Engine Oil Too Cold

[dan.1337]

I have a Greddy/Grex thermostatic oil block adapter hooked up to a Mishimoto 19 row oil cooler in my R33 GTS-T.

The oil cooler is located in the drivers wheel well with ventilation cut into the splash guard to pull air through it.

The issue I'm finding is that my oil temps are very low. On track they sit at 85-90C (previously 120-130C), and on the road in winter they are sitting anywhere between 20-40C (previously 80-90C) with ambient air temps of 8-10C.

I paid extra for a thermostatic adapter so I wouldn't have these issues, but have a feeling it could be stuck open.

Does anyone have any ideas on how I can get my oil temps higher or test the adapter? I don't want to make covers for the cooler as the adapter should be doing this job.

[Jazzadub]

You could run 0-30W? It would be at the right viscosity at the track, and wouldn't be too thick at 20C to be a problem but definitely not ideal.

I think you have already tested that the thermostatic valve isn't working, otherwise your oil temperatures should sit at around the opening temperature when idling, just like how a coolant thermostat affects the water temperature.

It may be possible that the lines are not connected properly, ie the cooler is not actually connected to the thermostat ports on the sandwich block?

[MrStabby]

AFAIK oil pressure the key thing, but yeah 20-40 seems too cold. My HKS kit, which has a thermostat, sits at just above 70 degrees on the stock gauge all the time except at the track. To test coolant thermostats you just put them in a saucepan of tap water on the stove with a thermometer and check the temperature when you see it open. No idea if you could do similar with your oil thermostat, but if its stuck open you should be able to see that when you pull it out.

Agree with double checking the plumbing too.

[Dose Pipe Sutututu]

Are you still running the factory water/oil heat exchanger? If not I suggest you do as it keeps the oil temp in line with the water temp.

[GTRPSI]

Are you still running the factory water/oil heat exchanger? If not I suggest you do as it keeps the oil temp in line with the water temp.

This is a very important thing, not only does it pull heat out when hot but it also speeds up getting oil temps higher when cold.

Key point being you want oil and water temps about even.

Im surprised by the amount of people who remove them and just run a external cooler, with or without a thermostate, the factory heat exchanger will help warm up the oil quicker.

One cheap way to know if the thermostate bypass is open is to feel the feed hose to the cooler on a cold day, if its warm and the return pipe is cold, you know its stuck open.

[Dose Pipe Sutututu]

^ yep I cringe when I hear/see people doing it to their built motors!

Then they will say "well just baby it till it gets to the right temp" during that time most of the west and tear is happening but each to their own right?

[scotty nm35]

Oil thermostats are designed to 'Leak' oil to the cooler, they never seal completely so the cooler remains warm, to reduce thermal shock when the thermostat does open.

I would be leaving the water to oil cooler in place as has been mentioned.

[dan.1337]

Thanks for the feedback so far. Pulled out the thermostat to have a look last night and couldn't find anything wrong. The pin inside isn't stuck (was able to move it with a flat screwdriver).

I was using a 10w-50 oil but have just put Penrite 10w-40 racing in, so hopefully it's a bit thinner at lower operating temps than the 50 weight.

Still using the factory oil/water exchanger as I didn't want to tinker with this and run a pure oil cooler setup. Water temps are around 90C on track but can't remember what they are on street, I think around 80-90C according the the PFC hand controller.

Some pics of the adapter I took yesterday:

[scotty nm35]

Same one I have on mine, notice the piston is slightly open?

[GTRPSI]

What brand is it?

I think mine was closed when i tested it, if slightly cracked open it could be a air bleed function so you dont end up having it open and a buch of air enter your motor when you needed oil.

I might get it out tomorrow and take another look, its packed in a box somewhere....

Edited July 11, 2014 by GTRPSI

[scotty nm35]

Grex. I have a new one here also, both stay open slightly.

[Piggaz]

^ yep I cringe when I hear/see people doing it to their built motors!

Then they will say "well just baby it till it gets to the right temp" during that time most of the west and tear is happening but each to their own right?

RB 20's don't have a heat exchanger like the 26's do. They seem to be going ok for the last 25 years.

[scotty nm35]

They don't have a big front mount oil cooler from the factory either.

Evo's do, and they have an oil thermostat.

[dan.1337]

Same one I have on mine, notice the piston is slightly open?

Does your oil temp run cool on cold days even through that small gap?

[Dose Pipe Sutututu]

Does your oil temp run cool on cold days even through that small gap?

Mine is always around 5 to 10 degrees cooler than the water temp on normal days. On the track it's usually in sync

[scotty nm35]

Does your oil temp run cool on cold days even through that small gap?

I have a 30 row oil cooler with a 14 inch thermo that switches in automatically at 80c, I also run the stock water to oil cooler.

Most of the time my oil sits around 70 - 80c, even in winter, but I still got the oil up to 140 odd at Sandown on a 30 degree day, after only 3 laps. The water was at 145 though, I probably should have turned the boost down.

[BlackBox]

I am about to install a grex thermostatic oil cooler on my 34gtt,

Where is this stock water-oil heat exchange? Want to be sure I don't remove/alter it

[Dose Pipe Sutututu]

I am about to install a grex thermostatic oil cooler on my 34gtt,

Where is this stock water-oil heat exchange? Want to be sure I don't remove/alter it

it's where the oil filter sits on.. you'll see water hoses going in/out of it

[Chris32]

Interesting, I can't see how your oil can get that cold. My car runs a similar sized cooler in the same location without a thermostat and my oil gets up to around 70 in a few kms and settles at 80 for the rest of the drive / until you give it a sustained bootful. Running the Penrite Racing 10 too.

What sort of gauge are you running and where is the temp sensor located?

[Dose Pipe Sutututu]

Interesting, I can't see how your oil can get that cold. My car runs a similar sized cooler in the same location without a thermostat and my oil gets up to around 70 in a few kms and settles at 80 for the rest of the drive / until you give it a sustained bootful. Running the Penrite Racing 10 too.

What sort of gauge are you running and where is the temp sensor located?

It's because you're still running your stock water/oil heat exchanger

My oil temp probe is in the sandwich/thermostat plate

If you ever see guys with RB20s with massive oil cooler without thermostats - their oil takes ages to heat up.... (I for one did the same thing on my RB20 back a decade ago, ran an oil cooler without a thermostat - very silly).