Oil temperature sensor in valve cover? Accurate reading?

[EsbenDenmark]

I have been researching were to install an additional oil temperature sensor. The best solution seems to be to install a sandwich adapter under the oil filter. like this:

SGAP5-2415 Toyota Oil Filter Sandwich Plate

Genuine SAAS oil filter sandwich plate and adaptor bolt suit M24x1.5 Toyota 1HZ 1HJ 1KZ diesel using Z334 or similar full flow oil filters and requiring 1/NPT ports for aftermarket pressure and temperature senders and gauge accessories

www.shopsaas.com

but those are expensive. Especially from Australia to Europe!!

I happen to have an old oil temperature sensor laying around from an old project. It is too big to install in a T fitting with the original oil pressure sensor location.

So I was thinking. There is also oil in the valve cover. It would be super easy to install the temperature sensor in the valve cover.... but would I get an accurate reading? I guess the sensor would in practice be reading the oil/air fumes next to the valves, but would there be a significant difference?

 

[Felde]

Temperature sensors (oil and water alike) work by surface. There is no accuracy if not fully submerged in the liquid to measure.
There is not sufficient oil pooling in the valve cover for that. Also the valve cover provides a huge area for heat transfer to air. I would expect significant lower temps in the valve cover in relation to the engine core.

Is it about replacing a factory gauge or adding an oil temp gauge at all (in addition to the water temp gauge)?

When it comes to accurate temperature measurements I learned: In many cases it is not the sensor, but the gauge that causes poor readings.
I replaced my factory gauge in the instrument panel by a quality gauge (VDO), with the respective matching sensor in same place of the factory sensor.
Huge improvement.
Important to know: Gauge and sensor type need to match. Any 'sensor laying around' will not necessarily give an accurate reading with the factory gauge or 'any' gauge either.
Cheers Ralf

 

[ATL Cruiser]

When it comes to accurate temperature measurements I learned: In many cases it is not the sensor, but the gauge that causes poor readings.
I replaced my factory gauge in the instrument panel by a quality gauge (VDO), with the respective matching sensor in same place of the factory sensor.
Huge improvement.

@Felde did you replace the actual gage inside the cluster or did you just add another gage to a gage pod?

I ask, because I'd like to replace the actual coolant temp gage in my cluster. It's pretty junk. But finding a matching gage insert is difficult....

 

[Felde]

I put a separate gauge on top of the dash, between the instrument cluster housing and the altimeter-clinometer housing.
At a point I was looking for a replacement for within the cluster, too, but didn't find anything (least of all anything more accurate).
If you are more lucky and find anything, please let me know.

My instrument cluster is original 1985 and actually working (just not overly accurate), so I wanted to keep it untouched. The factory gage is just disconnected. Ralf

 

[sodafeld1]

Yes, I did something similar and just left the original gauges alone. Coolant temp and oil pressure with separate senders and corresponding gauges.
I used a 'jackmaster' sandwich adapter for the oil pressure, the ancient fellow use to lathe them here from aeroplane aluminium, in Melbourne, but now gets them made in China. He sells on ebay, but shipping to Europe would be exy.

I really like the sandwich adapter idea. Really simple, doesn't take up much space and has three outlets. So I have an oil line for a bypass filter, one for the mechanical gauge and one for the electrical oil pressure sender.

I used autometer, it was good for awhile but their senders seem to have lost their quality in manufacture now. I used Marshall as a mechanical pressure gauge, it is solid.
If I went again I would go for vdo too, they make for merc.

 

[sodafeld1]

Pardon my ignorance, why oil temp? Are you doing some extreme rock crawling or racing?

 

[EsbenDenmark]

Ok so it makes sense that the sensor has to be submerged. So valve cover is out.

I am not replacing the original sensor. But are adding a water and oil temperature sensor.
I have both instruments and sensor from KUS so they should work.
No I am not going rock climbing.. but will be driving from Europe to Australia next year.
I guess if I go with the filter sandwich adapter I can add a pressure gauge also and will not have to touch the original sensor at all. Also there will be a outlet for a turbo oil line later.

 

[sodafeld1]

But I still don't ascertain what you get from oil temp? Why is that needed?

Coolant temp to monitor the head temp and therefore whether your head is about to crack from too much heat. And for warm up to a healthy operating temp. Can watch it climb in temp towing uphill for example, and cooling coasting down hill in gear, this temp range can vary 15c degrees. Or when thermostat opens or fan clutch kicks.

Oil pressure, not too high so your filter does not pop or too low and destroy your engine, whilst there normally is a shut off for low pressure. More so, reassurance that lots of the good stuff is pumped about.

But with oil temp what do you get to know from monitoring it?

I imagine the oil gets warm and would stay there pretty stable as a vat of hot oil would with regulated heat application controlled by the coolant temp. Oil temp would only go up and up if your coolant temp was going up and up. So it would already be too late for your engine if your oil temp goes up and up.

There certainly would be a specific oil temp you will never want to see go over.

As far as I understand, which is not much,, coolant temp and oil pressure is much more important.

Or, and I completely understand as I suffer from it myself, I simply like my bells and whistles, watching the cogs go round.? I understand that and it gives one a sense of greater affinity with ones engine.

Or, there is a perculiar fellow in Oz who picks up road kill, guts the animal, wraps it in foil and drives for an hour or so then eats his free roast meal!. I believe he goes by time and size of animal or portion. Smells it slowly cooking whilst driving. But then still, his coolant temp is controlling his oil temp..I don't think he worries about gauges too much.

Not trying to be a smarty pants, sincerely don't know. I have seen them for sale and wondered, what for? I bet racing cars have em.

 

[sodafeld1]

Ok, sorry for the hijack rant had to find out why.
from ferrari forum
'
Water Temp and Oil Temp is very different. If you are pushing a car hard, oil temp and pressure is very important. The first shouldn't be too high and the second shouldn't be too low.
Water is keeping the block cool, but the oil keeps the metal reciprocating mass lubricated so it can keep turning. The temp and pressure is necessary to know because, if the pressure drops then oil isn't going where its supposed. And the higher the oil temp the less it is capable of lubricating the bearings and crank. Overheated low pressure oil is the ideal recipe for seized bearings.
Oil temp is not completely dependent on the water temp. It gets cooled separately in high output engines. And high rev motors need to have the oil temp and oil pressure monitoring system. Because they almost always have separate cooling system, and heat up very disproportionately to the water temp.'

But tractor like diesels are not high revving..anyway learnt something. Still not convinced I need one even if I tow 2t uphill in 40c regularly, good oil pressure and not over 90c is fine by me. My engine is not high output.

 

[JuanJ]

Hello,

JDM fire engines do have an oil temperature gauge. The oil in an engine and a gearbox running a water pump while remaining stationary for prolonged periods can get very hot and lose its viscosity. Reduced viscosity means undesirable changes in pressure.

Engine oil goes through a cooling circuit before returning to the sump, if I remember correctly. A temperature gauge is a good way to know whether the oil cooler is working properly.

If I were to drive from Europe to Australia, I would have the oil cooler checked and repaired. Help may not be available during the journey.





Juan

 

[bj70bc]

Stupid question....how does one drive to australia

 

[bj70bc]

.....inquiring minds and all
I feel like im missing something

 

[EsbenDenmark]

No the 1hz is most definitely not a high reving performative engine. We will however be at 3.5 ton and going through very hot area and over mountain passes.
This I why I want to be able to keep an eye on the engine and be able to slow down (like the 1hz can be any slower ) or stop if needed.

Me 1hz does unfortunately not have a oil cooler so I want to be careful.

Stupid question....how does one drive to australia

Get behind the wheel then drive but yes there will a few ferries and I will need to from the last little stretch from fx Indonesia.

 

[sodafeld1]

Ohh, really pardon my ignorance please, didn't know hz has no oil cooler...wow!
So does the hz engine oil temp totally rely on the coolant traveling throughout channels in the head and block?


Gosh you learn a lot here.

My mate just recently got a hz troopy, so soon I can have a closer look at this legend.

 

[EsbenDenmark]

Ohh, really pardon my ignorance please, didn't know hz has no oil cooler...wow!
So does the hz engine oil temp totally rely on the coolant traveling throughout channels in the head and block?


Gosh you learn a lot here.

My mate just recently got a hz troopy, so soon I can have a closer look at this legend.

Well. There is a small "oil cooler" under the oil filter. More of a small heat exchanger. But no actual oil cooler externally.

 

[sodafeld1]

Well. There is a small "oil cooler" under the oil filter. More of a small heat exchanger. But no actual oil cooler externally.

View attachment 3250400

View attachment 3250401

Ok, about half the size or less of the 2h one, got ya.

So what do you do if your oil temp is too high? Just switch off and wait?

 

[JuanJ]

Well. There is a small "oil cooler" under the oil filter. More of a small heat exchanger. But no actual oil cooler externally.

Hello,

That oil cooler/heat exchanger does the job for a 1HZ engine. Keep in mind that the 1HZ is intended to work under harsh conditions.

I suppose you will stop and allow the oil to cool down if the temperature becomes too high in, say, a mountain pass. Keep in mind that engine coolant and exhaust gas temperatures will rise well before the oil temperature will.






Juan