am i missing something??? where did it go???

the hat · February 11, 2010, 01:42:41 PM

i would get some dye and a spare rad cap drill a hole in the top of the rad cap and the base of the sprung seal fit a tyre vale in the top of the cap and pump some pressure in or dont be cheap and buy a pressure tester lol if you have a leak it will show as a pressure drop and nothing will be too hot to touch etc and the dye should show you where it is

monterx7 · February 14, 2010, 01:16:44 AM

i havent got the colored dye yet but i did pick up a compression tester. did acouple tests to try and figure out where this coolant is going, but came up STILL with nothing.

first off, the coolant level is raising in the overflow bottle. just not sure if its from when i slowly release pressure with the rad cap. and it is a new rad cap.

second, i pulled off the rad cap and pulled the egi fuse for this next test. had the wife turn the key while i watched the coolant at the rad. after acouple of seconds i saw what seemed to be consistant air bubbles. so that got me thinking....

next, i pulled leading plugs so i could see what would come out. turned the key, compressions sound good and nothing out of the rear rotor. front sound good, but had what i think was fuel mist coming out. that leading plug was wet when i pulled it and the wife said it smelt like fule. so maybe a leaky injector on the front (great another issue).

next, installed comp tester (regular piston tester) into each rotor housing with the check valve pushed in. turned the key with the rad cap on and off. if i had a blown water seal should there be a difference with and without cap? well i thought so. but no difference on the front and rear rotor.

after messing around with different combos of this sort, i re-installed both plugs left the rad cap off then turned the key. strange thing, no air bubbles......

Prof · February 14, 2010, 08:18:00 AM

I\'m just in the process of rebuilding my engine because a water seal let go.

I did the compression test same as you\'ve done - and got no obvious sign I had an issue either. I was thinking about how that would be and the only conclusion I can come up with is that the compression test only gives a pressure reading without combustion - so it\'s about checking seals - at 7 BAR or there abouts - it\'s possible for the water seal to still hold against the water pressure, but with much higher combustion pressures it will give and you see the evidence of this as bubbles in the coolant.

The problem is that bubbles in the coolant can just be air that\'s got into the system from a slow leak, and then is being pushed around to the radiator by the water pump once the engine is run.

There is a chemical test for combustion products in the coolant - it may be worth trying that - at least you\'d know one way or the other.

Having said all of the above - you have several of the symptoms:

Coolant being pushed into expansion bottle
Bubbles in the radiator when engine running
Coolant level drop

But of course there are possible explanations for all of those that don\'t involve coolant seal failure.

m1tch · February 14, 2010, 09:39:26 AM

I had my coolent buzzer go off as there was a leak in the pipe going from the block to the heater matrix (down next to the plugs below where the oil filter is) it was just a small leak, but was enough to leak when the engine was on lol

monterx7 · February 14, 2010, 10:33:15 AM

Quote from: Prof;672253There is a chemical test for combustion products in the coolant - it may be worth trying that - at least you\'d know one way or the other.

i was looking into this. just not sure where to buy from

cyman · February 14, 2010, 12:35:43 PM

the first thing you need to do is fill the system completly and bleed it so youhave no air in it. trying to do tests when you know there maybe air in the heater matrix or in the system from the leaks before will not help you.

you need to start from a clean sheet of paper so to speak. put the heater to hot open any in line bleed valves if you have them and get the system properly full. once youve run it up and the engine is hot with the thermostat open (test this by seeing if the top and bottom hosses are bloody hot on the rad not just the top one) turn the engine off lett the pressure drop then check your levels one last time top them up as needed then go through all your checks. run the engine up so its to the stage where its at high temps and the system is pressurised then start checking your pipes,rad for weeping,heat from the heater,if you find nothing take it for a 10 minute run then come back let the pressure drop and check your levels. if you try any of the above before you have bleed the system and sorted the levels all you will get is the existing air in the system causing you issues.

monterx7 · February 15, 2010, 12:53:14 AM

im thinking i found it!

before getting the car into the garage last night i made sure the floor was nice and dry. when i went out today to start tearing it apart i looked under and found ALOT of coolant. i pulled the air pump and parts before starting anything. naturally i looked in the engine bay above the coolant on the floor. the lower rad hose was wet near the rad. kept looking up noticed a trail of coolant under the lower rad hose up to the return line from the turbo, up the water pump housing then finally up to the thermo housing. i THINK its from there. strange thing is ive looked around the lower hose area when all this first started, and everything was dry. or this could just be new problem.

so hopefully tomorrow i can find a gasket, if not then a tube of rtv.

TiddlesRX7 · February 15, 2010, 08:53:02 PM

Fingers crossed for you bud. Maybe the leak has got worse so you didn\'t notice it first time round.

monterx7 · February 15, 2010, 09:19:42 PM

i pulled the thermo housing today and guess what? the o ring was not in correctly. does anyone know where i can buy just the o ring?

Prof · February 16, 2010, 07:06:57 AM

I got mine from Rotechniks - but it\'s a standard Mazda part - Thermostat gasket or something it\'s called.

grinder · February 16, 2010, 09:41:14 AM

when i wanted one for the rad filler neck - i took it to a local plumbing place who had a box full of washers - spent about 15 mins finding one that matched and handed over the 27p for it ( or some silly amount like that )

monterx7 · February 16, 2010, 11:10:00 AM

i did something to that effect with the same part grinder. but the thermo seal/gasket is round yes, but the seal/gasket itself has a square shape to it. wonder what a normal o-ring would do in its place.

Prof · February 16, 2010, 11:18:59 AM

should use the proper part for this one - thermostat won\'t seat properly otherwise

grinder · February 16, 2010, 01:03:49 PM

ahhhhhhhhhh didnt realise it was square

i think its a

N3C1-15-173 @ Â£2.00 ex vat - BUT thats a old price list ( and i think it could be an old part number aswell )

monterx7 · February 22, 2010, 10:58:49 AM

i did a search and i dont think there is a mazda dealer near me.

since i didnt have a new gasket i decided to try and reuse the old one. i know i know, bad idea. while im waitn for my mazdatrix order to come in i figured ill give it a go. just like you would expect, it didnt work. so for now the car sits in the garage until i get my parts.

i think the closest mazda dealer is in cambridge. or does someone know of any other one near swaffham