Overheating Motor

[redlightningsvx]

Well I when in town today about 1:00pm to the skatepark about 15 miles away. About 30min later I dive about 2 miles to my buddy's work to pick him up and waited for about 5-8 min with the a/c on full 65 blast. After that we drove about another 2 miles to his house and I sat about another 5 min in the car, a/c still running. Then the a/c get warm and I look down at the temp gauge and its about 1/8in away from the top line. I then quickly shut it off and checked everything under the hood. I then started it back up and cranked the heat on which cooled it back to normal operation temp. We then drove about 2 more miles to the skatepark and I left it sit. At about 8:30pm I started the car and cranked the a/c on again full blast to try and simulate the heating problem....nothing happened. So I drove about 15miles back to my house a/c still on and not a single problem. This didn't happen before today. The only thing I touched on the car yesterday was an oil/filter change, removed the muffler which is still off the car, and I checked the tranny/coolant lines for cracks. I squeezed the coolant lines a little top and bottom and I think some how I may have damaged the thermostat. So what do you guys think, just PLEASE DON"T SAY HEADGASKETS.

[Hocrest]

It's your headgaskets...

Just kidding untill we know more?? Did you check the fluid when it cooled down? Do both fans work? If it just happened the once, it could be a thermostat? Keep an eye on it and check the fluid regularly. If you have to keep adding and you can't find any leaks, then it could be your... I won't say it...

[redlightningsvx]

You scared me Yes both fans work and when it cooled down the overflow tank was at full but when I opened the radiator cap I didn't see any fluid? Both rad hoses are hot. Also it rose temp while driving to the gas station ealier today to. it like when the a/c works the heat is cold and when the heat works the a/c is warm.

PS: both rad hoes felt like they have a lot of pressure in them.

[Wikedjuggalo]

When in doubt... replace the thermostat.

[redlightningsvx]

That's what I hope it is. I think when I squeezed the rad hoses I may have damaged the t-stat.

[Crazy_pilot]

My car overheated on the highway back in May. I topped up the coolant, drove it the remaining 13 hours of my trip, and continued to drive it all summer without the gauge ever going past the little squiggly lines of the temp logo. I replaced the water pump and thermostat last week when the pump started leaking. Maybe our cars are just getting a little cranky in their old age?

[Hocrest]

Originally Posted by redlightningsvx

That's what I hope it is. I think when I squeezed the rad hoses I may have damaged the t-stat.

I really doubt that you damaged the thermostat by squeezing the hose...

Also make sure that there is good flow into and out of the reservoir. Pull the small hose off where it attaches to the radiator and blow through, it should bubble into the reservoir with little resistance, then blow into the reservoir and you should get good flow back out.

[redlightningsvx]

Dave, I just opened the rad cap and I seen a little coolant in there now. About enough to be level with the fins in there. I also disconnected the hose on the cap and blew into it and it felt like it may have been blocked because it took a good quick blow and it bubbles with ease now. Also the coolant level in the overflow tank ia about a 1/4 in past the full line so that may be where the rest of the coolant may be since the tank isn't full?

[svxcess]

Originally Posted by redlightningsvx

I also disconnected the hose on the cap and blew into it and it felt like it may have been blocked because it took a good quick blow and it bubbles with ease now.

I would take the reservoir out and clean it thoroughly inside.

There still may be some sort of debris at the reservoir opening where the hose connects. While this may allow the coolant to pass from the radiator to the coolant tank as the engine gets hot, it may also plug up the hole so that when the engine cools, the fluid is not able to be drawn back into the radiator.

I've been down this road this week with OT...

My overheating may be a head gasket as well. As a temporary fix, we drilled 10 small holes into the thermostat, removed the "jiggle" pin, to allow for better coolant flow. Also added a new radiator cap (my other one would not allow the fluid to return to the radiator after cool down-- a collapsed top hose is a sure sign)

Things are back to normal for a few more months.

Also running about 3O% antifreeze/ 70% water (with Water Wetter) to improve cooling characteristics. DEI Radiator Relief from Summit Racing is another good product. Comparing it to Water Wetter, it does not foam up when you shake the bottle.

See video HERE

.

[redlightningsvx]

Thanks for the advice John. I'll definatly clean the tank and hose tomorrow as the inside did look a tad dirty. As far as coolant i'm running Subaru long life coolant 50/50.

[kwren]

If the coolant is low... down to the fins... the car can overheat at low rpm's when it is up to normal driving temperature to start with, and you have a hot day and use the air-conditioner. Increasing the rpm should bring the temperature down but those little radiators need to be full of coolant.

Keith

[Hocrest]

Originally Posted by kwren

If the coolant is low... down to the fins... the car can overheat at low rpm's when it is up to normal driving temperature to start with, and you have a hot day and use the air-conditioner. Increasing the rpm should bring the temperature down but those little radiators need to be full of coolant.

Keith

Yeah, and if the hose to the reservoir was blocked, it could cause an air bubble in the system. Clean out that tanks and make sure you get the air out of the system.

With the car cool and slightly uphill (or on ramps) start the car with the rad cap off, top off the rad with water and run untill it gets up to temp. The fans will kick on and the thermostat should open, you'll notice that the coolant starts circulating more. Keep adding water to keep it topped off, then put the cap on and turn off the car.

[SoCal LS-L]

Originally Posted by redlightningsvx

Thanks for the advice John. I'll definatly clean the tank and hose tomorrow as the inside did look a tad dirty. As far as coolant i'm running Subaru long life coolant 50/50.

Quick trick for cleaning the reservoir tank. Its counterintuitive, but dump out the reservoir and add small gravel and rocks into it, enough to make it 1/4 to 1/3 full. Put in a little dish soap, a little water, and shake the hell out of it.

The coolant deposits are hard as hell to clean off the sides in there, but do this and it will scrub the insides clean and bright. Afterwards simply dump out the rocks, rinse the inside fully, and viola!

[redlightningsvx]

Thanks for the advice so far. Thankfully it isn't leaning towards the headgaskets yet.

[SSSVX]

Lot of good advices. Hope you can take care of this overheating.

Btw, How many miles on your water pump already?