RJ_RS_SS_350

I guess you zigged when you should have zagged. Hope you get back on the road soon with no more problems.

Oldblue

We'd cal it a T stat or stat.
The flush is easy, messy but easy, drain the coolant into a pan.
Fill rad with clean water run car two or three minutes, let cool and drain again.
Repeat.
While the cooling system is drained change to the correct ACDelco Thermostat,
Fill cooling system with 50/50 mix of Dexcool and distilled water.
Run engine for three or four minutes then turn off to allow any air to escape and cool, then top up the Dexcool mixture.
Start the car, turn the heat to full , drive around the block to allow to circulate the coolant.
Park the car front bumper higher then the rear, left it cool down, check the Dexcool level.

whopper

x2 what oldblue says on the coolant change.

If you have never done it before on the HHR, the drain spigot at the bottom of the radiator can be difficult to find - it's on the backside of the rad, on the passengers side close to the inner fenderwall - it's hard to see from the top, but can be found by feel. It's plastic so be careful with it, as they can be broken. If it won't come loose by hand, if one is VERY careful, a pair of pliers can be used (I think it's easier from the bottom rather than the top).

anthonybeatz22

Since Minneapolis right is experincing below zero weather, would there be any worries of the water freezing in those 2-3 minutes I first put the water in?

Also, could putting the wrong coolant in the HHR be enough to cause over heating and no heat or do you suspect something else?

Thank you.

Oldblue

Wrong coolant will cause these problems Dexcool and Prestone are not chemically friendly!!

Dbeluscak

Regardless of what a "term" is...a flush and fill is an easy procedure. Since I missed so much today I'll try and keep it concise. Unfortunately, I've seen temps in the 250-260 range. What that tells me is the damage is done. Probably not from mixing coolant types (been there, done that). What I would suspect is a blown head gasket. You can't expect it to stay in tact with temps that high. That's my suspicion, hopefully not the case.

In order to determine how bad it is you've got to get proper dexcool and a genuine GM thermostat. Not saying it's going to solve your problem, but as everyone has said. It's where we need to start.

The other issue you could have is the notorious air bubble. This was a thorn in my side for both HHRs I have built. If you fill up on level ground as suggested you will almost always end up with air in the system. What you have to do is make the fill cap the highest point in your system. This is easily achieved by putting it up on ramps or jacking it up. Fill as normal, get the nose in air, and bring the car to normal operating temp (180-190*) you're going to leave the fill cap off during this time. You'll notice it bubble all the air out. Once you've reached operating temp you can top it off and go for a test drive. I leave the overflow empty to see what boils out, if it needs coolant add to the fill line. Easy peasy!

If you have to add coolant after a few days it's definitely going somewhere. If it's not leaking and it isn't showing up in the oil. It's being evaporated by blowing by the head gasket and going out your tailpipe. Unfortunately I know from experience, this sounds exactly like my wife's SS. We had temps that would max out the gauge (250-260*)

Well...I did try and be concise. Hopefully this helps. If you'd like to take it on yourself a complete rebuild probably isn't necessary. You can tear the head off in the car and replace the gasket.

anthonybeatz22

Thanks for sharing this and for having detailed information about your experience. I really hope it isnt a head gasket, I really hope thats not it.

Today I am going to try and study how to do a radiator flush, and get a ACDelco T-Stat, and then we'll go from there, I see the head gasket parts for the HHR are fairly cheap, but based on what I'm saying it doesnt look the procedure is simple.

Another question, does Dexcool coolant come on a jug of its own? I see Prestone that has Dexcool in, and many other brands mixed with Dexcool, I'm assuming I should get one that only has Dexcool, not mixed with anything, right?

Oldblue

The 50/50 Dexcool is the easiest way to get the correct product, the brand name is a personal choice, Prestone, Peak, ACDelco are all good brands. The thermostat is the key, the off brands don't open in sync with the sensor which causes a code P0128. That why I strongly recommend the AC Delco thermostat, period!

firemangeorge

Dexcool is the formula name, not a Brand name. Many different companies make a Dexcool version of antifreeze.

Oldblue

This is the Dexcool produce I use


PrestoneŽ DEX-COOLŽ 50/50 Prediluted Extended Life Antifreeze/Coolant | PrestoneŽ


No mixing, no mess just pour it in the rad hose cap opening!!