Discussion Forum - Northstar Chevelle Club

SShink · 3K+ Club

Successful weekend working on the Colorado

John D · 2K+ Club

Reminds me of a story my Dad used to tell... about (of all things) the Muntz Jet.

On the (few) cars that made it to needing a tune-up in the Chicago area, there was a minor design flaw... didn't matter if you had Ford, Lincoln, or Caddy power - you couldn't get to the spark plugs! He used to take a 1" holesaw and punch 4 holes in each fenderwell. Pull the wheel/tire and with a long extension & a few swivels you could get the plugs out.

SShink · 3K+ Club

John D wrote:
Reminds me of a story my Dad used to tell... about (of all things) the Muntz Jet.

On the (few) cars that made it to needing a tune-up in the Chicago area, there was a minor design flaw... didn't matter if you had Ford, Lincoln, or Caddy power - you couldn't get to the spark plugs! He used to take a 1" holesaw and punch 4 holes in each fenderwell. Pull the wheel/tire and with a long extension & a few swivels you could get the plugs out.

I had to pull the wheel and inner fender on my son's '02 Ford Escape just to change out the front turn signal bulb, and that was the factory R/R method. Of course, 2 weeks later the other side bulb went out, and I had to do it all again on the other side.

Lost in the 60s · President

SShink wrote:
-Did some research on why the check engine light was coming on with P0128 code, which said the engine temp was too low and either a bad temp sensor or something with the cooling system. Looked like the common issue was a defective thermostat, so looked it up and found a video on You Tube that showed a slick way to replace it by taking off the drivers wheel and an inner fender shield, then accessing the lower radiator hose and thermostat housing on the engine through the side. It went pretty well and other than a little dexcool on the floor, 45 min. later the old was removed and the new installed. Now instead of the temp running just over 1/4 on the temp gauge, it's now just over 1/2 on the gauge and the heater air is a LOT hotter.
I'm hoping the mileage improves since it wasn't operating at the optimum temp too. I checked before and it was 17 mpg combined, so hopefully this will help.
Oh, and since it was 66 degrees yesterday, I changed the oil and filter in the Chevelle. Put the battery tender and car cover on it for the next 2.5 months until the next drive in March.

I keep looking at this pic and the lower hose can't be the return like we are used to with the thermostat there. I'm thinking it has to be the pressure side to heat the thermo up to open. Does the pump circulate the water in the opposite direction than "normal " ??

The pressure side of the heater always comes out of the block too and returns to the pump, or maybe radiator.

SShink · 3K+ Club

Lost in the 60s wrote:

I keep looking at this pic and the lower hose can't be the return like we are used to with the thermostat there. I'm thinking it has to be the pressure side to heat the thermo up to open. Does the pump circulate the water in the opposite direction than "normal " ??
The pressure side of the heater always comes out of the block too and returns to the pump, or maybe radiator.

I'm not sure Mitch, but it could be reverse flow like the SBC serpentine systems. Chris P. would probably be able to answer that one.

The thermostat is a cast aluminum assembly that cost $40 at O'Reilly's that is the thermostat mounted into the housing and partial tube. Gone are the days of replacing a $3 thermostat and gasket to replace them...

Lost in the 60s · President

That's nice that you had to buy the whole assembly...

Notice any improvement in performance or mileage yet ?

SShink · 3K+ Club

Lost in the 60s wrote:
Notice any improvement in performance or mileage yet ?

Just filled up the tank Monday night and reset the trip odometer, so will check on the next fill up. So far, the needle hasn't moved after driving to work for 1.5 days, so will see. It seems to have more power and take less throttle, so hoping it's running better. The heater is sure working better, so I know there's better coolant flow and the needle is now slightly over half on the temp gauge and it was only at 1/4 before changing the thermostat.

67ss · 1K+ Club

Most new GM vehicles uses the return from the heater core dumping on the thermostat to get them to open up. We see plugged heater cores cause engine overheat because the stat does not open once in awhile.

SShink · 3K+ Club

67ss wrote:
Most new GM vehicles uses the return from the heater core dumping on the thermostat to get them to open up. We see plugged heater cores cause engine overheat because the stat does not open once in awhile.

Hmmm... anything to do with that lovely orange Dexcool coolant GM uses that I've heard can gum things up? I had to add some Dexcool into the system to replace what I lost replacing the thermostat.

Lost in the 60s · President

67ss wrote:
Most new GM vehicles uses the return from the heater core dumping on the thermostat to get them to open up. We see plugged heater cores cause engine overheat because the stat does not open once in awhile.

That sounds like a dumb engineering design...

Stan if you had said you were panning to replace the stat, I would've suggested back flushing the heater at that time. The heater plugged on my 2000 K1500 a few years ago and I was reading what a nightmare it was to replace. Then a guy on Full Size Forum, said he just back flushed his and it worked again. I disconnected the hoses at the engine and held the garden hose on the outlet hose and sure enough, a bunch of "gunk" came out the inlet hose and once I was sure it was all flushed out, I refilled what had been lost and it worked great from then on again.