Thermostat changed.

[daveblueozzie]

Just changed the thermostat, replaced with a genuine Mazda thermostat.
Used Forte Coolant Flush, then flushed with clean water, took a few hoses off including the rear matrix and flushed the radiator.
I have taken a few pics of the thermostat that was taken out, in a way I'm a bit disappointed, it still looks brand new even after a year, probably didn't need to change it.
Water pump change tomorrow.

Flushing the radiator till it runs clean.



Genuine Mazda stat on the right of the picture.


Even inside the stat housing looks exceptionally clean.

[mikeonb4c]

Dave - you're getting obsessive. get out and get a life (Hmmmm - ought to practice what I preach )

[mikexgough]

Great pics Dave..... looks like your right with your 'Stat....didn't need changing but there you go....BDC has another brand of Thermostat to try ....I have a Tama brand in mine (they make 'em for Mazda,Subaru, Ralliart, Nissan etc) and I get midway 50% 12 oclock on the Mason during normal running and up a little under load.... rarely runs the fans unless at very extreme conditions, the system seems to have been designed this way.

Look forward to more pics of the water pump change...

[daveblueozzie]

Changed the water pump today (as well as an oil and filter change and fuel filter )
As with the stat the pump looks perfect inside.
A few pics .
New pump on the left old one on the right


Does not seem to be much, if any weepage from the holes in the housing. The red on the pump is coolant, found a hose not quite tight, so found my slow leak with any luck.

[mikexgough]

Good work David....... as can be seen from your photos, if you have a coolant leak ....the Red Coolant has a dye in it as seen on your water pump exterior.. ....good also to see that your 'stat and pumps are "as new" when removed, whether down to the excellent Forte flush, the Car Plan Red or a combination of both.... .... I shan't ask how the bleed went as your well rehearsed at that..

[mikeonb4c]

Interesting design change in number of blades new pump vs. old pump - I wonder why they did that?

[mikexgough]

Interesting design change in number of blades new pump vs. old pump - I wonder why they did that?

Most of the pumps now are made in China and are 8 blade.... you can still get the 6 blades at 3 times the price of the Chinese made ones...... the Japs and Russians use the 8 blades with no difference to cooling effect or system pressure....

[daveblueozzie]

Good work David....... as can be seen from your photos, if you have a coolant leak ....the Red Coolant has a dye in it as seen on your water pump exterior.. ....good also to see that your 'stat and pumps are "as new" when removed, whether down to the excellent Forte flush, the Car Plan Red or a combination of both.... .... I shan't ask how the bleed went as your well rehearsed at that..

I don't think the Forte Flush in the system for the 30 minutes that your supposed to leave it in, would clean it that much , but i could be wrong.
The Car Plan Red Coolant is deffo the best stuff to use , have used it for the last four years.
As for the bleed, the way me and BDC do the bleed, works for us , OK it might not be the way most do it ,but it works.

[widdowson2008]

Interesting design change in number of blades new pump vs. old pump - I wonder why they did that?

Cost Mike. Take a closer look at the two pumps. Blade profile on original is curved and probably a more efficient shape (more expensive to manufacture).
From the 3rd pic, you can see a trail from the hole, suggesting it probably was leaking a little. Just my opinion of course.

Excellent pics Dave

[daveblueozzie]

Interesting design change in number of blades new pump vs. old pump - I wonder why they did that?

Cost Mike. Take a closer look at the two pumps. Blade profile on original is curved and probably a more efficient shape (more expensive to manufacture).
From the 3rd pic, you can see a trail from the hole, suggesting it probably was leaking a little. Just my opinion of course.

Excellent pics Dave

If it had have been leaking wouldn't it have been stained red, the hose that wasn't quite tight leaked onto the casing, and as you see stains the casing, no staining from the hole.

[widdowson2008]

Interesting design change in number of blades new pump vs. old pump - I wonder why they did that?

Cost Mike. Take a closer look at the two pumps. Blade profile on original is curved and probably a more efficient shape (more expensive to manufacture).
From the 3rd pic, you can see a trail from the hole, suggesting it probably was leaking a little. Just my opinion of course.

Excellent pics Dave

If it had have been leaking wouldn't it have been stained red, the hose that wasn't quite tight leaked onto the casing, and as you see stains the casing, no staining from the hole.

Stained red? Don't know, but if the coolant stained owt it made contact with, why is the inside of the pump not stained?
Also, if that trail from the hole isn't a coolant leak, then what is it? Definitely a trail of something.

[bigdaddycain]

Interesting design change in number of blades new pump vs. old pump - I wonder why they did that?

Cost Mike. Take a closer look at the two pumps. Blade profile on original is curved and probably a more efficient shape (more expensive to manufacture).
From the 3rd pic, you can see a trail from the hole, suggesting it probably was leaking a little. Just my opinion of course.

Excellent pics Dave

The pump seems to be of decent quality Steve. and certainly seems to be a viable option from a new mazda pump seeing as it weighs in at less than £40. I hope it is ok, i've got one for my own bongo!

There was no descernable difference when it came to bleeding really... The only concern was how long it took to get the new mazda stat to open.

We got a LOT of air out of the system, maybe because the rear matrix had been disconnected and flushed out. Dave's bongo is like mine on the bleeding front, i.e. not a pig to bleed! Though as mentioned erlier, she took a while this time round i suspect because of two things.... Rear matrix emptied and flushed, and waking up the new stat.

We let the bongo self bleed with a spot of decanting to help her along a bit.

I'm just on my way to Dave's now to replace the ATF fluid/clean the magnet/new gasket etc... I anticipate having to top up the coolant when i check now she's cooled overnight and the remains of any trapped air has vented off into atmosphere. She should be good to go then!

What did you think of the stat pictures Steve? I promise i didn't clean up the old stat!

[bigdaddycain]

Excellent pics Dave

If it had have been leaking wouldn't it have been stained red, the hose that wasn't quite tight leaked onto the casing, and as you see stains the casing, no staining from the hole.[/quote]
Stained red? Don't know, but if the coolant stained owt it made contact with, why is the inside of the pump not stained?
Also, if that trail from the hole isn't a coolant leak, then what is it? Definitely a trail of something. [/quote]

I think Dave was saying the staining was from a leaking hose above Steve. There seemed to be no staining immediately below the pump housing. I wasn't around when Dave nipped up the loose hose, so i cant really comment... I'm sure Dave will elaborate when he see's this.

P.s.... All the core plugs i could see looked new Steve Still a shiny alloy look to them, i had grubby hands yesterday so i'll take some pics later before i manky my mitts up

[widdowson2008]

The pump seems to be of decent quality Steve. and certainly seems to be a viable option from a new mazda pump seeing as it weighs in at less than £40. I hope it is ok, i've got one for my own bongo!

What did you think of the stat pictures Steve? I promise i didn't clean up the old stat!

Lot to reply to here ste, and I can, and will, only speak from what I have seen.
First off lets clear up something about 'pattern' parts. For a company to manufacture and sell an alternative to the original, they need to match the original specification laid down by the original manufacturer, but to make it commercially viable, they need to make it cheaper.
A good example is Sainsburys Home Brand foods. Heinze tomato ketchup and Kellogs Cornflakes spring to mind. Sainsburys stuff LOOKS the same, and are packaged almost identically, BUT there is a difference to the taste - that 'secret' ingredient missing. They they both do the same job, but one is cheaper.

In the cases of thermostat and pump, I believe a similar thing applies.
The pump has a different design of impellor blade (cheaper to produce) but probably not quite as efficient a design, hence the need for two more blades to achieve the specified flow rate. (just a guess).
The thermostat is similar. The internal working parts seem to be identical, but the Mazda stat has that extra seal on the stem. Again, cheaper to produce, but it meets the same performance specification.
In both cases, the ony factor that remains unknown is the service life.

As far as the stat pictures are concerned, I have a few thoughts (being the proud owner of about 20 donated stats for testing).
First observation is that visually, they fall into two categories. They are either VERY clean, or they have some sort of brownish coating.
Suggestions have been made that the brown coating is caused by the antifreeze. The clean ones (and this appears to apply to the pipework as well) all seem to have used the red antifreeze, but not in all cases. So....., is the brown stain caused by the antifreeze? or could it be the result of oxidisation (rust particles from the steel pipework?). Also considered whether the brown coloured ones have been subjected to an 'overheat' situation.

So much stuff to learn...........


Query on the hole in the pump that 'appears' to be leaking.
Why can't it be plugged? say by drilling, tapping, and fitting a washered set screw. What is that hole actually for? Anybody know?

[mikeonb4c]

I suspected cost was the reason

As ever, I'm 'circumspect' over what effect it may have on pump performance and - more significantly - on longevity. On the plus side, it seems to me that if the appropriate monitoring devices are installed, the driver will be alerted to signs that pump performance is slipping, or a leak developing).

But it is interesting to consider what complications may arise throughout and economy from cheaper components being put to use as critical parts in - well - any setup really. Mazda thermostats anyone?