losing water i think!
Discussion
Ok looked into the radiator after noticing that the expansion bottle was empty
and you could not see any water, so i filled it up using a antifreeze mix also filled the expansion bottle to max line
went out a drive came back and it had pissed it all back into the expansion bottle it was now full and overflowing
when it had cooled down a bit i slowly opened the radiator cap lots of air came out then i removed it after the pressure was gone to find
you could not see any water in the radiator but as said the expansion tank was full
the temperature gauge is sitting at normal, if i don't fill it back up it still runs ok but after a day or two you don't get hot air from the heaters
and have to fill it again
the oil is nice and clear no mayonnaise, and i cant find any leeks, just the water from the expansion tank overflow
any help apreseated.
and you could not see any water, so i filled it up using a antifreeze mix also filled the expansion bottle to max line
went out a drive came back and it had pissed it all back into the expansion bottle it was now full and overflowing
when it had cooled down a bit i slowly opened the radiator cap lots of air came out then i removed it after the pressure was gone to find
you could not see any water in the radiator but as said the expansion tank was full
the temperature gauge is sitting at normal, if i don't fill it back up it still runs ok but after a day or two you don't get hot air from the heaters
and have to fill it again
the oil is nice and clear no mayonnaise, and i cant find any leeks, just the water from the expansion tank overflow
any help apreseated.
I sympathise, I have this on mine. As said before do radcap and stat first, and give the radiator a good flush with a hose. Also check the cooling fan works and comes on at correct temps. If it continues, sadly it is likely to be headgasket failure causing high pressure regardless of the lack of usual symptoms. Mine passed sniffer tests, no mayo, no water in oil etc.
Hopefully yours fixes easily, I'm getting the engine swopped in the spring as some ex-owner spannermonkey bodged the wrong head on mine, hence the seal leakage and over pressurising.
Hopefully yours fixes easily, I'm getting the engine swopped in the spring as some ex-owner spannermonkey bodged the wrong head on mine, hence the seal leakage and over pressurising.
Looks like it could be the thermostat ...
put the front of the car up had the expansion tank to min, started car, let it run
pressed the hoses, then after the car heated up started to eject water from the radiator
also the fan did not come on , as it did not reach temperature, just sat below half
so my guess the thermostat
What is yours... ???
put the front of the car up had the expansion tank to min, started car, let it run
pressed the hoses, then after the car heated up started to eject water from the radiator
also the fan did not come on , as it did not reach temperature, just sat below half
so my guess the thermostat
What is yours... ???
If it was just thermostat...
Stuck open: car just doesn't warm up. Heater stays cold.
Stuck closed: car overheats. Heater works very well. Rad stays cold.
Sounds more like rad cap to me but it's good practise to replace both together and you might as well flush the cooling system (block as well as rad) while you are at it.
Stuck open: car just doesn't warm up. Heater stays cold.
Stuck closed: car overheats. Heater works very well. Rad stays cold.
Sounds more like rad cap to me but it's good practise to replace both together and you might as well flush the cooling system (block as well as rad) while you are at it.
stevie_a said:
Looks like it could be the thermostat ...
put the front of the car up had the expansion tank to min, started car, let it run
pressed the hoses, then after the car heated up started to eject water from the radiator
also the fan did not come on , as it did not reach temperature, just sat below half
so my guess the thermostat
What is yours... ???
The thermostat is very simple to remove and check. Make sure you have a spare thermostat housing gasket though for refitting.put the front of the car up had the expansion tank to min, started car, let it run
pressed the hoses, then after the car heated up started to eject water from the radiator
also the fan did not come on , as it did not reach temperature, just sat below half
so my guess the thermostat
What is yours... ???
I've spent hours researching this from the issues with my car and sadly 9/10 times high cooling system pressures (ie water forced out the radiator when upto temperature) after stat/cap change and rad flush is head gasket. It doesn't have to go in a big way, my car sounds sweet as a nut, drives well, yet clearly something is leaking into the water and causing excess pressure and in turn water forced out the overflow.
Are you getting:
a) lots moisture out the exhaust pipe and/ or some white smoke.
b) high dipstick oil levels
c) bubbling noises from expansion tank after turning engine off after a drive
These are my only symptoms of HG failure, has passed several sniffer tests etc.
I would get a new Mazda rad cap first. Then remove thermostat and whilst removed flush the block through with a hose and also flush the radiator thoroughly. Check the thermostat opens correctly (dunk it in a saucepan and heat to just below boiling). If you're lucky a new rad could solve it,if you're not (like me) it's new HG time.
Edited by vrsmxtb on Tuesday 22 November 18:23
thanks for replies vrsmxtb
this thread made me think as I have just replaced the cam sensor o ring
and the car ran ok before and I know the idle is lower than before I fitted it
so might turn it a bit to increase until i can get a strobe onto it
this thread made me think as I have just replaced the cam sensor o ring
and the car ran ok before and I know the idle is lower than before I fitted it
so might turn it a bit to increase until i can get a strobe onto it
MozzaMX5 said:
One other think you could check is the ignition timing, if it is retarded it can cause the engine to overheat.
Mozza
your last post was Saturday 10th September what stage are you at now?Mozza
Edited by stevie_a on Tuesday 22 November 20:31
Well, I was prepared to have the HG done this year when it was discovered a previous owner bodged a Mazda 323 head on the car. Weighing everything up (cost of new head plus fitting on top of gasket change, uncertainty about condition/history of rest of engine etc) I have basically run out of money for the car for this year.It is currently SORNed and in the Spring I am just getting the whole engine changed, which will be £850 all in done professionally by an MX5 specialist.
I really did think long and hard about the car but decided to keep investing, as it is a very tidy car otherwise. Mine is a pretty extreme case though, at worst I'd imagine your problems are gunged up rad or HG.
I haven't touched the timing on mine by the way so no idea how much effect it has on overheating issues.
Keep reporting back mate, I'd be interested how you get on
I really did think long and hard about the car but decided to keep investing, as it is a very tidy car otherwise. Mine is a pretty extreme case though, at worst I'd imagine your problems are gunged up rad or HG.
I haven't touched the timing on mine by the way so no idea how much effect it has on overheating issues.
Keep reporting back mate, I'd be interested how you get on
Edited by vrsmxtb on Tuesday 22 November 21:13
vrsmxtb> Is that including a known good engine? Seems a good price, given that you are North Kent that has to be Mark at Freelance!
I had the same symptoms as you - bubbling expansion tank, losing coolant through overflow, no obvious leaks. Stat & cap were changed, rad flushed several times. A new radiator fixed it, so if yours looks original buy the MX5parts one and swap it in as it might sort it and is a lot cheaper than a head gasket! The car will thank you for it anyway!
I had the same symptoms as you - bubbling expansion tank, losing coolant through overflow, no obvious leaks. Stat & cap were changed, rad flushed several times. A new radiator fixed it, so if yours looks original buy the MX5parts one and swap it in as it might sort it and is a lot cheaper than a head gasket! The car will thank you for it anyway!
NiceCupOfTea said:
vrsmxtb> Is that including a known good engine? Seems a good price, given that you are North Kent that has to be Mark at Freelance!
I had the same symptoms as you - bubbling expansion tank, losing coolant through overflow, no obvious leaks. Stat & cap were changed, rad flushed several times. A new radiator fixed it, so if yours looks original buy the MX5parts one and swap it in as it might sort it and is a lot cheaper than a head gasket! The car will thank you for it anyway!
Mark has worked on my car, but found a more competitive price for the change over the river in Essex. That is a known good, decent mileage engine I'm told.I had the same symptoms as you - bubbling expansion tank, losing coolant through overflow, no obvious leaks. Stat & cap were changed, rad flushed several times. A new radiator fixed it, so if yours looks original buy the MX5parts one and swap it in as it might sort it and is a lot cheaper than a head gasket! The car will thank you for it anyway!
I just got a new cap from Mazda this morning and on the way home had to pull in as the gauge started to go up past half way
all the coolant had pored back into the expansion tank
So not the cap then
will get the timing done next, then i am going to take the thermostat out to see how it runs
before replacing
If it is not them will price on getting the head gasket done
any idea how much to expect replacement head gasket to be done in a garage
all the coolant had pored back into the expansion tank
So not the cap then
will get the timing done next, then i am going to take the thermostat out to see how it runs
before replacing
If it is not them will price on getting the head gasket done
any idea how much to expect replacement head gasket to be done in a garage
If I remember correctly head gasket change was roughly £300 at an indie, and you may as well change the cambelt unless it's been done recently as it has to come off anyway.
Before thinking about HG I would still flush the radiator and block just in case there's any blockages. Any ideas why the previous owner had a new radiator? He may have been having problems already? I suspect mine was moved on for similar reasons.
Before thinking about HG I would still flush the radiator and block just in case there's any blockages. Any ideas why the previous owner had a new radiator? He may have been having problems already? I suspect mine was moved on for similar reasons.
Took out the thermostat today
first thing I did with it was put it in a bowl and put boiling water in it ( and it did not open )
so put it back together without it and I have ordered a new one which will arrive Wednesday
so will see how it runs going to work this week
but cross fingers it is the thermostat.
first thing I did with it was put it in a bowl and put boiling water in it ( and it did not open )
so put it back together without it and I have ordered a new one which will arrive Wednesday
so will see how it runs going to work this week
but cross fingers it is the thermostat.
A contractor has been working in my work for a few weeks now
I had been talking to him, turns out he is right into cars
I was telling him about my water system fault.
He came in today with a kit to test for head gasket failure
first he put it on and pumped it up and everything looked OK
then he put on another part with a blue dye in one side
started the engine,it immediately turned yellow indicating head gasket failure.
Time to start getting prices.
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