the pan is probably in the air stream passing under the car. My hope is that the oil that is being pumped to the bearings is actually hotter than that which is at the sensor and what I am seeing on the gauge. Is this just wishful thinking?
BD

That's how all oil pans work.
Airflow around the pan is part of the oil cooling design.

You should move your oil temp sender to the oil filter housing. That will be a better average of oil temp within the engine.

Another way would be to have the sender in a constant fall of oil from the crankshaft, or within an oil drainback within one cylinder head.

[patrickt]

This has done me good for 15 years. That cap tube is running to an old Smiths mechanical oil temp gauge.

[Gaz64]

Patricks car above is a good example.

The sender gets doused with hot oil leaving the crank,cam,heads draining etc BEFORE the oil gets a chance to be cooled off in the pan.

Reading near the bottom of the pan is as cool as the oil could get prior to the oil being picked up again by the oil pump.

Just like a coolant temp sender is fitted at the hottest part of the engine prior to the coolant going to the radiator, the oil temp sender is best located as like Patricks or my case as above.

[patrickt]

It would absolutely never occur to me, when diagnosing funky oil and water temperature changes, to look and see if the gauges were switched. I would have to pull one of the senders out and pop it in a pot of boiling water. Then, when I looked at the dash, I would start laughing. That's one of those goofy stories you put in a car magazine, which I haven't actually seen in years now.

[davids2toys]

Originally Posted by patrickt

It would absolutely never occur to me, when diagnosing funky oil and water temperature changes, to look and see if the gauges were switched. I would have to pull one of the senders out and pop it in a pot of boiling water. Then, when I looked at the dash, I would start laughing. That's one of those goofy stories you put in a car magazine, which I haven't actually seen in years now.

It never occurred to me either basically because the gauge was working normally except for taking a little longer to come up to temperature than I thought was normal, and only got real hot when I went above 3000RPM so I was thinking I had an engine problem. As soon as I bought the speed down to 3000 RPM or lower, the temp would come back down to 180 deg

[cycleguy55]

Originally Posted by Gaz64

Patricks car above is a good example.

The sender gets doused with hot oil leaving the crank,cam,heads draining etc BEFORE the oil gets a chance to be cooled off in the pan.

Reading near the bottom of the pan is as cool as the oil could get prior to the oil being picked up again by the oil pump.

Just like a coolant temp sender is fitted at the hottest part of the engine prior to the coolant going to the radiator, the oil temp sender is best located as like Patricks or my case as above.

As noted here ( https://www.460ford.com/threads/gpm-...38/post-833782 ) the standard volume Ford 460 oil pump is rated at 19 GPM - that's 76 quarts PER MINUTE - presumably at highest RPM. At that rate an 8 quart pan will have it's oil replaced 9+ times per minute, but obviously fewer times at lower RPM. I suspect FE and Windsor engines aren't that much different.

Whether bypassed to the pan or pumped into the engine, the rate of flow in the oil pan will ensure any cooling in the pan is minimal. We don't need to worry about whether the oil temperature is off by fractions of a degree, which is the likely effect of such cooling at those flow rates.

My temperature sender is in the lower front wall of the pan - I'm not in the least bit concerned about how accurate it is.

[patrickt]

Originally Posted by cycleguy55

Whether bypassed to the pan or pumped into the engine, the rate of flow in the oil pan will ensure any cooling in the pan is minimal. We don't need to worry about whether the oil temperature is off by fractions of a degree, which is the likely effect of such cooling at those flow rates.

My temperature sender is in the lower front wall of the pan - I'm not in the least bit concerned about how accurate it is.

I would say any oil temperature gauge is better than one that is plumbed in to the coolant system.