Technical water temperature while sitting in traffic

Currently reading:
Technical water temperature while sitting in traffic

In my case the car will overheat in traffic initially. But when bad it will start overheating while driving as well especially if car is pushed harder. Overheating I believe is caused by the exhaust gases entering the coolant system. Initially causes air to enter the radiator which makes the radiator ineffective causing overheating, and when it gets worse it affects the coolant flow by blocking it all together. When this symptoms happened to me I replaced the head gasket within a 1 week or so.
 
Describe how you bleed the system. I think you are doing it wrong.
 
im following mk1, mk2 guides

fill tank to top, open one bleed screw, wait till you get clear flow of antifreeze, close bleed screw open other one and repeat, after that fill it so level is between min and max run till fan turns on

bleed it few times on my other cars and never had this min to max bug occur
 
car is warmed up
top of rad is also hot
coolant level doesnt drop to low fast but slowly as the car warms up, on the other hand when i turn car off and by the time i walk outside to check coolant level it is already at max

-----------------engine ON --------------------------- engine OFF
 

Attachments

  • DSC03487.JPG
    DSC03487.JPG
    692.7 KB · Views: 21
  • DSC03486.JPG
    DSC03486.JPG
    622.5 KB · Views: 16
Open all bleed screws. (Sorry I don't remember where mk1 has it's bleed points)

Keep filling until coolant drips out of one bleed screw.

You close this bleed screw and continue to fill coolant until it's full or the heater bleed screw starts dripping.

At this point every bleed screw must be closed.

Start the engine and wait till the radiator fan opens two times so you are sure the thermostat is open and coolant flows.

Crucial part from my experience:

Rev the engine around 3000rpm for some secs and let it idle again. Repeat a lot of times.

Check coolant level and fill to max if necessary.

If you rev the engine and coolant goes to min from max then you have air in the system. Usually on this car air is trapped in heater radiator so you may have to bleed again through its' bleed valve. Check if heater works.

If you don't have stable idle at startup or there's white smoke (a lot) you have a blown head gasket.

My previous car was a GT mk1 that used to do that btw, engine off - coolant to max, engine on coolant tank empty. But I had idle problems on startups and a lot of white smoke from the exhaust. One day temp went to red limits and that's it. Engine bye bye :/

So the smartest way if the method I suggested don't work is to make a compression test or at least look at your spark plugs.
 
Last edited:
Nice pictures, but I can't figure out what parts of punto mk1 they represent. Is this a oil system or coolant system mayo?
 
last pic is air filter plastic housing, other pictures are a pipe that attaches to cam cover and goes inside air filter box
-----------------------------------------

final conclusion

temperature was so high when driving slowly in traffic cuz fan wasnt turning on at correct temp, changing radiator temp sensor fixed it, fan turns on when temp gauge goes over middle mark

as for coolant fluctuating from max to min, reason for that was air inside cooling system, bleeding it again fixed it

-----------------------------------------
 
OK the mayo may be normal so not indicating any head gasket issue.

However, replacing the temperature switch may not solve the issue. Once the radiator traps air and needs bleeding the temperature switch stops working properly as the water in the radiator does not heat up sufficiently as a mass and the switch is not activated. It happened to me too when the head gasket went and air was getting trapped in the radiator. The switch was not faulty and could still use it.

Hopefully this is not the problem in your case though.
 
OK the mayo may be normal so not indicating any head gasket issue.

However, replacing the temperature switch may not solve the issue. Once the radiator traps air and needs bleeding the temperature switch stops working properly as the water in the radiator does not heat up sufficiently as a mass and the switch is not activated. It happened to me too when the head gasket went and air was getting trapped in the radiator. The switch was not faulty and could still use it.

Hopefully this is not the problem in your case though.

mhm
 
The link between mayo and HG issues becomes more tenuous the further you get from the sump. Short trips increase the chance of mayo even in a healthy engine as one of the by products of combustion itself is water (which is why you see water coming from exhaust pipes on cold engines, even on cars without a cat).
 
The link between mayo and HG issues becomes more tenuous the further you get from the sump. Short trips increase the chance of mayo even in a healthy engine as one of the by products of combustion itself is water (which is why you see water coming from exhaust pipes on cold engines, even on cars without a cat).

what do you consider short trips i make 10km one way trip every day
 
Back
Top