Poor flow to front cooler
 

My car hasnt been running as cool as it used to, and this summer it got hotter than i am comfortable with. After driving it, the line going to the cooler is hot but the return line isnt. Mocal thermo and cooler mounted in RS bumper.

Either the thermostat is opening just enough to heat the oil in the line, or the cooler is blocked up somehow and nothing is getting through.

Which is more likely before i make a huge mess in the garage?
I would think the thermostat is Eff'd up somehow.

Paul

This is a subject that has been addressed recently a number of times.

Check your bronze oil lines from the thermostat up to the cooler. Is there an obstruction? No, I don't mean a huge crimp, just a moderate dent or something that might have made you think "No big deal, the oil can certainly push past that."

Fact is, the oil can push past it a little bit--enough to heat the line to the cooler but not enough to push through the cooler's more restricted tubing. So instead the oil bypasses back to the tank through the thermostat, seeking the path of least resistance.

Check the lines first. They need to be near-perfect.

Paul:

If I may add,.......lose that Mocal thermostat.

Its bad news for these engines. Use either the factory ones or the Troutman ones that use the Behr factory element. Leave the Mocal units for non-911 applications. :)

These factory ones have a pressure relief function that the Mocal's don't have. This ensures oil flow to the engine during periods of high demand and if something becomes obstructed.

Formerly Steve: i should have been more specific, i have AN lines front to rear with no crimping .

Steve W: Thanks for the heads up, I guess i'm in the market for a nice used factory thermo.

Paul

I got one (used) for a very reasonable price from Dan Petchel @ Cars Inc.

Whats resonable? email me if you want.

If i use a factory thermostat will i need 4 adaptors for the threads to AN?

Paul

What size are your AN lines?
Is the cooler hot itself?
You can buy AN to factory unions for fairly reasonable $ from Patrick Motorsports. OR you can buy AN to metric fittings from Mocal in FL.
I'm sure other vendors sell those parts, Steve Weiner included.

Doug