High Oil temperature, Concerned the temperature is getting to high too fast . Options

[Ron914]

In preparation and hope that I pass my smog test I want to go on the So. Cal.Toy Drive in my 914 on Saturday (not sure if this is a good idea) .

I need to address what I think might be a high oil temp problem .

After driving around town for 30 minutes the photo shows my oil temperature oil gauge and a actual thermometer reading using a turkey fryer thermometer.

The needle on my console gauge gets very close to the red high mark and sometimes just about to cross into the red .

At this point the turkey thermometer reads ~216 F degrees .

My Dakota Digital head cylinder temperature reads 111C (231F) .

It is almost 80F here today in sunny So Cal. but this seems too high for me . What would be a normal reading for the oil temp gauge?

This is a newly rebuilt motor (less than 300 miles on it).
I did not replace the oil cooler (its original) but it was flushed and was clear.

The baffles are held open by spring tension since the thermostat is not working but I checked they were open by removing the coil and checking through the bolt hole. This should be ok until I get a chance to replace it .

If I pass my smog check tomorrow or Thursday I am hesitant to take the car on a long canyon drive , so not sure if I can attend the toy drive this Saturday.

Any thoughts ?

[brant]

It’s not broke in yet
It will come down if only a little bit
(Maybe 10 degrees)

These cars run hot
I’d run synthetic after it is full broken in as it doesn’t break down as quick at temperatures

So many people add an aux cooler for a reason

I have had many teeners and put coolers onto all of them except 1
Sold that car instead

[worn]

It’s not broke in yet
It will come down if only a little bit
(Maybe 10 degrees)

These cars run hot
I’d run synthetic after it is full broken in as it doesn’t break down as quick at temperatures

So many people add an aux cooler for a reason

I have had many teeners and put coolers onto all of them except 1
Sold that car instead

When you have added remote cooling, where was your favorite spot for the exchanger?

[Superhawk996]

Do you have the stock 200c temp sensor?

[Ron914]

Do you have the stock 200c temp sensor?

Yes I do .

[Superhawk996]

Do you have the stock 200c temp sensor?

Yes I do .

The edge of the red zone is supposed to be about 300F.

You say you’re running 216F so there is a disconnect somewhere if you’re getting to the red zone in 30 minutes of street driving.

Get your smog test but you should get this figured out before extended driving.


See top right graphic for approx temperatures with 200c sender.


Does gauge work properly (ie all the way to the left when cold)?

Have you verified wiring? The wire from the sender should not have any DC voltage on it. Should be high resistance when cold and rapidly decreasing resistance as oil warms up.

What size oil pump are you running? Do you know your oil pressure?

[Ron914]

It’s not broke in yet
It will come down if only a little bit
(Maybe 10 degrees)

These cars run hot
I’d run synthetic after it is full broken in as it doesn’t break down as quick at temperatures

So many people add an aux cooler for a reason

I have had many teeners and put coolers onto all of them except 1
Sold that car instead

I have been tossing around the idea of adding an external oil cooler . At this time I am cautious because I don't want to damage the motor but at the same time I want to be able to drive the car to all the local events . What would be a sufficient amount of miles to be fully broken in? I am currently running first Castrol 20-50W racing oil but wanted to check my oil temp sender so I drained the Castrol but then couldn't find it again so the motor now has Valvoline 20-50W racing oil . I posted a while back a photo of Mobile1 synthetic oil for older cars that need zinc . I might buy some and change the oil again .

[bkrantz]

10W-30 might be too thin.

[Ron914]

Do you have the stock 200c temp sensor?

Yes I do .

The edge of the red zone is supposed to be about 300F.

You say you’re running 216F so there is a disconnect somewhere if you’re getting to the red zone in 30 minutes of street driving.

Get your smog test but you should get this figured out before extended driving.


See top right graphic for approx temperatures with 200c sender.


Does gauge work properly (ie all the way to the left when cold)?

Have you verified wiring? The wire from the sender should not have any DC voltage on it. Should be high resistance when cold and rapidly decreasing resistance as oil warms up.

What size oil pump are you running? Do you know your oil pressure?

Unfortunately I don't know what size oil pump was installed ,but I do know a new one was installed .
I don't have an oil pressure gauge but I did recently purchase one but need to get the dual sender before I can install it .
Hers a photo of the gauge without power on it and one with power (the car has been off and in the garage for almost two hours now .

[dtmehall]

what does your oil pressure run cold/hot, idle/at speed (~3000rpm)

and by type of oil, if available?

[Ron914]

what does your oil pressure run cold/hot, idle/at speed (~3000rpm)

and by type of oil, if available?

I can't answer the oil pressure question as I oi not have an oil pressure gauge installed in my car . The type of oil is 20-50W Vavoline racing oil w/zinc.
I purchased an oil pressure gauge but I still need a sender and then figure out where I am going to mount it .

[Superhawk996]

When the engine is cold (as in overnight cold) it should be just like you’ve shown below

So on a surface level - we know the gauge seems to have full travel.

When it’s cold and you first turn the key - the gauge shouldn’t be moving significantly. Ie should still look like photo below.

There’s so many variables here and some that are unknown (like oil pump size), etc. it may take a while to work through them.

What am I taking about:

Let’s say someone put a 30mm pump into the car, you’re running 20W-50 oil, and your bearings are fresh and tight clearance.

Result: you’re likely running enough hot oil pressure to be bypassing the oil cooler all the time. Oil will run hot.

I’m not saying this IS what is happening but it’s to give you context on why all the details matter.

Factory spec for oil was 30 weight. Don’t get sucked into the idea you have to or even should be running 20w-50 on a fresh rebuild during break in. The 20W number in 20w-50 refers to cold weather performance. It isnt that cold in CA for the 20W aspect to even come into play. Basically you’re running 50 weight oil.

At some point, you’ll have to start inspecting, measuring, and trying to control variables.

[dtmehall]

superhawk

are you discounting that oil pressure might be a relevant data point?

[Superhawk996]

superhawk

are you discounting that oil pressure might be a relevant data point?

Nope not at all. It’s important.

Excessive pressure just causes the bypass valve to open fully bypassing the cooler, and dumping excess flow back to the sump.

Would be awesome to just put a mechanical gauge on it if need be. Was just trying not to overwhelm Ron with all the variables.

[dtmehall]

(IMG:style_emoticons/default/agree.gif)

[Superhawk996]

Posting this just for clarity on how temperature, pressure, and viscosity affect flow through the oil cooler and also where the oil pressure is measured in the oil circuit.

[Dave_Darling]

The temp gauge on the center console is not super accurate. It gives you a good idea of trends, but is not necessarily the best source of absolute temperature information.

If your turkey thermometer is reliable, 216F is absolutely fine. 220F is also just fine; it's when the oil gets over 230F that it's time to be concerned--and over 250F for any longer amount of time is a problem.

Remember that testing of oil at "operating temperature" is done at 212F. And at that temperature, the water will outgas from the oil rather faster than at 180F.

--DD