3.6 SC conversion running hot

code7rpd · 01-14-2005, 01:06 AM

My 3.6 conversion has been running flawlessly and the only recent thing I've done is add Carrera kick panel blowers. I was driving around last week and noticed the car getting hotter than normal. Usually the oil temp gauge gets to about 212 and once the thermostat opens to the Carrera fender cooler and the Setrab nose mounted cooler the temp drops to about 190. It was getting up to 240 and not going down after driving on the freeway in about 45 degree weather. After checking the front coolers I found them cool to the touch. I figured the fender well mounted thermostat was bad and it was replaced. Now the car gets to about 230 and cools down to about 210. If I let it idle for a while it gets to about 240 before it starts to come down but never drops below 210 like it used to. It looks like it is running about 20 degrees hotter than it used to. The 3.6 is from a 993 and I use Mobil 1 oil (15W50) - Any suggestions on why it is behaving differently?
Any help would be greatly appreciated.

Mike Feinstein · Mike Feinstein's Garage

I'm guessing the temperature range of your new thermostat is different than the original one.

Jack Olsen · 01-14-2005, 10:00 AM

The new thermostat might not be opening fully, or -- although it's unlikely -- you could have an obstruction in the external oil line that got in there when the thermostats were swapped.

Moses · 01-14-2005, 10:10 AM

Maybe a kink in your oil line?

What have you decided on for brakes?

Lukesportsman · 01-14-2005, 12:10 PM

Did you check the water pump bearings?

I'm thinking something along the lines of Mike. Did you change brands? Is the new one possibly less than a true constant diameter throughout? Moses knows more than me, but I might think a kink'd line would prevent it from returning to a lower temp once reached. Have you checked for oil flow or pressure difference across these heat exchangers? I take it that there would be no reason to have a second thermostat in series, correct?

You might wish to simply eliminate the thermostat from the equation with a temporary bypass to narrow down the culprit. You'd hate to chase your tail to only find out it was something totally removed from the original equation.

Craig 930 RS · 01-14-2005, 12:20 PM

45 degree days on the Freeway and temps like that?
My nose cooler (mounted WAY too close to the front pan) + Carrera cooler = temps that high on hard use track days at 70 degrees.

You didn't mention if the coolers are hot/cold to the touch after the thermostat change -

Rouxzy · 01-14-2005, 01:15 PM

I've had the same problem with my 3.6 conversion. The temp guange shows hot but when I feel the pipes before and after the thermostat they feel just warm. Could it be a faulty sender?
Tom

Craig 930 RS · 01-14-2005, 01:27 PM

Light went on:

Did you change out the sensor on the engine????
This is a must.

code7rpd · 01-14-2005, 02:02 PM

The sender is new as is the gauge. The coolers do get hot to the touch now so I know that oil is getting there and I better check the flexible lines going from the Carrera cooler to front cooler to make sure they are not kinked. I will report back.

Moses - still haven't decided on brakes - did you?

Craig 930 RS · 01-14-2005, 02:04 PM

Code -

What yr is your car - and do you have a pic of the front cooler in its mounted position?

Bill Verburg · Bill Verburg's Garage

Are you sure that the sensor and gauge match?

Even w/ a smallish stock Carrera cooler a 3.6 will run cool on a 45&degF day.

The oem tstats all open at ~180&degF &#177

code7rpd · 01-14-2005, 02:08 PM

I'm pretty sure the sensors match - I bought the gauge kit from Pelican and the engine was running cool prior to last week.

Bill Verburg · Bill Verburg's Garage

Get a meat tstat w/ a long probe or a lab tstat to Xcheck the accuracy of the new gauge.

Moses · 01-14-2005, 02:45 PM

Quote:

Originally posted by code7rpd

Moses - still haven't decided on brakes - did you?

Yup! Believe it or not, I'm driving my car down to TRE for some suspension/brake upfixin'.

Hope you get thyis sorted out quickly. I have a long digital thermometer on a cable if you need to check your readings. Let me know.

code7rpd · 01-14-2005, 10:01 PM

Bill - where should I mount the tester - next to the stock sender?

code7rpd · 01-14-2005, 10:03 PM

Moses - if you don't mind loaning it to me or letting me drop by to use it I would appreciate it. What is TRE going to do to the suspension and brakes?

Moses · 01-15-2005, 05:16 AM

Quote:

Originally posted by code7rpd
Moses - if you don't mind loaning it to me or letting me drop by to use it I would appreciate it. What is TRE going to do to the suspension and brakes?

I'll dig it up then call you today.

I will be getting new torsion bars, Elephant Racing bushings, Brembo GTPs and new Fikse FM 10s.

Elfer · 01-15-2005, 06:26 AM

Manny...hope you fix that problem soon. As far as a tester, check out Costco...they're selling a digital pyrometer cheap.

code7rpd · 01-15-2005, 10:53 AM

Thanks Moses. Elfer - how much are the pyrometers at Costco. I was thinking of getting an IR temp reader. There is a Raytec MT4 on ebay for about $55.

rcwaldo · 01-15-2005, 11:01 AM

Quote:

Originally posted by Bill Verburg
Get a meat tstat w/ a long probe or a lab tstat to Xcheck the accuracy of the new gauge.

As Bill says, check the actual oil temp with another means. Sears offers a digital volt meter that has a temperature probe (thermocouple) feature. The meter is around $65 and includes the probe. There, of course, are other more expensive meter and probe modules (Fluke), but this is really the cheapest, most accurate method. I am not a big fan of IR temp probes for accurate temp readings.

Just get the cars temps up, and slide the thermocouple probe down into the oil tank. Not the most ideal place to take readings, but will give you an idea to how accurate you gauge reads..

Chris