Me again!!
I have an oil sensor sandwich plate and then a MOCAL oil rad take off plate on my car.
The oil temp sensor reads spot on I recon and is probably on the engine outlet of the flow. This means that on track the oil rad is doing its job, I
can feel the return is substantially cooler than the oil rad feed, but my sensor is still reading high temps (110deg). I work my car hard on track so
I would expect it to climb.
Water stays cool at 80ish.
I was thinking of relocating my sensor to the rad return but then it will read cold until 80deg when the thermostat opens.
Surely everyone else must have the same issue. Where are your oil temp sender's located? If they are on the sump they would also read cooler as
they are no straight out the engine, it run down and sloshed around in contact with a cool sump pan.
Am I interested in the immediate engine oil temp at outlet or oil engine supply once cooled?
You want a reading from half way up the oil level in sump,that's the best average.
If you look at dry sump systems they read the temp from half way up the oil tank.
I asked the same question here a few months back.
For ease I bought a Bosch 0 281 002 412 as it has the same thread as the zetec sump plug (M14 x 1.5 I believe).
I've then hooked it up to a DL1 datalogger.
All the info regarding resistance values is on the JPSC site forum. It turned out to be similar to one of the motorsport part numbers NTC M12-H
(aka 0 281 002 170).
So my one is in the sump for an overall average.
I suppose measuing at the hottest point would maybe be more valuable as you can see if the oil is getting really hot as some point on its way round.
[Edited on 19/5/21 by pigeondave]
[Edited on 19/5/21 by pigeondave]
You don't need to know the hottest point though, if you did this on a turbo charged car you would be permanently worrying about nothing!
The oil temp average is what you need to know,this is what's in the sump/tank being sucked up into the engine to the crank etc.
quote:
Originally posted by CosKev3
You don't need to know the hottest point though, if you did this on a turbo charged car you would be permanently worrying about nothing!
The oil temp average is what you need to know, this is what's in the sump/tank being sucked up into the engine to the crank etc.
quote:
Originally posted by pigeondave
quote:
Originally posted by CosKev3
You don't need to know the hottest point though, if you did this on a turbo charged car you would be permanently worrying about nothing!
The oil temp average is what you need to know, this is what's in the sump/tank being sucked up into the engine to the crank etc.
I see what you mean.
When does or maybe how long (time), does an oil need to be held at a higher temperature for before its considered to have broken down.
In my mind is it like cooking a fried egg? You only have to get it hot once for it to change to a different state which you cant go back from.
If the OP is concerned with the hottest temp maybe they're thinking similar to the above analogy.
Maybe a better way of wording the question is.
How long can you hold an oil at XXX degrees before it breaks down? or what is the max temp / time before oil breaks down.
I suppose this (the above) is what is most important, as we're taking an average temp over all of the oil.
Sorry for rambling on.
[Edited on 19/5/21 by pigeondave]
[Edited on 19/5/21 by pigeondave]
So then the question is all about the max oil temp at its hottest.
I don't want to put a sump sensor in I don't want anything dangling down. I don't really want to move the one I have, but the oil rad
return is right next to the current sensor so very convenient.
I'm going to shield off the area to prevent excess heat soak From the exhaust which is close by. I'm going to see if I can find a oil flow
diagram for the 4age and see what order everything is in.
Standard oil flow will be sump - pump - filter - oil galleries/bearings - drain back to sump. Your sandwich plate and cooler will be either before or
after the filter.
As the oil gains temp as it's pumped around the engine it'll be hottest as it drains back and cools in the sump (not a lot at full chat),
probably gains a (tiny?) bit back in the pump. I'd say the sump and the sandwich plate will give you the highest readings and after the cooler
(unsurprisingly) the lowest. There's not really anywhere else practical to take it that will give significantly different results.
Mines in the sump but I have thought of fitting a second one after the cooler that I could switch over to just out of curiousity.
I have seen dry sump systems with the cooler on the low pressure return to the tank, so sensors in the tank give low readings. Personally I'd
prefer it reading the temp going into the cooler in this case.