unidentified leak

[orbitalannie]

I recently had my first overheating incident here in Melbourne...and after much advice seeking from online communities I successfully fixed the faulty pipe with a piece of hose, and bled the cooling system...but just 2 weeks later, I am gutted to discover a new leak.

The real problem is in identifying where it is. A consistent drip drip at the centre of the undercarriage 'tray' was my first clue. Removed the tray and found a small puddle of water at the front centre of the engine. My neighbour tells me this is afore the 'sump'...on the top edge of the housing and in front of a number of belts...? His guess was it may be coming above - from the water pump but was confused by a lack of hose to the area in question.Other than the puddle there is precious little evidence of the leak.

Has anyone got any bright ideas?

Also I have recently been told that as my model is a conversion (something to do with the heater being different?), I need to bleed the coolant by running the engine hot and letting air out of the rad cap, with the aid of a large towel...rather than by the funnel+bleed pipe method I read about online. Again - any thoughts?

It goes without saying any advice is much appreciated.

[wonkanoby]

could well be your water pump

[wonkanoby]

second bit reads like rubbish to me

evan if rear heater was removed bleeds the same

[Northern Bongolow]

the heater will be the same in the front, but the rear may have been bypassed or removed, look for 2 RUBBER pipes entering the floor from outside just to the rear of the drivers door(under the floor) so from a bleeding point of view its still the same.
there are3 videos on youtube,(how to bleed a mazda bongo) by b*witched blingo, these ma help.

when checking the waterpump for leaks there are 2 telltale holes that the coolant can leak out of on the casting.
one is visible from the passy side(slightly hidden by the belts). the other is a the 6 oclock position and is nearly impossible to see without a dentists mirror, as this is the lowest hole it usually leaks here undetected.
if the waterpump is age unknown i would change it anyway.

[Simon Jones]

Maybe the 'conversion' is a Ford Ranger head which does not normally have a bleed pipe fitted. I'd suggest locate the bleed pipe first & treat it a a standard Bongo bleeding process.

[Northern Bongolow]

good one simon, on rereading the original post again i think you are onto it. he could fit a bleed pipe into the turbo supply pipe,done this with good success on a few.
dont like the idea of bleeding through the cap much.