Technical Gurgling from heater matrix

[Raino144]

Dear all,

I’ve had my 2016 Panda for about 4 months now. 48,000 miles only, only done 3,000 last 4 years in total.

Had a major service done at MOT time in August + water pump and belts replacement. Following this gurgling from behind the passenger side dash.

I’ve bled the cooling system and the problem goes away for a few days, but then rapidly returns. Supposedly the garage had pressure tested the cooling system as OK.

Heater works fine, no water ingress into the cabin, temps all show as normal.

Any pointers for the next cause of issue? Head gasket?

 

[jackwhoo]

Which procedure used to bleed cooling system?
Do you regularly need to top up coolant?

 

[jackwhoo]

Have you checked the plastic stub on thermostat housing for leaks?

 

[Mike1alike]

Any pointers for the next cause of issue? Head gasket?

Hold your horses! First thing, as jack mentioned, is coolant level dropping?

 

[Raino144]

Which procedure used to bleed cooling system?
Do you regularly need to top up coolant?

Fiat service manual - run car at idle with cap off cooling system for 23 mins, topping up as necessary, then opening heater pipe bleed valve, revving to 2000 with coolant being topped up into the tank to keep above Max, until procedure completed - thermostat opened and cooking fans definitely kicked in. Had to do this twice in last 2 weeks.

No other noticeable coolant consumption other than bleed procedure

 

[Raino144]

Have you checked the plastic stub on thermostat housing for leaks?

None noticed here either

 

[jackwhoo]

Is coolant tank a header tank ie highest point in cooling system, or expantion tank on side of radiator

 

[Raino144]

Which engine ? Which fuel?

1.2 8v 69bhp, petrol

 

[Zardo]

Fiat service manual - run car at idle with cap off cooling system for 23 mins, topping up as necessary, then opening heater pipe bleed valve, revving to 2000 with coolant being topped up into the tank to keep above Max, until procedure completed - thermostat opened and cooking fans definitely kicked in. Had to do this twice in last 2 weeks.

No other noticeable coolant consumption other than bleed procedure

There're actually two bleeding points, not one, right? Did you only bleed the heater pipe?

Slowly introduce the coolant into the reservoir taking care not to exceed the MAX reference mark.

2. Tighten the bleed fitting on the radiator as soon as coolant emerges from the threaded hole on the bleed fitting.

3. Continue the refilling operation and tighten the bleed on the pipe to the heater as soon as engine coolant fluid comes out.

End the operation of the refilling the engine coolant as soon as the MAX level is reached.

4. Close the expansion tank cap.

Start up the engine and let it idle for at least 2 minutes.

Carry out periodic and gradual acceleration until the engine speed is around 3000 rpm. This operation should be carried out until the engine cooling fan cuts in at least three times.

Stop the engine and wait until the coolant has cooled down.

Check that the level of the engine coolant is between the MIN and MAX marks on the expansion tank.

 

[jackwhoo]

0010T20 ENGINE COOLANT - CHANGE - Fiat - NUOVA 500 - eLearn - 4CarData

 

[Raino144]

I’ll have another go with these instructions- slightly different to the manual I have which only shows to do the radiator bleed valve on refilling (not bleeding) the system. Will report back!

 

[Zardo]

I’ll have another go with these instructions- slightly different to the manual I have which only shows to do the radiator bleed valve on refilling (not bleeding) the system. Will report back!

maybe the system was incorrectly bled after replacing/refitting the water pump, and therefore there was a lot of air inside

procedure

 

[Raino144]

maybe the system was incorrectly bled after replacing/refitting the water pump, and therefore there was a lot of air inside

procedure

This is also my suspicion.
But my concern is that after bleeding the system and driving 20-30 miles there’s another pocket of air released
Trying the bleed procedure above: fingers crossed.

 

[Raino144]

2 more bleed attempts done -
There was air coming out of the radiator valve on both bleeds. After the first bleed still a lot of swishing; after 2nd somewhat better but not 100%.

Last time running the engine and then the heater pipe bleed valve seemed to purge the air but contradictory to the above!!!

Maybe if this doesn’t work then to follow the full coolant drain and refill instructions (i.e. starting from scratch) might be the next step?

Thank you all for your help so far, headscratcher this one!

 

[jackwhoo]

2 more bleed attempts done -
There was air coming out of the radiator valve on both bleeds. After the first bleed still a lot of swishing; after 2nd somewhat better but not 100%.

Last time running the engine and then the heater pipe bleed valve seemed to purge the air but contradictory to the above!!!

Maybe if this doesn’t work then to follow the full coolant drain and refill instructions (i.e. starting from scratch) might be the next step?

Thank you all for your help so far, headscratcher this one!

no need to drain and start again as you will just introduce air into system

 

[Raino144]

There may have been some mild frustration as I had to enlist my wife to put her finger on the heater bleed valve as I searched for the screw with a torch… after it had made a bid for freedom under the car… efforts will continue in daylight!

 

[jackwhoo]

if you follow the fiat instructions correctly then stop .....any small amount of remaining air will work its way into the expansion tank.

 

[Mike1alike]

The best way to bleed the system is to do it with the engine turned off.
Get the filling cap down and fill up. Open the radiator breather. When coolant comes out, tighten the breather. If coolant doesn't come out, put more coolant in until it comes out to the opened breather. Then move to the second breather and do the same. If after doing the bleeding the coolant is above 'Max' level, get some coolant out using a hose or some sort, to make the level between Min - Max. Put the filling cap on and that's it!

 

[Raino144]

Just reporting back… the Panda gave a few ‘glubs’ on warmup this morning and then settled down. 10 mile motorway loop done without any further noise, temps normal and heater etc working all OK. Letting it all cool down, will recheck expansion tank level but fingers crossed it’s got the job done