General Cold Air after Coolant flush! - Help?

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General Cold Air after Coolant flush! - Help?

Bolinhas899sx

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So I'm changing the Radiator, Thermostat, water pump and hoses (radiator top and bottom and few other), but before changing all of this i wanted to make a super flush on my Cinquecento 899c 98 sx. (cause was full with sludge - previous owner run it on tap water for 2 years and now is all calcified and rusty)

So after almost two full afternoons I've done the following:

. Swapped the water tank (cause the old one was fuulll with sludge).
. 2x cycles of distilled water.
. Back flushed the engine from the top and from the bottom of the Thermostat entry and water pump hose.
. Back flushed the radiator from the bottom and top.
. Back flushed the heater exchanger as well from the inlet and outlet.

. So much dirt and rusty bits came out and now only Cristal clean water comes out from it.

. Now I've mounted everything as it was, and poured distilled water with a Wynn's Radiator flush cleaner. I'm letting it run and sit for a few days (before fitting the new parts) - (there is a small leak from the Thermostat entry - normal as the old gasket is gone) + plus the old Thermostat is gone.. Is stuck open! I've tested myself with boiling and cold water and either way it just allows watter out)

I've bleed out through the small pipe near the lamp until water comes out.

But now when I put the heater on full blow with the switch to hot.. No heat comes out!! Only semi cold air comes out! Do you guy's think I've blown my heater!? Any tips? Flush it again? Air on system?

Do you guys think i should replace the parts and hope the heater will start working or just order a new heater? And if so could anyone tell me how to access my heater?

Thanks again everyone. I really appreciate it.
 
Last edited:
Air.. almost certainly :eek:

My technique :

Open the bleed screw a little squeeze a hose ..as the water seeps through bleed screw.. close it

Then fill coolant to within 1cm of the filler neck

Start and run engine

Level will Rise with HEAT..

BUT..

Drop with Purging of trapped air

Feel the hose from thermostat to radiator..

It should be cool for a few minutes then get HOT quickly..as the thermost opens

Once it has opened..
You can switch off engine

Once cold.. check the levels ;)
 
Last edited:
Air.. almost certainly :eek:

My technique :

Open the bleed screw a little squeeze a hose ..as the water seeps through bleed screw.. close it

Then fill coolant to within 1cm of the filler neck

Start and run engine

Level will Rise with HEAT..

BUT..

Drop with Purging of trapped air

Feel the hose from thermostat to radiator..

It should be cool for a few minutes then get HOT quickly..as the thermost opens

Once it has opened..
You can switch off engine

Once cold.. check the levels ;)

Problem is my Thermostat is stuck open, so the hoose, well all the hoses are hot.

Guess i will change all the parts and then fill with distilled water and then try this.

As you are saying inded the water rises above the max level.. But then it drops.. I assume it was do to the fact the Thermostat as no gasket and it leaks a bit from there..

Thank you very much aresecrazy!?
 
heater set to hot is critical here, if its not then not water goes through the heater box at all, it controls water flow through the heater matrix to change the temp, not change the air route around it.

I think it might be the cinq 899 that doesnt have a bleeder for the heater matrix, i dont think anyone has mentioned one yet, but it obviously helps if its there lol. With the heater bleeder i normally dont even run the car to bleed it, they bleed that easy normally.

The bleeder by the headlight is just for the radiator, the rest needs to work itself out, the stat shouldnt matter at all so long as you got the heater set to full it should flow and bleed up.. But it will take an absolute age to warm up. I personally wouldnt worry about the bleeding right now, get the new stat on and everything buttoned up and then when you come to bleeding it properly the last time it will warm up really quick and make sure heater is set to full hot, fans dont matter leave them off so it heats up quicker. Once you think its bled, cap back on expansion tank and let it cool right down completely, top up as required before you restart from cold, and on that cold start listen for any telltale gurgles
 
heater set to hot is critical here, if its not then not water goes through the heater box at all, it controls water flow through the heater matrix to change the temp, not change the air route around it.
The Cinq doesn’t have a valve on the heater.
Coolant flows through it all the time, no matter what temperature the heater is set to.
Heater temperature adjustment is by air flaps.
 
Air.. almost certainly :eek:

My technique :

Open the bleed screw a little squeeze a hose ..as the water seeps through bleed screw.. close it

Then fill coolant to within 1cm of the filler neck

Start and run engine

Level will Rise with HEAT..

BUT..

Drop with Purging of trapped air

Feel the hose from thermostat to radiator..

It should be cool for a few minutes then get HOT quickly..as the thermost opens

Once it has opened..
You can switch off engine

Once cold.. check the levels ;)

Thank you all again!

I've tried varesecrazy method and it worked within minutes of squeezing the bottom radiator hose.

Hot and cold air again!! ?

You guys are life and money savers!! ?

Thank god I've joined this forum.. You guys are legends! ?
 
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I also leave here a diagram of the coolant circulation on the Cinquecento 899 sx (1998).

It helped me understand the flow in order to do the super flush, and it might help others who need some guidance as well.

Thank you all ?
 

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