Did full flush now engine overheating!!

**impalaws6** · 04-29-2015, 11:52 AM

Just did the full flush including removing the block bolts on both sides. I bled the system but there is something wrong. The engine begins to overheat and the coolant comes back through the fill hole. The thermostat is new and even tested it it works. Bled it a couple of times. The hose that goes from t-stat to radiator remains cool. Can anyone help? I am already going to miss work because of this.

**impalaws6** · 04-29-2015, 11:59 AM

I forgot to mention after the car gets hot there is a thumping sound coming from the radiator

***SMWS6TA*** · 04-29-2015, 12:11 PM

Sounds like you have air trapped in the system.

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Sounds like you have air trapped in the system.

**impalaws6** · 04-29-2015, 12:48 PM

Upper hose gets hot, lower hose by t-stat remains cool. I tried squeezing the hoses but still nothing!

***SMWS6TA*** · 04-29-2015, 01:16 PM

what temp is the t-stat?

Stock = takes about 195-200 to open.

165* T-stat = takes about 165-170 to open.

As long as you are not above 220 you will be fine, however if the bottom hose doesn't get warm within a few mins you need to shut off.

You could also do an old school trick with the t-stat. Take a small bit and drill a hole close to the inside edge of the t-stat that will allow coolant to still get by but not big enough to damage the t-stat.

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what temp is the t-stat?

Stock = takes about 195-200 to open.

165* T-stat = takes about 165-170 to open.

As long as you are not above 220 you will be fine, however if the bottom hose doesn't get warm within a few mins you need to shut off.

You could also do an old school trick with the t-stat. Take a small bit and drill a hole close to the inside edge of the t-stat that will allow coolant to still get by but not big enough to damage the t-stat.

**impalaws6** · 04-29-2015, 01:23 PM

Its a stock t-stat I put it in boiling water and opened up. I hope I didn't damaged anything since I did let the engine run more than a couple of minutes.

***SMWS6TA*** · 04-29-2015, 01:34 PM

do you know where the coolant cross over tube is on the front?

If so you can try to bleed some air out but loosening it enough to let the air escape but not enough that you can't tighten it again once coolant starts flowing.

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do you know where the coolant cross over tube is on the front?

If so you can try to bleed some air out but loosening it enough to let the air escape but not enough that you can't tighten it again once coolant starts flowing.

**impalaws6** · 04-29-2015, 01:37 PM

Originally Posted by SMWS6TA

do you know where the coolant cross over tube is on the front?

If so you can try to bleed some air out but loosening it enough to let the air escape but not enough that you can't tighten it again once coolant starts flowing.

- - - Updated - - -

do you know where the coolant cross over tube is on the front?

If so you can try to bleed some air out but loosening it enough to let the air escape but not enough that you can't tighten it again once coolant starts flowing.

Should the car be on when I do this?

**Firebirdjones** · 04-29-2015, 02:53 PM

Yup, SMW is right, trapped air. Cooling systems in these things stink, thermostat mounted too low, they are notorious for trapping air in the system when refilling. I always drill the thermostats just as SMW showed, but with only 1 hole on each side.

**impalaws6** · 04-29-2015, 03:40 PM

I think I fixed it! I lifted the hell out of the front end. Bled the system by the TB, squeezed both upper/lower hoses like crazy. Turned on the car with rad cap off. I could hear air moving. I added coolant as needed, squeezed the hoses again. Once in a while I would pull off the hose by the TB. Reved the engine couple of times. It now shoots hot air and the needle barely made it to 210 mark after being on for 10 minutes. DO you guys think its fixed?

**impalaws6** · 04-29-2015, 03:42 PM

The only thing I am concern is that the lower hose is warm, not hot like upper but just warm, is this ok?

***SMWS6TA*** · 04-29-2015, 04:46 PM

yes....that IIRC cool side going in.

And I should have said just one hole

**JayTA98** · 04-30-2015, 05:19 AM

Sounds like you figure it out, great job. For future reference anytime you drain the radiator or system get in the habit of either removing the TB hose like you did or the front coolant bypass hose. With the car off, start to slowly refill the radiator and keep an eye on the disconnected hose. When you see coolant coming out of the tube/hose then you are good. Put the hose back and top off the radiator. Take the car for a short ride and once it is cold again check the level as it could drop a little more. Top it off again. Check the coolant level in the morning for the next couple of days until the level doesn't drop.