Bongo Fury

hi ...wonder if anyone can help ..ive had issues in the past with my 2.5 m reg bongo over heating mainly due to me stupidity of forgetting to replace header tank cap ..also had to repair a couple of hoses due to wear n tear! so bleeding has kinda become second nature when things go wrong !

today however ive had a different problem, the temperature shot up and as i tried to remove header cap the water (much cooler then usual) came spilling from the overflow pipe ! ..the radiator had water so i waited for it to cool and topped up the header tank with view to bleed it ..road side! ..no air bubbles ! and i managed to limp home with no more overheating!

a couple of things ive noticed recently, no 'blow' from the air conditioning ..when i last bled the system the bottom hose didnt get hot!...it has not been losing water since last hose repair (last Thursday, after which i drove 800+ miles) and everything been running fine till today ! ..in the past the pressure has been high along with boiling water flying out ( that was 4000+ mile ago tho) although today the water was tepid but engine seat are was noticeably hot !

if anyone could shed some light id be grateful as now waiting for the rac to come have a look!!

Welcome! There may be a few things to tease apart in what you've told us, but most pressing are probably today's issues. I would advise not to drive it again until you get it sorted. Watch what you let the RAC guy do as well... don't just let him start it up and rag it until he sees coolant...

Sounds like you have or have had a major airlock, most commonly settling in either the cylinder head or the front heater matrix. When bleeding, you HAVE to get the bottom hose hot.

Good luck. More advice should be forthcoming...

this bottom hose is it on drivers side or passenger ?? ..bottom drivers is hot ..passenger is cold

what if the bottom hose stays cold ?? ...the rac guy just told me if the bottom hose goes hot ..ive got a problem, we just ran it to temp and no overheating, now bleeding system, all my back heater are blowing hot air ..front heaters not blowing at all ! ..rac man 'sniff tested' and liquid stayed blue, rather than turned green!

he possibly thinks its the thermostat not opening n advised to have new one fitted but as he couldn't get the thermostat to open he just left me with his number in case i have trouble tomorrow !

barrythebeepbongo wrote:this bottom hose is it on drivers side or passenger ?? ..bottom drivers is hot ..passenger is cold

what if the bottom hose stays cold ?? ...the rac guy just told me if the bottom hose goes hot ..ive got a problem, we just ran it to temp and no overheating, now bleeding system, all my back heater are blowing hot air ..front heaters not blowing at all ! ..rac man 'sniff tested' and liquid stayed blue, rather than turned green!

he possibly thinks its the thermostat not opening n advised to have new one fitted but as he couldn't get the thermostat to open he just left me with his number in case i have trouble tomorrow !

The hose on the passengers side from the head dissappears downwards towards the front. This is the main outflow from the head and should get hot. Under the front at the passengers side are two rubber sections joined by a steel pipe, and are the return from the radiator to the thermostat. The 'stat should start to open around 82degC and be fully open by the time the radiator fans kick in at 91-92degC (in my van).

If the bottom hose gets hot then the system is doing what it should - it is not an indication of a problem in itself.

You say the front heaters are not blowing at all - do you mean by this that the front heater fan is not turning on? Could be a fuse, or crud build up in the fan housing. An air lock in the front heater or something else preventing coolant flow would cause the fans to blow cold, but they should still blow. Pressing the aircon button when the front fans are blowing should additionally cause the radiator fans to start.

If you're familiar with bleeding the Bongo (please tell us your method), then replacing the 'stat should be easy enough to do. An incomplete description of the job can be found here... http://mazdabongo.wikispaces.com/Servic ... thermostat. The BongoFury shop should stock them, as well as various other places.

Do a search too on the temperature gauge - the standard Mazda temperature gauge is useless. There are a few options to modify or supplement the gauge.

If the bottom hose stays cold while bleeding then you're not bringing the radiator fully into the circuit and you could be left with air in the system, despite having bled.

Having a negative sniff test result is a good sign, but you need to get the thing properly up to temp and bled.

Fingers crossed, but still don't drive yet...

Driver+Passengers wrote:The hose on the passengers side from the head dissappears downwards towards the front

The first sentence should have read "The hose on the driver's side from the head dissappears downwards towards the front.".

Sorry.