FRporscheman

How would the reading from an oil temperature sender installed into the drain plug be affected by the presence of an oil pan baffle (with a trap door) which, in normal situations, would be at least partially blocking the flow of oil around the drain plug?

My NA has the sender in the drain plug, I like the set up. I am building a 951 engine and it has an oil pan baffle. I don't really want to put the sender into the turbo drain banjo bolt because I want to see average sump temps, not max. But it might not be good to use the drain plug in my case.

mattipuh

we just made a hole with threads to oil pan.
backside of the pan, closer to oil drain plug to get possible chips out.
Has been working well so far..

thomasmryan

linsey sells an adapter for the oil return hole..be nice to be monitor inlet and outlet temps on the cooler

FRporscheman

I guess I'll just put one in both the drain plug and turbo drain banjo bolt, compare them for a while, and find out for myself if the reading at the drain plug is affected by the baffle.

thomasmryan

the baffle is going to transfer the heat by conduction. steady state, everything should read the same.

944hal

Do you have an oil level sensor? I took mine out and put the temp sensor there.

FRporscheman

I do have a level sensor, and I want to keep it.

Steady state, sure, it will probably read right, but I'm worried about on the track, during a left turn. Especially on tracks with mostly left turns (like my home track), the reading may start to lag behind as the engine warms up.

Van

How did you get it low enough to the oil level? Or is it just measuring the pan temp (which is certainly valid).


Not an issue on cornering - the oil temp doesn't fluctuate that much. In fact, to reduce the sizes of your data files, you should have oil and water temp sample at 1 Hz max. (Because they just can't change more quickly than that.)

Oil pressure and RPM should be sampled at 10 Hz or so (maybe up to 50 Hz if you have a lot of storage, but again, they just can't fluctuate that much over the course of a second).

Now, when you get to sampling shock movement, that's a different story. You want that at 200 Hz. At 100 MPH, you cover 150 feet per second. There could easily be dozens, if not hundred, of road surface variations cause shock movement in that one-second slice of time. (Put another way, in 1 foot of distance at that speed, the crank shaft might do a half rotation.)

944hal

[QUOTE]How did you get it low enough to the oil level? Or is it just measuring the pan temp (which is certainly valid).[/QUOTE]
Van,
Putting the oil temp sensor where the oil level sensor was should be low enough to be in the oil itself. Unless, I assume, the oil level drops below the sensor. And yes, it will measure the pan temp.

Van

The oil level sensor has a little right angle on the end (if you've ever tried to pull one out, you know what I mean). I'm pretty sure the full oil mark is below the level of that hole.

Dave W.

Yes the oil level sensor hole seems to be a little high.

FRporscheman

But the 90 degree angle is turned upward; the float is (a little bit) higher than the hole. I would think the static full oil level would be higher than the hole but I could be wrong.

I have a spare oil pan in the garage, I guess I can try to pour 6 quarts of water into the sump to see if it reaches that hole.

Van

I don't actually remember which way it was turned... but thought it was down.

Please test and let us know what you find!

FRporscheman

Is it weird that the hard part of that test is not finding a spare oil pan (I have 3) but finding a way to measure a quart of water? I'll have to use a 16.9oz water bottle and do the math.

FRporscheman

Alright, in the name of science, I dug out the oil pan with the level sensor hole (it was the mostly deeply buried of the 3... of course...). Note that the black plastic insert is removed. It took 5 16.9oz water bottles to make the meniscus bulge over the edge of the hole, a little bit more and it dribbled out. So that's 84.5 oz which equals 2.64 quarts.

The level at that volume is nearing the level of the back of the pan (which is lower than the front of the pan). The level sensor hole is completely below the level of the front of the pan. I'm pretty sure that with the black plastic insert, and 6.5 quarts of oil, the level is up in the rear of the pan at least partially, and the entire level sensor hole is submerged.

BTW, the level sensor float's bottom represents oil being low by about 2 quarts (when the warning light goes on, it takes about 1qt to bring the level to MIN on the dipstick).

I'm still keeping my level sensor, though.