coolant change/flush

On my way home from work one night my car (Saturn SC1 1.9L SOHC) all of a sudden overheated. The hoses weren't even that hot. The lower radiator hose was actually cool to the touch. Finding out that the thermostat was by the lower radiator hose, I figured that the thermostat was stuck closed. I made it home and parked it for a week. Just started it today to go pick up some parts down the road at NAPA and when I turned the key the temperature gauge was still really high. I bought a new thermostat and an ECTS. I took the old ECTS out and the tip was melted completely gone. It was amazing. So I replaced it. I drained the coolant and ran hose water through the engine block where the upper radiator hose connects until the water came out of the engine clear. I cleaned out the overflow jug. I ran water through the radiator until it was clean, I also cleaned the fins with the garden hose (I took the radiator out). I was wondering if I still need to flush the heater core. If I do, how could I easily do that? Also, I have heard a lot of bad things about the Dex-Cool antifreeze as far as it crystallizing under gaskets and causing head gasket leaks. Would it be a smart idea to put the green antifreeze in it instead? Thanks!

Wow youve done alot!

Year of the car tho?

You should be alright with either antifreeze. With all the saturns ive had i havent had any problems with any specific type of antifreeze.

Also, the heater core is inside the cabin. Its quite a pain to get to, but i really dont think its needed.

Make sure your fan turns on. Also make sure it turns on when the car gets hot.

It's a 2001. Can't believe I forgot to mention that. I did get the heater core flushed today. I got the heater core hose that connects to the intake off and sprayed a garden hose through it and watched it flush out the engine plug until it got clear. Unfortunately that hose is so hard to get to I couldn't get a good grip of it to break the seal so I had to cut it. That is one hard part to find too, the little hose from the intake to the heater core. The car is all back together except that hose and the antifreeze. I had to buy a new drain plug for the radiator too. Damn plastic parts! It was quite an experience taking apart everything. I've never done a coolant flush before. I'll keep this updated when completed. Thanks!

Glad you got it flushed. Yes getting back there is quite a pain! You may want to unto the top mount of the engine and push the engine forward so you have more room if your working from the top.

Also, junk yard is the best place to get that part. and the cheapest.

Also, once done be sure to make sure the radiator fan works. that is important.

Also, once done be sure to make sure the radiator fan works. that is important.


The fan should automatically turn on when the A/C is on, correct?

Correct

So I ordered a hose from Advanced Auto, pick it up at the store and it's similar, but not exact. I tried to get the hose on the manifold side and the hose was too small, it would get on there but would not move up for the life of me. So I took the old hose that I cut off, cut the end back and put it back on. Luckily it had enough slack which sucks because I didn't think about doing that in the first place. Anyways, I put antifreeze in, which I couldn't believe didn't even take two gallons, and ran the car for awhile. I turned on the A/C to make sure the fan worked, which it did. I drove the car around for awhile just to make sure the antifreeze got settled enough through the system. One thing I realized is that the lower radiator hose never got warm. I replaced the thermostat. When the radiator was off I sprayed into the lower radiator hose area and the water came out the other side which tells me the radiator isn't plugged. I don't know what else could be causing the lack of coolant through the lower radiator hose. Any ideas would be fanastic! I don't want to take it on my hour trip to work yet until I'm sure everything is in working order. Thanks!

The lower radiator hose SHOULD be cool. The upper hose should be VERY HOT.

Normal operating temp for your car should be 1-2mm past 1/4 as per the gauge. fan turns on at 3/4 as per the gauge

I think your good to go :)

The lower radiator hose SHOULD be cool. The upper hose should be VERY HOT.

Normal operating temp for your car should be 1-2mm past 1/4 as per the gauge. fan turns on at 3/4 as per the gauge

I think your good to go :)

So I drove the car into town to see my grandma, about a 45 min drive one way. The temperature that the car stayed at per the gauge was just under half, which is a little warmer than usual. After the drive in, I noticed the car started leaking antifreeze on the ground slowly. There was a pretty good puddle underneath the car by the time I left. I can definitely tell it's antifreeze, but I couldn't see where it's coming from. The heater core hoses were dry, the upper and lower hoses were dry. I'm going to put it in the air as soon as I can to see where this damn leak is coming from. How frustrating!! All that work and the damn thing leaks. Since the car heated up so much when it first overheated, could the head gasket be leaking??

Unfortunately its plausable.

How did the car drive? did it run ok? Any difference from earlier days?

Check the water pump. Check all your hose connections

Unfortunately its plausable.

How did the car drive? did it run ok? Any difference from earlier days?

Check the water pump. Check all your hose connections


I finally got a chance to check this out and go figure!!!! It was the heater core hose that was leaking, it wasn't tight enough. The leak wasn't visible from the above. So I tightened it and it seems good to go. I think I got a thermostat that is a higher temperature though because the normal operating temperature now is just a little below half now, I don't remember it being that high before. Well, I will be taking it to work tomorrow, 1 hour drive each way. That should determine whether or not this things is ready to roll. Thanks for the help!!!!

normal operating temperature now is just a little below half

Should be 1-2mm above 1/4 for you. IIRC they do sell a 205F. OEM is 195F. It wont hurt anything though! You may possibly see a SMALL decrease in gas mileage but that can be compensated with a good said of tires.

I apologize for my last post. It was COMPLETELY off. I didnt read your post thoroughly. No way would a head gasket be the suspect for what you described. After re-reading it again now, a leak hose or connectoin (since you just worked on the connections) was the number one suspect.

Glad you got it fixed tho!:biggrin: