Printable Version | Subscribe | Add to Favourites
New Topic New Poll New Reply
Author: Subject: Oil temp sensor location and high reading
bi22le

posted on 17/5/21 at 09:09 PM Reply With Quote
Oil temp sensor location and high reading

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?





Track days ARE the best thing since sliced bread, until I get a supercharger that is!

Please read my ring story:
http://www.locostbuilders.co.uk/forum/13/viewthread.php?tid=139152&page=1

Me doing a sub 56sec lap around Brands Indy. I need a geo set up! http://www.youtube.com/watch?v=EHksfvIGB3I

View User's Profile View All Posts By User U2U Member
CosKev3

posted on 18/5/21 at 08:30 PM Reply With Quote
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.

View User's Profile View All Posts By User U2U Member
pigeondave

posted on 19/5/21 at 07:59 AM Reply With Quote
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]

View User's Profile View All Posts By User U2U Member
CosKev3

posted on 19/5/21 at 08:09 AM Reply With Quote
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.

View User's Profile View All Posts By User U2U Member
pigeondave

posted on 19/5/21 at 08:25 AM Reply With Quote
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]

View User's Profile View All Posts By User U2U Member
CosKev3

posted on 19/5/21 at 11:13 AM Reply With Quote
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]


The oil is never sat still anywhere though to break down like that, it's at high pressure and flowing fast.
The only chance of this happening is in a turbo charger if you switch the engine off with the turbo glowing red hot.

[Edited on 19/5/21 by CosKev3]

View User's Profile View All Posts By User U2U Member
bi22le

posted on 19/5/21 at 08:04 PM Reply With Quote
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.





Track days ARE the best thing since sliced bread, until I get a supercharger that is!

Please read my ring story:
http://www.locostbuilders.co.uk/forum/13/viewthread.php?tid=139152&page=1

Me doing a sub 56sec lap around Brands Indy. I need a geo set up! http://www.youtube.com/watch?v=EHksfvIGB3I

View User's Profile View All Posts By User U2U Member
adithorp

posted on 19/5/21 at 08:37 PM Reply With Quote
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.





"A witty saying proves nothing" Voltaire

http://jpsc.org.uk/forum/

View User's Profile View All Posts By User U2U Member

New Topic New Poll New Reply


go to top






Website design and SEO by Studio Montage

All content 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [ 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.