1.1 radiator cap on expansion tank is in good condition according to the mechanics? Maybe I will replace it anyway just so I know for sure.
Cheers
Alvin
Mechanics have run out of ideas on how to fix cooling system
Moderators: Doone, westonwarrior
Re: Mechanics have run out of ideas on how to fix cooling sy
Can't hurt.
Have the garage done a 'Sniffer Test' to check for combustion gasses in the coolant?
Have the garage done a 'Sniffer Test' to check for combustion gasses in the coolant?
Re: Mechanics have run out of ideas on how to fix cooling sy
Hi there,
I owned a Bongo auto free top 2.5 td for 6 years in NZ, from 80,000km, to 190,000km.
unfortunately, your first mistake is trusting a garage to know how to empty, refill and bleed the bongo system, which is a 18 step process that takes me 2 hours, plus cool down period, then top up again. For peace of mind, this is something you should do yourself, or if you let the garage do it, then double check that the system is air free by going through the bleeding process yourself. If the system has already been refilled, it only takes half the time, as there is less burping required.
It is unlikely that any garage is going to wait around this long, and most use various methods to refill, with mixed results. Some well equipped Garages have power pressure filling equipment. I suggest you follow the Mazda recommended method of bleeding the system, If you still have problems, you know its due to a cracked cylinder head.
You are right to be checking the bottom hose behind the bumper, it can take up to 1/2 hour of driving @ 50km/h dependent on aimbient air temp, before the bottom pipe gets warm (ie the thermostat opens and flows water). At 100km/h, the thermostat will probably not open, the bottom pipe will be cold, and a few minutes of idling will be needed for it to open again, hence yoou can probably drive long distances fine.
*After the thermostat was replaced on mine, I noticed the fans would kick in much earlier than before.
As posted by someone else, turning on the AC turns on the radiator fans, so if you are worried about it the state of the thermostat, that will reduce the max temp.. maybe by 20 degrees!
Replacing the thermostat and waterpump is easy for the garage to do at the same time as replacing the cambelt (to save labour), they are all hidden away under there.
If you do not know the service history, replacing the water pump, thermostat and flushing the system should fix the problem if you haven't done damage already driving it around.
I owned a Bongo auto free top 2.5 td for 6 years in NZ, from 80,000km, to 190,000km.
unfortunately, your first mistake is trusting a garage to know how to empty, refill and bleed the bongo system, which is a 18 step process that takes me 2 hours, plus cool down period, then top up again. For peace of mind, this is something you should do yourself, or if you let the garage do it, then double check that the system is air free by going through the bleeding process yourself. If the system has already been refilled, it only takes half the time, as there is less burping required.
It is unlikely that any garage is going to wait around this long, and most use various methods to refill, with mixed results. Some well equipped Garages have power pressure filling equipment. I suggest you follow the Mazda recommended method of bleeding the system, If you still have problems, you know its due to a cracked cylinder head.
You are right to be checking the bottom hose behind the bumper, it can take up to 1/2 hour of driving @ 50km/h dependent on aimbient air temp, before the bottom pipe gets warm (ie the thermostat opens and flows water). At 100km/h, the thermostat will probably not open, the bottom pipe will be cold, and a few minutes of idling will be needed for it to open again, hence yoou can probably drive long distances fine.
*After the thermostat was replaced on mine, I noticed the fans would kick in much earlier than before.
As posted by someone else, turning on the AC turns on the radiator fans, so if you are worried about it the state of the thermostat, that will reduce the max temp.. maybe by 20 degrees!
Replacing the thermostat and waterpump is easy for the garage to do at the same time as replacing the cambelt (to save labour), they are all hidden away under there.
If you do not know the service history, replacing the water pump, thermostat and flushing the system should fix the problem if you haven't done damage already driving it around.
