Coolent loss, engine overheating-dead bongo or just sick?

[patjunfa]

Hi all

Our bongo has overheated a number of times in the last couple of weeks and loses it's coolent..ive read the other threAds here relating to this and it seems to be a commen enough problem..

1st time we were driving in France and the rubber pipe from rad towards engine burst a little hole..a garage there cut the pipe a bit shorter. Did they bleed the system and ensure no airlocks?

We brought it to our own mechanic who changed the thermostat, and bled it to ensure no airlocks..but found that the coolent system was still pressurising so said he reckoned the engine must have cracked..he then took out the radiator to check it and thought it wasn't too bad..since then it's driven a few times around 12 miles without overheating, but still losing it's water.. 
Does this suggest perhAps he cleared a block in the radiator and this has stopes the overheating? Im hoping the fact it can drive this far without overheating suggests that the cylinder header isnt cracked..is this so?

What are the checks that need to be done? What I think I pick up from previous threads are
Check no airlocks in coolent system..are pipes on top of rad hot while bottom cold
Check water pump-been told that if internal heater works as it does then there is probably no problem with the above two..
Possibility of Micro holes that lose mist from system that aren't visible as holes..how do you check this? Somewhere said about a uv dye and using a uv light.

Possibly the engine is cracked and this is pressurising the coolent system 

We replaced the engine about 4 years ago and costing e2500-3000 it'd probably not be worth doing again.  It's a lot of labour taking the whole engine out and pressure testing it, I'd rather not waste money on this if I'm going to have to buy a new van/car after. At the same time how can I drive it til it melts or give up in it without knowing..


Any suggestions much appreciated
 
Patrick 

[haydn callow]

I would say it has not been bled properly when in the garages and the result is a "blown" head......the fact it will do short journeys is not unusual. ....... just needs the head replacing..... the rest of the engin will probably be o.k. your problem is....finding a garage over there that knows how to do the job...

Losing coolant without a leak strongly points to a "cracked" head

[patjunfa]

Tnks for reply.
If it is the head, does the whole engine need taking out and checking? Or how would you know that the cylinder is not also cracked? If it is only the head, where would I look for this and how much roughly would you expect to pay for the job?


Thanks

Patrick

[patjunfa]

The other question I suppose is, if I get engine going again how to ensure same doesn't happen again..
Mechanic said rad pipe may have gone from pressure in overheated/cracked engine..said the design of bongo having engine under seat means it can run into overheating problems easily..
A coolent alarm would be a good idea.
I love my bongo but don't want to keep pumping money into it if it's life is limited..

[Northern Bongolow]

look on youtube for bleeding a mazda bongo, there are 3 video's. if you get the bongo to bleed up as in these you may be ok. i would suggest you do a pressure test on the system first, as you cannot bleed it properly if you have a leak.
good luck.

[wonkanoby]

i would replace the chopped hose first

[patjunfa]

Thanks for that
Started watching YouTube vids..interesting..will try..hope bongo survives and allows me to become more informed on it's maintenance.,