High Oil Temps with Paxton or TT?

[Viper X]

Hey Paxton or TT Guys,

What are your oil temps;

1) At idle when warm
2) Cruising
3) Running it hard

Anyone have any failures of the factory oil cooler?

I'm having issues and can't seem to figure it out.

Coolant temps are normal, 185 to 190 F at idle on a warm - 80 F - day while oil temps are 225 to 240 F.

Input appreciated.

Dan

 

[Kenneth Krieger]

Have a Paxton, and no issues at all with oil temp, even living in Phoenix with 115 degrees in the summer. My oil temp and coolant temp are virtually the same at about 200 to 205 tops. The discrepancy in your oil temp being so high compared to your coolant temp tells me you may have a problem with your oil cooler, or possibly a kinked oil line, or even a bad oil temp sensor.

 

[repiv]

Have run both TT and a paxton car in Las Vegas, no high temp oil issues at all, idle or under boost.

 

[Viper X]

This car is heavily modded, equipped with a triple pass radiator and Evans Cool coolant. High oil temps occur at idle and in stop and go traffic. Temps come down slowly at speed to more normal levels.

 

[SnakeEye]

This car is heavily modded, equipped with a triple pass radiator and Evans Cool coolant. High oil temps occur at idle and in stop and go traffic. Temps come down slowly at speed to more normal levels.

Did you speak with Dan Cragin yet?

 

[Viper X]

Yeah,

We're still scratching our heads trying to figure this one out. I'm going to swap thermostats tonight or tomorrow as we just replaced it. Perhaps it is sticking on the housing.

Dan

 

[Viper Specialty]

I would lean towards either a defective heat exchanger (doubtful), or more likely, somehow the coolant flow to the heat exchanger is obstructed. I would look first at coolant line routing, make DAMN sure the lines are routed correctly. Next, check flow through the exchanger and all lines connected to it. (This includes the heater core! It could just as easily be an issue there!) Lastly, check the water pump for an impeller going south, as this may slow coolant flow down, but not enough to impact engine cooling drastically. last on the list would be to swap the heat exchanger with someone elses and/or bypass the heater core. Maybe it somehow has a coating or corrosion on the internals preventing heat transfer, or possible core damage/obstruction.

Highly doubtful on the T-Stat. You would have to see your engine temps rise first, as the coolant routing for the Heat Exchanger is contained entirely upstream on the raditaor and T-Stat.

 

[ILLSMOQ]

It was cool today but my oil temp got no hotter than 15 degrees over the coolant temps after a longer seeion of spirited driving.

-Kurtis

Hey Paxton or TT Guys,

What are your oil temps;

1) At idle when warm
2) Cruising
3) Running it hard

Anyone have any failures of the factory oil cooler?

I'm having issues and can't seem to figure it out.

Coolant temps are normal, 185 to 190 F at idle on a warm - 80 F - day while oil temps are 225 to 240 F.

Input appreciated.

Dan

 

[GR8_ASP]

My oil temperature rises a bit quicker than before the Paxton, but rises to the same point unless I am using running high rpms. Remember that supercharger temps, thus leading to supercharger heating of the oil, is rpm related and not boost related. Internal engine heat is boost and rpm related. When under boost a lot, like at a track day, my oil temperature rises well above the coolant temp. On the street I typically see the oil temp at coolant temp or slightly higher. On the track I have seen it climb to 240-260. That was also when I started to get oil pressure problems before I installed Daniels swing arm oil pick-up. Since then the temps have been the same but the sudden drop in oil pressure is gone.

If you are seeing very oiil temps on the street I think something is wrong. Either on the heat rejection side as mentioned above or on the heating side (like a supercharger bearing going south). I can tell you my Paxton is much more noisy now than it was early in life. Seems that after 10,000 miles it started to get quite a bit noisier. I assume that is the supercharger bearings in some way but have no way of knowing. Anyone know if the bearings in the Paxton are replaceable?

 

[Viper X]

Daniel and GR8_ASP,

Thanks for responding. No blockages. Hoses routed correctly (I have a 2006 SRTC that is still stock to use as a reference).

Here’s the latest. I thought that some of you’d want to know.

I spent the weekend testing and re-installing the big old oil cooler (air cooler mounted in front of the radiator).

During the testing, I found that the coolant was actually heating the oil. With the car running at idle for about 30 minutes, coolant temp 185 F, 70 F air temp, the oil temps from the engine into the OE oil cooler were 176 F. The oil temps coming out of the oil cooler were 216 F.

The coolant temp (taken with an IR gun at the coolant feed line) was about 215 – 220 F.

Bottom line, the oil cooler works well as a heat exchanger; the coolant running into it from the engine was just too warm to help cool the oil and actually heated it.

I theorize that the Stryker heads remove more heat from the engine and transfers that heat into the cooling system right where the oil cooler feed line attaches. Unless my engine block has been modified (not likely), this could be a concern for anyone installing Stryker heads on an SRT-10 and utilizing a larger radiator.

I also theorize that the triple pass radiator that I installed slows the coolant flow down enough that this “coolant warming the oil issue” can be a problem at extended periods of idling in stop and go traffic on a warm day with the Stryker heads.

AFTER re-installing the big "air" oil cooler, oil temps came down to 170 – 180 F running the car at idle and while driving conservatively, lower while driving.

I tested the 180 F thermostat (that was in the engine previously) and the 170 F thermostat (that is in it now). I found that the 180 F thermostat installed with the engine rebuild did not fully open, even at 212 F. This is likely why my engine has run warm since the first engine rebuild. I could have saved myself a bunch of time and trouble by just checking and changing the thermostat first (isn’t hind sight great!).

The 170 thermostat opened fully at about 180 F and works as it should. The rear “opening” portion of the thermostat was a tight fit in the thermostat housing, so I polished the edges of the housing with emery cloth to allow the T-stat to open easier.

Oil cooling is no longer an issue.

On the subject of my water pump wearing out, it's possible, not likely. Last night on the freeway at 80 mph with an air temp of about 60 F, my coolant temp reached and remained steady in the 130 F range. Too cold. (Oil temps were 170 F). I could nudge it up to about 133 F by running in 5th gear, but that's all.

It's much easier to put the heat back into this car than it has been to take it out.

Dan

 

[Kenneth Krieger]

Thanks for the update.......that will probably help someone else out in the future.

 

[Bolt]

Excellent update Dan! Thank you for the details!

 

[Viper Specialty]

Hey Dan-

One thing just crossed my mind. Has this car ever had "green" coolant in it?

If I also may make the suggestion, a nice set of head coatings (chambers/valves/ex. runners) will cut down on heat transfer into the heads considerably.

 

[Viper X]

Hi Daniel,

No green coolant has ever been in these heads. The block had the factory fill, which I think was orange.

The Stryker heads have had only Evans waterless coolant in them for the last year or more since the rebuild. I am now running Mopar Orange coolant with an anti-rust additive. This orange coolant seems to work better at transfering the heat than the Evans did.

Never thought about coating the inside of the heads.

Dan