Oil temperature

[Stevec]

I've just fitted an oil temperature gauge and going on a one hour drive it showed the engine getting up to just over 130c , especially on the hills but mostly ran at about 110-120c.
I could hold the oil dipstick ok, it was hot but not burning.
Question is my bus running too hot? And if so do I need to an external oil cooler? Or am I just worrying about nothing as I can hold the dipstick?

The pistons were upgraded last year to 88mm and bigger heads so she's a 1750cc

Thanks

 

[Zebedee]

130c seems very hot.
Where is the sender and what speed were you driving?

On my stock 1600 bay with VDO dipstick sender it sits at about the 100-110c mark at 60-65mph, though i think it possibly under reads by 5-10c.
Have you tested the sender in boiling water to see how accurate it?

 

[Stevec]

The sender is a sump one fitted on the drain plug. I was travelling probably about 50-55 the whole way but like I said it was on the hills that it went up.

I haven't tested it, I'll do that this weekend

Thanks

 

[subheatadey]

Just wondering if you have heater control flaps fitted - And if so are they operating tickety boo? And is your tinware sorted i.e hoover bit on cooler? Just thought is your cooler in good nick?

 

[Alex VW Heritage]

You should not really go over 100 degrees, at 110 degrees the oil will start to break down.

if got to 120 i would personally do an oil change as soon as humanly possible!

I would fit an external oil cooler in addition to the stock one on anything bigger than a 1641cc, I know Tricky and others disagree.

 

[StuF]

Have you tested your sender in a pan of boiling water to measure how accurate it is?
Some have been known to read 10/20 degrees out!

If your oil got upto 130 it would be cooked!

 

[Stevec]

Thanks guys. Tinware is good as I helped put the engine back in but I will double check.
First thing I'll do is check the sender and go from there, if it's accurate I'll go for fitting an external oil cooler so I'll be in touch Alex.

Thanks again

Steve

 

[Zebedee]

Is the ignition timing spot on? If its too advanced temperatures rise dramatically on hills. Mine shot up 30c before i realised it was getting 35degrees total advance.

Theres a reason why they call them worry guages though. :lol:
If you can still hold the dipstick its probably not too hot though.

 

[rlepecha]

Depending on if you're using synthetic or mineral oil the temperature it breaks down at is different. Remember the oil sees much higher localised temperatures than 100 degree, like the actual cylinder wall!

 

[Stevec]

Weird I've put the sender in a bowl of boiling water and the gauge is hardly moving?? It's a 50-150c gauge so it should show something??

 

[subheatadey]

Is it capillary or wired in which case is it wired correctly?

 

[Stevec]

Wired. Yep straight from the sender to the gauge S post.

 

[Zebedee]

If you're testing it in boiling water remember the sender needs an earth too (its usually earthed through screwing it into the case).

 

[Stevec]

I was thinking that...derrrrr :roll: I'll tape some wire to it and try again, cheers

 

[subheatadey]

You could check the sender resister if you have a multimeter? Here is a you tube vid https://www.youtube.com/watch?v=wFHWpgHMAvY" onclick="window.open(this.href);return false;

 

[Stevec]

Right checked it on the gauge and the gauge only went as far as 70c ( it's a bout minute time I've taken the saucepan outside so would it of cooled 30c?) then did the yet with a meter and it went from over a 100 to 0.04 on 20k ohm setting.

What do you guys think? External cooler?

 

[StuF]

Doubt it would have cooled 30 degrees in 1 minute!
Shame you dont have a kettle you could take to the garage or outside and sit in it that - its what I did

Sounds like the sender is under reading significantly

 

[Stevec]

But even more worrying that my gauge reached 130!!! Probably got a dodgy sender and gauge :?

 

[Paul Weeding]

Generally you'd use a normal thermometer to do a comparison

 

[rlepecha]

Get yourself a digital food temp gauge with a long probe, you can put that down the dipstick after a long run.

I've got a very accurate industrial thermocouple fitted into the appropriate sized sealed tube sat in my dipstick hole. My old engine consistently ran at at or above 120c when cruising at 55mph. My new engine sits around 110c at 60mph, but the barrels and rings are still bedding in.

Seems to me that the dipstick sensor either reads 15 degrees more than where everyone else's sensors read(possible as its just below the 2nd barrel) or most people's gauges still aren't that accurate. Mine is correct to within +/-1 degree and gives a digital readout.