Matthew,

If your TC is long enough, put it in the dipstick tube. Make sure
it is the same insertion length as the dipstick and you'll be clear
of internal rotating parts. If you do put it on the oil filter,
you'll need to insulate the filter/TC with something like
fiberglass or rubatex (rubber pipe insulation). Without effective
insulation, the small mass of the TC tip, and the difficulty of
getting a good thermal connection against the filter, will result
in the RMS temperature value observed by the TC being significantly
cooler than the oil filter surface (which will also be
significantly lower than internal oil temp) due to convective
losses.

If you want to get *real* fancy, you can get a malleable stainless
steel probe to replace the dipstick permanently. Just mark the
sheath with the oil level markings, put a mini plug on the TC
leads, and presto! Probe cost should be around $50-60. I'm getting
some Type T's tomorrow, so I think I'll check on the price for one
of these puppies as well.

Keith Hughes

Matthew Pollard wrote:
>
> i want to measure my oil temp but don't have a fancy VDO temp sender, etc.
> But i do have fancy temperature probes that are just a small wire i can
> put anywhere (type K thermocouples). I would be happy to snake one into a
> coolant line (like SeanB did once upon a time) but am a reluctant to do
> that to an oil line as the consequences are much more sever if it
> leaks....
>
> so what about strapping my thermometer to the body of the oil filter? I
> know the oil cooler is there, but my logic is that after a while, the
> whole system is in equilibrium and the coolant won't cool the oil THAT
> much, right? i mean after a while, like an hour or so of driving.
>
> The motive of this research is two fold. I recently installed a cooler
> thermostat and radiator fan-switch and would like some date to support out
> hypothesis that is the the correct system for these rig's.  And the second
> point of note is this from driving this past weekend. The ambient
> temperature was between high 20's to high 30's. When cruising along at
> highway speeds, after about an hour the front heater would start to loose
> it's burning hot air but instead more a mild heat would come out.  I had
> the rear core open and the rear fan on the 1st setting.  I had the air
> flow on FULL in the front. To get more heat i would throttle the front air
> to 1/2 or 2/3 off.  My concern is it may be running too cold. The
> ever-so-accurate needle on the dash sits steady at 1/2 high at all times
> once the engine is warm.
>
> the books i have on engines always say the ideal oil temp is 109deg C.
>
> Thanks
> matthew
> 86 syncro westy tiico