Still having coolant temp issues with LSJ

**RyanD** · August 12, 2013, 04:05 PM

If I remember correctly, there are two coolant temperature sensors on the LSJ. The temp sensor that goes to the dash is reading as high as 220F while the temp sensor that I'm reading from the ECU with an AeroForce gage is 170-180F. If I shut the engine off, they both read the same temperature. If I rev the engine, the temp on the dash goes down some.

I'm guessing I still have an air pocket at the sensor? If so, I've done everything I can think of to get the air out. I've heat cycled the engine many times, put vacuum on the system, put pressure on the system, and I drilled a small hole in the thermostat. Any ideas?

**Positron** · August 12, 2013, 05:20 PM

One is before the rad and straight out of the head, worst case scenario the other after the rad, sounds normal to me. LSJ has a goofy way of having TS after the Rad.

I put a remote TS before rad, resolved all those issues.

**MadMaxAtom** · August 12, 2013, 05:28 PM

^What Posi said; goofy T stat configuration. I solved it by removing the T stat completely...engine warms up fine,runs 175-190 and won't go over 200 on the hoottest of days.Plus,with the T stat removed,the system purges any air out with ease. Win-win!!

**Positron** · August 12, 2013, 06:20 PM

Originally Posted by MadMaxAtom

^What Posi said; goofy T stat configuration. I solved it by removing the T stat completely...engine warms up fine,runs 175-190 and won't go over 200 on the hoottest of days.Plus,with the T stat removed,the system purges any air out with ease. Win-win!!

E85 no likey that cold.

//TJ Hey Mark I get the blue rails now!.. at least I didn't eat one like Jeff Gordon this weekend.. //TJ off//

20130521_WGI_BLU_2060.jpg

**RyanD** · August 13, 2013, 08:10 AM

When I first put the motor back together, I had an air pocket near the sensor that got hot and blew a hose off. I never had a problem with the temperature before I pulled the engine, so I think there is still something wrong. Maybe I'll try running it without the thermostat in to see if that makes a difference.

Is the seal for the housing separate from the thermostat? I can't remember if it's part of the thermostat or not. Can I just take it out and put the housing back together?

**Positron** · August 13, 2013, 12:16 PM

Ouch that's a good way to bust a head.

I don't care to run wide open with a missing TS no good way to seal the housing and it'll flow too much water and run hotter.
I'd drill a couple holes in the TS, will verify theory and cheaper to undo.
But I don't think that's your problem. Did you plug off heater ports?

**MadMaxAtom** · August 13, 2013, 12:27 PM

There is no thermal shock running without a thermostat,as the entire system raises evenly in temp as the engine runs and the system circulates.None of the system is isolated. The temp heats up into the 175-190 range within 2-3 minutes,and never goes above 200 degrees,even on the hottest days at WOT for 40 minute sessions. Try it..you will like it!
I cannot take credit for coming up with the idea of running no thermostat; I copied what most of the off road Pro race buggies guys are doing,that run the Ecotec; they learned to eliminate the T stat with no issues,and the best part is no more air pockets either. It really is an accepted practice with people who race the Ecotec.

**RyanD** · August 13, 2013, 01:14 PM

I could replace the thermostat with a restrictor like this.

Amazon.com: Mr. Gasket 6126 Water Outlet Restrictor 90 Degree Plate Kit: Automotive

**MadMaxAtom** · August 13, 2013, 01:42 PM

Try it with the T-stat out. Yes, I am well aware of the arguments against removing T-stats; engine runs too cool and uses excess fuel; Engine coolant circulates so fast it cannot transfer heat..etc etc etc... However,the Atom is quite unique in it's ultra-long coolant loop up to the smallish radiator and then back to the engine,that it actually runs very nicely with NO thermostat. It does NOT run cold, and it does NOT overheat.Bleed the air pocket off the top of the radiator,and it won't air lock either (unless you lose coolant) It really does run 175-190 degrees normally,and out on track,it will stay below 200 degrees! Try it..and report back,before dismissing a simple solution. It worked for me,in more than one Ecotec Atom.

**Positron** · August 13, 2013, 04:57 PM

We'll have to disagree on that one as that was not my experience and I have as many laps as anyone with this motor.

So how do you seal the housing since the seal is on the TS?

Besides my beer says this is not his problem anyway but I've got no dog in this fight.