The Profiteer

I emailed BHR and they said they are none left with them nor any affiliated vendors.

There also a bit out of my price range as BHR Ignition Coils were next on the list before this coolant issue arose.

I'm left with a choice of Koyo, Mishimoto and Megan Racing and I'm in the process of deciding.

1) Koyo seem to be the cheapest, but their A/T specific model seems to be a replica of the factory, so same plastic housing and single core element. Also I've heard mixed reviews regarding fitment issues.

2) Mishimoto make a decent aluminium 2x core option, it's the priciest of the 3, but they do also sell their universal transmission cooler which will make it compatible with an A/T model.

3) Megan Racing make a near identical model as Mishimoto from what I've seen and is priced a little better, trouble is it's M/T only and idk if the hardware exists to make it A/T compatible?

Decisions, decisions...

I was looking at replacing the cooling fan shroud as well, but was wondering if it would make any determinable difference over the stock and if the $180 couldn't be put towards something that'll make more of a noticeable difference.

Regarding the coolant reservoir, if it is indeed the float that's causing the coolant light malfunction, would I be correct in assuming that the original sensor should still be fine and thus not need replacing with the tank.

MazMart, are the replacement coolant reservoirs you have the latest revisions for the 1st gen model, as I know Mazda overhauled the tank and made many subsequent modifications in an attempt to resolve this issue.

Thanks MazMart and NYCGPS for the imput.

nycgps

iTrader: (1)

1. Koyo makes 2 models , 1 is OE-like replacement, like u said, it's just like OE. the other is their Racing line of radiators, but only available for MT

2. MT only, mixed reviews

3. same as #2

Don't get any aftermarket fan shroud , waste of money

Mazda changed the float material, but as far as I know it still suffers from the same kind of problem, just the matter of time. if you are handy with small wire cutters, u can get bottle only, cut the old sensor out and install it to the Tank only version. saves u a a lot of money.

dannobre

iTrader: (3)

I believe that the OEM ones are made by Koyo...so they are likely the same...

You can likely install a MT radiator of your choice and an AT oil cooler...might be a simple compromise

nycgps

iTrader: (1)

oem is made by Calsonic.

most people who op for aftermarket way went the MT rad + AT oil cooler route, it blocks a bit of air flow but it's not that bad.

I have that setup in my overseas 8 (came with it), but the aftermarket rad's quality is so bad so it went straight to garbage. got BHR's "last" AT rad but i have yet to install it (engine is dead, no time to rebuild)

just yeah make sure you get some quality Radiator.

Mazmart

iTrader: (12)

Yes, the ones we sell are the latest ones from Mazda. You can buy the cheapest one from us with no sensor and install your original sensor.

Regarding the radiators, Calsonic makes the OE. The factory style Koyos that we sell are VERY similar. I would suggest using all of the foam from your old unit if you install a Koyo. Fitment is perfect but the foam is there for a reason.

I have sold the Mishimoto once and the customer was kind enough to report that it did have fitment issues but I told him of that possibility in advance.

Paul.

40w8

1. You should read my thread about putting a 18,500BTU derailer tube radiator in line with atf radiator where rock grill is located. On cool days like 60 degs under cruise the engine runs around 178-182 (so cold thermostat barely opens). The trans and engine each run around 193 deg on hot day cruise.

2. I have scanguage pluged into code reading port, and found atf code from Mazda 3 so I can read trans fluid and water coolant.

3. Put in Mobil 1 0w40 which is very good, cheap, and easy to find. It's the same thickness as 10w30 @32 deg, but doesn't thin out as much at operating temp, so run it year round.

I bet nobody can get engine temp down this good with any radiator on a manual trans car. If you have auto it's easy and cheap.

RIWWP

iTrader: (2)

That's a pretty tall bet there.

At 109,000 miles on my 8 (MT), I replaced the radiator (Koyo from Mazmart), coolant bottle, radiator lines, and installed a 172F thermostat. Even up to 95F, my cruising temps were sitting at 172F. My temps just sitting still would oscilate betweeen 172F and 185F, where the fans would kick on. In the winter in sub zero temps, I would often dip down to 168F in cruise.

Brand new parts counts for more than strategy. Strategy counts for plenty if you are still heat soaking your system, but new parts can still provide more than enough cooling for street conditions.

40w8

Ok you win.

I'm not one to fight the engineering of a car.

I just look for easy tweaks.