kevincnc

With the sender in the drain plug, my oil temp rarely goes below 210 after warming up, even on cool nights (around 70 deg F.) When I'm in slow traffic it gets up to 220 or 230. Reading past posts on oil temp, it seems that these temps would be more normal for the track than just driving around town not even using any boost.

I would think that since it has the extra oil cooler that would help. Is there something wrong or are those temps normal for city driving?

Oddjob

Thats about right, regardless of outside temp or usage - because of the oil thermostat.

There are two ratings on oil thermostats. I recall the original ones are little higher, later (superceeded part number) are a few degrees lower; both are somewhere in the 95-105 deg C range (200-220 deg F)

SamGrant951

From memory mine if sitting in traffic for awhile on a hot day will creep into the 200s (200-210) but dont think its passed 210 but once or twice. At highway cruise its usually around ~180. Mine is also in the drain plug and I plan on installing a KISS cooler this winter...

AL951

That is alittle high. Maybe because if the thermostat.

mine is always around 200 - 210. on stop and go traffic it may go over 210 but after driving on the open road it goes back down.

Regards,
AL

Mike Buck

Where did you get the drain plug sender? Is that a good place for reading?

I want to see my oil temps now that I am racing more and pushing the car much harder. Running only the stock cooler and Redline 20w50.

RolexNJ

Mike, just running stock cooler? Measure your temps, but you need a bigger cooler or an additional one. You track way to much to not have one. Must have for you dude.

RKD in OKC

The oil thermostat is stamped with an 85C that's 185°F.
I think my oil thermostat has gone bad because my oil is getting hot enough that my oil pressure starts dropping. When I put an infrared temp meter on the lines feeding my oil cooler after the car is well warmed it is only at 150°F and the oil pan is at 195°F.

kevincnc

Hmm, thanks for the feedback guys. I actually have the stock cooler, was thinking of the extra tranny cooler that's on the '88 S and '89's. I read some past "oil thermostat" threads and someone said there were 105 deg C (221F) thermostats on earlier ones, but the ones available now are 95C (203F). Someone also said that the oil needs to be at least 212 to "boil off" contaminants. Seems to me that over 212 would only "boil off" water, which would just re-condense when the engine cooled.

I think I'll just put in a new one and see what happens.

Mike- I tapped my own drain plug for the sensor.

Any more opinions would be very welcome.

M758

230 in slow traffic seems like it would be normal.

In slow traffic you get alot less air flow to the oil cooler and over the pan. Road is warm and sends heat to the pan. Also lower RPM mean less oil flowing thus more oil temp.

However I really don't know what oil temps should be on the street. My drain plug gauge got to 230-240 in my last race. I think I saw as much as 260F during a 100F+ track day.

Of course that is on an NA with a Turbo oil cooler. How warm did the oil get at the last DE?

kevincnc

Joe- I think the highest I saw it was around 240, so 210 just seems a little high for putting around.

hosrom_951

210F in stop and go traffic, maybe slightly higher, this is in 120+F summer heat

180-190F duing crusing, and 200F more/less with spirited driving.

Oddjob

As I mentioned earlier, the original oil therms are rated at 105 C (221 F) - I dont know when the part was superceeded to the lower temp therm, but 105 was used up through MY 89 (my mid year production 89T had a 105 therm in it, as well as my two 87 944's, and a spare 88TS engine).

I cant exactly remember the rating on the newer therms, but its 95 or 98 C. When I swapped out the therm in the 89T, I did take some pan temps with a thermocouple down through the oil filler cap, and it was 205-6 F (which is mid 90's C, and I remember it being damn close to the rating on the newer therm).

Assuming you have the stock therm, if your oil temps are below 220F, the oil is not flowing to the cooler. Since guys are running actual oil (in the pan?) temps below this, the coolant system apparently takes much of the heat transfer load of cooling the the oil. You may want to check the condition of the coolant system (how high is the coolant gage temp when the oil temp is reading high?).

But I still would not worry about any temps below 220, and I dont think +10 is anything to be too concerned about either.

250-260 range is where I would start thinking about adding an additional cooler for hard/track use.

Also, you may want to confirm the accuracy of the gage/sender with either another gage, or with a source of known temp (e.g. boiling water).