fiesta zetec - coolant loss

gyppo

Hi All,

Belated happy xmas to all btw.

Missus Gyppo's fiesta seems to be consuming coolant at a slow, but nonetheless worrying rate. About every month, it needs about a pint of coolant to be added.

First thought to me is the HG is in the early stages of decline, however there are none of the classic symptoms - oil is clean, coolant is clean with no sign of pressurizing, no sludge under the filler cap, and no steam from the exhaust.
Engine runs perfectly, temp guage remains in the same spot once warmed up. No sign of any obvious leak anywhere either.
Anyone any pointers???...

DublinDilbert

gyppo wrote: »

Hi All,

Belated happy xmas to all btw.

Missus Gyppo's fiesta seems to be consuming coolant at a slow, but nonetheless worrying rate. About every month, it needs about a pint of coolant to be added.

First thought to me is the HG is in the early stages of decline, however there are none of the classic symptoms - oil is clean, coolant is clean with no sign of pressurizing, no sludge under the filler cap, and no steam from the exhaust.
Engine runs perfectly, temp guage remains in the same spot once warmed up. No sign of any obvious leak anywhere either.
Anyone any pointers???...

Does sound like a coolant leak..... get your hands on a pressure tester and pressurise the system... you should be able to find the leak fairly quickly with that on.

Avns1s

I'd be looking for leakage at the water pump or less likely, some leakage at the joints in one of the hoses. With that minimal amount of coolant loss, it won't show up easily as the coolant will evaporate as quickly as it gets out.

I would have thought that if it was the Head Gasket, that it's breakdown wouldn't take that long, in other words, by month 2, you'd be putting much more than a pint of coolant in or you'd have contaminated oil or other sign.

Check the hose joints carefully, then the water pump.

What year is the car and mileage BTW?

crosstownk

DublinDilbert wrote: »

Does sound like a coolant leak..... get your hands on a pressure tester and pressurise the system... you should be able to find the leak fairly quickly with that on.

Agreed - having a pressure test should find the leak, especially if the test is done while the engine is cold. When the engine is hot it could be venting as steam as pointed out by Avns1s....

Avns1s wrote: »

With that minimal amount of coolant loss, it won't show up easily as the coolant will evaporate as quickly as it gets out.

Darragh29

There's a coolant/heater flow control valve on that make & model that is known for causing jip. It's kind of near the bottom of the windscreen as you are looking at the car, it's below the right hand windscreem wiper as you are looking at the car with the bonnet open. I'm looking for a pic here on Google images of the component or where it is located but can't find a pic of the component... If you are handy and can root around for it, it has I think either 2,3 or possibly 4 small flexihoses going into and out of it with a solenoid to control flow. I changed a few of them and you'd have it changed in ten minutes if you can find it and it is leaking...

Darragh29

crosstownk wrote: »

Agreed - having a pressure test should find the leak, especially if the test is done while the engine is cold. When the engine is hot it could be venting as steam as pointed out by Avns1s....

I wouldn't be throwing money into a pressure tester 'cos they aren't cheap, the system is pressurised anyway when it is hot so I'd just run the engine to get it warm and put an hour into looking for a leak.

Darragh29

OP, have a look at the attached pic, the red circle shows the area where this component is located and as best as I can recall, the red arrow points more or less exactly where this device is. You'll have to take off the plastic grid I think to get to it which might also require taking off the wipers, which is handy enough with a 13 spanner. I think you can bend up that plastic cover a bit or in any event you can see through it with a torch to see if there is a leak down there...

gyppo

Hi All,

Many thanks to all of you for the advice on this. The car is a '99, and has 67k miles on it.

I'd agree that a HG failure would have manifested itself over this time scale, and a leak somewhere is the most likely cause.

Darragh, many thanks for the info. Do you know if this valve is located in roughly the same place on a 99 model - the pic you attached looks like the 02 onwards model. I'll delve further in this area.

crosstownk

Darragh29 wrote: »

I wouldn't be throwing money into a pressure tester 'cos they aren't cheap, the system is pressurised anyway when it is hot so I'd just run the engine to get it warm and put an hour into looking for a leak.

But if it's a slow leak that's venting as steam it may be impossible to find while the engine is hot.

I'm not suggesting that the OP buys a pressure tester - I'm suggesting that he/she gets it pressure tested while cold - an hours labour perhaps.....?

DublinDilbert

crosstownk wrote: »

But if it's a slow leak that's venting as steam it may be impossible to find while the engine is hot.

I'm not suggesting that the OP buys a pressure tester - I'm suggesting that he/she gets it pressure tested while cold - an hours labour perhaps.....?

Yea me either... Obviously what darragh said is good as a first pass, check when the engine is warm for any leaks. A pint / month is going to be a very small leak...

If he could get the correct pressure cap adapter for his car, he could even use a cheap foot pump with a gauge on it.

Also if he can't find a leak he should get the pressure cap itself checked out, as a small amount of the time these can open too early and vent some steam. Some times if this is happening you can see a build up of white/blue material around the pressure cap from the venting...