Technical Coolant Loss

[cgarr04]

Hello...

My car appears to be loosing coolant quite rapidly after topping up with some (2yr/red) antifreeze. I added it on sunday with probably 400mls of oil as it was too low for comfort. I then drove a few miles to the garage, got another litre of oil and put well over half of it bringing it to almost max. I then drove ~60miles or so before parking the car up.

I drove the car to work today and came back to find a parking ticket which was absolutely my fault and stupidity for completely forgetting that i parked it in the city centre and not my friends driveway!

And to top it off i've come home to check mine and a friends car only to find that the coolant is almost at the MIN line again. So once again i've topped it up to max. There are no obvious leaks or funny stuff on the oil cap and the car is running fine, there is also no overheating and the radiator fan is going fine albeit needing replaced.

The car has never had an issue with overheating or losing coolant. The only thing I can think of that may relate to this problem is that the rocker cover seal needs replaced as it's leaking a little oil over the engine.

Is it possible that the coolant has unearthed some gunk and exposed a leak? I'm hoping it's not the headgasket?

 

[s and b]

can you get a small independant garage or radiator specialist to do a pressure test on your cooling system as it might just be a fissure somewhere
ask how much, most would do it for free if they have the time

 

[fingers99]

Bleed the cooling system and wwatch again. You will find significant differences between hot and cold (antifreeze expands as it gets hot) plus there's a limited "self Bleeding" effect as any little bubbles of water get pushed round the rad.

Often the only way you can see a leak from the water pump or the water rail seal is by running the engine up to temperature and peering under the car with the offside wheel off.

Pressure test will show up the leak and a HG fault where combustion gasses are entering the coolant.

 

[DaveMcT]

Radiator leaks tend to dripp from the bottom of the front bumper.

Water pump and coolant rail tend to leak from the bottom of the cam belt cover.

However this does not explain the oil loss. A head gasket failure will not show any visible coolant leak and can sometimes cause oil to leak into cylinder 2 or 3.

The problem needs to be properly investigated. Continue driving, and it could get extremely costly.

 

[s and b]

fiat punto radiators seem to fail halfway down n/s where they go into the end cap,cant explain why might be due to them flexing as they only have one upper mount

 

[DaveMcT]

The rad support bar also corrodes badly further affecting support.

 

[cgarr04]

Hi guys,

Thanks for the comments thus far.

There was no sudden loss of oil, the oil was just on the min mark and i checked it prior to making a long journey (smart move), so i topped up at home with the remainder (400mls approx) of the 5litre container I had. Then i drove a few miles to the garage, got a litre and put most of that in. This was only a few days ago as stated above and the oil is generally still at the same level. The car has always been a little heavy on oil, which I have generally blamed on the rocker cover gasket. It's used approx 7 litres over 5months/7000miles (since i've had the car).

I phoned a mechanic nearby my place of work and the car is booked in for 9:00am tomorrow for a compression test. Although, this may not happen so soon as the guy couldn't provide me with an cost estimate over the phone as the 'boss' wasn't there. (I don't trust this nature of approach to begin with...). I've used this garage before and they charged me £65 for an brake pad, oil and oil filter change (I supplied the parts, but not the oil), with no 'vat' receipt, otherwise he wanted extra money to make up for the VAT. Does this sound reasonable or is he pulling a fast one to make a few pounds? He told me he was trying to do it as cheap as possible for me...

Anyway, I checked the car this morning and coolant was still at max, so off I went to work at 8am in it and done a 10mile round trip to and from work with 90% of the journey on the motorway at high speed. I came out of work and before starting I checked the coolant, which only appears to have dropped slightly and there was absolutely no leaks on the ground nearby. Got home and left the car ticking over for 20 mins whilst eating, came out, revved it alot, checked around the engine and under car for leaks - nothing. Knocked the car off, released the coolant cap slowly, lots of gas was released and the coolant had risen slightly above max, but not up to the narrow "nozzle" point. There doesn't appear to be any oil in the coolant and no coolant in the oil either. The exhaust produces absolutely no smoke of any colour regardless if started cold or warm and there is plently of airflow, although there does seem to be a minor influx of air at times, like the exhaust is 'spitting' - although it's only really noticable if you put your ear near to rear bumper or hand your hand a few inches from the exhaust. I will also mention again that the car runs absolutely fine, no overheating issues at all (ever), the rad fan runs okay, too.

A week or so ago my girlfriend heard the car produce a strange hum like noise when de-accelerating and it appeared in-sync with the engine and but i dropped the clutch and gear, give it some ummphh in 4th, up into 5th again and it was gone...strange - could this be related?

Would it be fair to say that this just appears to be a small leak somewhere when the car is at high temps and rapid loss of coolant only occurs when the pressure is at peak levels , thus it leaks?

The last thing I want is to go to this garage tomorrow for him to see the an in-experienced guy with 'R' plates, assume I know absolutely nothing and tell me the head gasket is gone and hit me with a figure of half the price of the car...

Colum

 

[fingers99]

You can buy compression testers for 15 quid posted on eBay -- they're not the nicest to use, but will do the job. And a compression tester is one of the best diagnostic tools out there. If you can remove spark plugs and fill a teaspoon with engine oil, you, too, can do a compression test.

To do a dry and wet compression test takes about half an hour. So, unless you live in (and maybe play for) Chelsea, 25 quid is plenty.

Get them to write down the results, post them here before you take any further action.

BUT, a compression test won't tell you where the leak, if any, is. For that (and to test for compression gas to coolant) you need a coolant pressurisation test. Fewer garages have the kit, but it's what I'd recommend in this situation.