Confused re thermostat replacement in NC

Technical Area Engine, Transmission, Exhaust etc
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  1. My model of MX-5 is: __nc
  2. I’m based near: ireland
  3. I’m looking for technical help or recommendations on: __thermostat
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oops , should have completed my question ?
I notice that in winter months the car never gets up to temp on the gauge, so im guessing the thermostat is faulty. in fact the car has the auto 6 speed box and in the cooler days it struggles to change into 6th , Im assuming the gearbox must be linked to engine temp somehow ??
Anyway, It looks like I need the longer 100 mm thermostat based on my early vin number. What im confused about are 2 things that maybe another forum member can shed some light on .
1 Why are nearly all the listings including the housing ? Is it necessary to replace th housing / thermostat as one piece ?
2 There is a HUGE variation in price , from 20 quid for a make called Napa to 40 ish for a Borg and Warner to nearly 80 quid at the MX5 parts site. I would not be tempted by the 20 quid, but would think the B and W one must be good .All. comments advice more that gratefully accepted
Thank you
willie

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Buy the one in the link below. They all come complete as a unit with gasket, unbolt the old fit new.
Some earlier NC’s had a shorter neck stat fitted on the engine, a longer neck stat (most I’ve seen are those anyway) will fit those if you trim the hose by 30mm to get a snug fit.
Mx5parts sell both stats short/long neck (higher price, genuine Mazda) the one linked below will do the job though…

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Thank you. much appreciated

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IMG_9132
IMG_91323264×2448 1.34 MB

IMG_9139
IMG_91393264×2448 1.94 MB

IMG_9134
IMG_91343264×2448 1.52 MB

IMG_9135
IMG_91353264×2448 1.54 MB

This is the ‘stat I fitted :white_check_mark::+1:t3:

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I read somewhere that a 2 litre Mondeo thermostat fits perfectly if you trim the pipe to match the thermostat you remove.

I bought a Mondeo thermostat a few years ago, but didn’t get round to fitting it and I’ve had no temperature issues.

Does anyone know if the Mondeo thermostat does indeed fit?

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that’s super thanks , ill go look at mine in the AM

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I’m unsure about that and which Mondeo TBH. Mahle show a very similar stat in appearance but different cat no, and operating temp to the Mazda one, 90° the Mazda is 82° I believe. That’s comparing a 2 litre petrol up to 2014. Apart from that my limit knowledge on Mondeo’s tells me just use one suitable for the Mazda.

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Video on changing it:
Mazda MX5/Miata NC Mk3 - Maintenance Episode 13 - Thermostat & Coolant Change - YouTube

The Thermostat I used:
Coolant Thermostat fits MAZDA MX5 Mk3 2.0 05 to 14 NAPA CJ5E8575AA LF5015170 New | eBay

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Just want to say thank you to all, I ordered the stat as advised here, fitted it and all good. many thanks

willie

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