# Sudden increase in oil temperature after water pump n engine oil change



## marcus.tan.5074 (Sep 16, 2015)

Hi all.
I am new here.
Own a 2010 Mk6 GTi.
Was on Motul 8100 Excess till i changed to Castrol Edge titanium 5W40 and replaced water pump.

On 8100 excess, my average oil temperature was hovering ard 98-99 to max 100-101deg.

After changing to Castrol n after the water pump, my oil temperature went as high as 108deg and also averaging around 103-105deg.

The main thing i do not understand is where is there a big increase In temperature.
Other friends using the same oil are having temperatures of 90+ but not more than 100deg.
The only mod i did recently was installation of an AWE tuning downpipe.( which threw a CEL)

Can some kind soul please enlighten?

Thank you v much


Sent from my iPhone using Tapatalk


----------



## stratclub (Feb 3, 2007)

3 or 4 degrees difference is not enough to worry about. Pretty much everything else in your life should be of way more concern.:facepalm:


----------



## marcus.tan.5074 (Sep 16, 2015)

Up to 10


Sent from my iPhone using Tapatalk


----------



## marcus.tan.5074 (Sep 16, 2015)

10deg is alot.i m v concerned if there is anything wrong.
Could the downpipe have caused the temp to increase?
I m still on stock map


Sent from my iPhone using Tapatalk


----------



## Eric D (Feb 16, 1999)

OP's location would help up verify if the climate has changed.
Heat wave?


----------



## rommeldawg (May 25, 2009)

look at the downpipes proximity to the oil return line especially as compared to the stock one. i can not see the wp involved in the issue and the oil itself seems unlikely


----------



## SandCastle (Sep 10, 2013)

It might be due to a difference in oil viscosity. With usage the Motul oil has sheared down to 30 weight which makes the engine run more freely and cooler as compared to fresh Castrol which has not accumulated enough hours to lose viscosity. It's been well documented that a viscosity decrease lowers oil temperature.


----------



## marcus.tan.5074 (Sep 16, 2015)

I used motul n the temperature was beautiful as i could recall.
But my other friends using castrol did not encounter such high temps.i probably live with this till next oil change


Sent from my iPhone using Tapatalk


----------



## marcus.tan.5074 (Sep 16, 2015)

I hit 112deg today....was only doing 100-120km/h.
Mainly cruising....
Whats the symptom of a faulty water pump?


Sent from my iPhone using Tapatalk


----------



## agent007 (Jan 15, 2003)

watch the aftermarket pumps. Some even claim OEM replacement.

The propeller will simply be a piece of flat metal with bent ends this IS NOT GOOD.

The factory OEM pumps used a plastic REAL propeller style prop with angled and curved gradual propeller blades with a concave housing surrounding it.

The good pumps will have a prop that looks like a REAL boat style propeller not simply a flat piece of metal with bend flat blades.

I just replaced the flat style prop on an older 16v with the factory style and the motor went from running way to hot at like 210-220 back down to normal around 190 or so.

You should also notice the car cabin heater itself will not run as hot or more importantly STAY hot as it used to if your pump propeller sucks. 

It just simply won't turn enough water.


----------

