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Mysterious Coolant Loss... Part Deux,

Ok so not brilliant news ..

It lost coolant driving back from were you bought it ( private sale ? ) and it over pressurises when run upto temp.

The temp .. 100 is too high for a car at idle so you have a fan issue or you have a coolant circulation problem .. there is one other but ill leave that till the end.

Lets say there is an airlock .. coolant wont circulate and it will over heat .. that will push coolant out the cap .

A faulty water pump or thermostate will do the same .

A faulty cap .. basically not holding pressure will do the same .

The last one .. which you dont want to hear is a headgasket failure and having x2 headgaskets it might be tricky to find which one .

I will say its very rare , in fact i havent seen one go this way .. when they normally go it lets coolant into the engine and you get D chunk ... again ive only ever seen a handfull in nearly 15 years .

First thing is replace the cap .. and get the system bled out.

Then get your garage to do a "sniff test " .. its a device that detects combustion gasses in the coolant ... if this is ok then thermostate / water pump is were i would be looking next and im kinda leaning towards these due to the temp the car got to ..

Btw .. 100 is not an over heat .. 120 is ! .. 100 is also the boiling point of non pressurised water !!!


Sorry for the bad news but i always try and list out what a fault can be .
 
Actually not really bad news at all DM as I've fairly well convinced myself it's an engine failure :grin:
Anything less than that is a bonus.
The coolant has been flushed. The garage used a vacuum system tho they did NOT do the 4K revs to run any last air out. This needs to be done.
The thermo has just been replaced with a low temp item and the garage confirm that there was a temp drop when the thermo opened.
There's a replacement cap on the way from FrazerPart (04 part number)
The other thing that needs to be confirmed is whether there's a blockage at the rads. The garage have IR equipment to check these. They say they'll also check the coolant for CO2.

By the way the engine runs really smoothly, so unless it's very early D chunk I'm hoping it's the other minor problems.

As always, it's most kind of you to spend time advising.
Will update when I hear word.
Thanks!
 
You either have D chunk or you dont .. its a big bit of the cylinder wall missing basically .. and a wrecked engine so its not that .

Its also not an engine failure .. i NEW you would be thinking that .. im happy to give you my number and we can chat on the phone if you want .

3K revs is all thats needed .. engine will be cold at that point so thats plenty .

Rad blockage .. new one on me if so .

Water pump .. the impellar can wear or indeed break off .. this WILL cause the issues you have .

I would still lean towards this as it fits the symptoms .

If you want to go the worst possible way atm then headgasket but if it is this and a sniff test will soon confirm then its a new one on me !
 
Thanks again , most helpful and dare I say it upbeat!
It even be worth just sticking a new water pump in anyway as I've no record of one being changed til now (tho records aren't complete)

I'm going to start with asking them to bleed if they haven't done so, stick the new cap on and work from there.

Monday can't come quick enough,
 
A quick update all,
I received the updated coolant cap this morning, the old one WAS faulty and not pressurising the coolant. Which was hiding the real problem, a slight leak at the base of the expansion tank.
So, tank and water pump (while in there) on order, and hopefully I'll finally be on the road!
Huge thanks to DeMort in my hour of need, who correctly guessed the way things were going to go!
 
:eek:

... agreed!!
 
Sorry to hear it is the tank and not the radiators. I hope you were sitting down when you checked the price. I'll be interested to sew the state of the water pump when it comes off.

MC
 
Will let you know MC.
The coolant tank is one of those jobs that everyone dreads. I'm just getting it over and done with early ...
Re pump, it SEEMS to be running ok, but it's just future proofing the car seeing as the coolant system is being sorted. I wouldn't be surprised if the impellers are worn to nothing tho!

By the way, she's running a whole lot cooler even with that mild leak.
It's amazing the difference a clean around the rads makes.
 
Ok that was my other worry .. the car shouldn,t get to 100 at idle . 80 on the gauge is the norm and i lean towards water pump impellar in these situations as the first port of call .. plastic .. sigh .

If clearing the rads has lowered the temp then that issue is sorted without the need to change the water pump.
 
Good points DM, it's on order so I'll go get it in, and be happy it's another item crossed off the list.

Theoretically I THINK what was happening was .. stuck in traffic, the coolant cap wasn't air tight so the polling point was lowered, air bubbles were created, along with crud encrusted rads, the car heated up more than normal, which then opened up the very slight crack at the base of the header tank. From there it was going to have to blow out someplace, and I was suddenly more than 2L down.

Now however, with the new cap and crud cleared the temp never goes above the 12 O'clock mark , the coolant doesn't boil, the header tank crack stayed closed, and little or no coolant is lost!

It's very difficult to figure when in the middle of it all tho..
 
if its fixed .. then its fixed :D

I dont normally recomend replaceing something thats not broken , but in this case ill make an exception .. i would like to see the water pump replaced which you are already doing just to be on the safe side .

if it sits at 80 on idle then the cap was the problem .. they never get much above this and ive run up a few of them in my time :)
 
Not so mysterious this time!
Took her out a few days ago for a 'warm up" down our local country roads. When I parked up I spotted that my car is now taking to 'cocking the leg"..
Leak coming from the area of the offside rad this time.
Thankfully D911 were quick off the mark and have sent me a spare.
Back to bleeding and checking levels again
:roll:

The joys of bringing an occasional car up to every day driving status.

Hopefully she'll remain coolant tight for a while once this is done.

There a lot to be said for air cooled!
 

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