My car seems to be losing coolant, from max to min in a few weeks.

It has started doing this since i changed the thermostat and a small hose with a bleed screw that went into the heater matrix.

Only thing is, after i did these repairs, when i filled up the coolant, nothing came out of any of the two bleed screws (maybe i poured it in too fast?) Anyway, not suprisingly over the first week or so after i had done this the water level kept going down and i topped it up, not suprisingly as i assumed as water is being pumped around, air locks would be removed. However, it has been several weeks now and it still keeps losing coolant.

I changed the head gasket about 4 months ago and am getting no steam, mayo or misfiring, and when i start the engine i cant see any visible leaks ( i especially checked the parts i recently changed and the front of the hg)

The only thing is i seem to have some kind of gunk collecting on the top of my airbox (!?) and i have some crystal deposits around the filler cap. When i switch off the engine i can hear air hissing out of the cap.

Would it be possible to loose this amount of coolant through the filler cap? (have just got a new one but cant put it on yet as engine is still warm)

Do you think i should drain my coolant again and bleed it properly?

Thanks

Phil

Hi,
You need to make sure the heaters are on the hot setting and with the engine running slowly undo the bleed screw until water or air comes out......when all the air has finished coming out and water starts coming out then your system is bled..

Thanks
Paul T

Thanks Paul

Will try that now

Phil

Have done as you said, quite a few air bubbles came out.

Ran it for quite a while and took it round the block a few times, then looked hard for leaks, can see a little bit around the hose to the bottom of the radiator, maybe i didn't tie the jubilee clip up enough.

When i switched it off there was no hissing through the new cap. Lets hope it holds on to coolant for a bit longer now.

Is missfiring a little again at low revs, and at idle, but hopefully its something less sinister than head gasket this time. I can't see any of the other "classic" signs. I think i will get some decent HT leads when i get my new student loan next week, as it has recently had new plugs.

Phil

Hi,
I had a problem with the fan switch leaking on my 899cc cinq, the copper washer was leaking and it sits just above the bottom hose to rad connection and drips water on to the jubilee clip of the bottom hose........something else to check when your looking for leaks..

Thanks
Paul T

Does your electric fan turn on?

Mine didn't and as it got hot, pressure built up in the coolant system and water came out of the expansion tank... oops

New fan switch didnt fix it so bypassed the switch and put an on/off switch on the dash... BODGE! lol

It now doesnt leak, but the expansion tank hisses when you switch off the engine...

the heater control valve or cock was leaking on my sei, that was an intermittant leak, if the heater was on hot it would leak, it the heater was on cold it wouldnt, it took me weeks to figure out what as wrong and £!50 to fix it

Yeah, my fan turns on fine at about 90 ish

The new cap has stopped it hissing now, i suppose i just have to wait now and see if the level goes down again over the next few weeks, if it does then i'll have to start head scratching again...

Phil

gaz_wrexham said:

the heater control valve or cock was leaking on my sei, that was an intermittant leak, if the heater was on hot it would leak, it the heater was on cold it wouldnt, it took me weeks to figure out what as wrong and £!50 to fix it

Click to expand...

ooohhh....where is this valve located?

behind the battery and all the furry stuff on the sei, am not sure if its the same position on the cinq, i would imagine it would be though

the part is a selector for either hot or cold water to be selected and the water loss is minimal, but over a few days it gets noticable

Thanks Gaz, i will definitely have a look at that because i moved all of that out of the way to replace a pipe to the heater matrix, and thats when the problem started!

might have disturbed summat