NC Aluminum Coolant Expansion Tank for MX5
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Images may differ from actual product appearance.

NC Aluminum Coolant Expansion Tank


PART NUMBER: 61-2037


Reg. Price: $270.00

Sale Price: $213.00




Free shipping offers apply only to destinations within US Lower 48.

Reg. Price: $270.00

Sale Price: $213.00




Free shipping offers apply only to destinations within US Lower 48.


Direct replacement for your factory plastic coolant expansion tank. Made in the USA, all aluminum with beatiful TIG welding. Constructed with internal baffles and a machined aluminum neck that takes a factory cap. All of the inlets and outlets are positioned to match up with the factory hoses. The tank mounts to the same location as the factory tank and is built with the same dimensions for an easy fit. Includes view window on the side to check coolant level.

NEW optional satin black powdercoated finish offers a more subtle option than the bare aluminum. The satin black is a low-gloss finish that looks right at home in the NC engine bay, unlike a wrinkle or high gloss black that matches nothing around it. Some other examples of powdercoated tanks done by individuals or other shops make the mistake of coating the nipples where hoses and cap attach. That is a no-no! This premium powdercoating is done at the factory the correct way with all critical areas properly masked so that you get a great looking finish without compromises.

Stock plastic tanks are ticking time bombs because as they age they crack and when they crack the coolant pressure is lost and the motor overheats. Unlike the earlier Miata where an overflow leak was not big deal, the NC relies on this tank to be a pressurized part of the cooling system, as soon as a crack forms pressure loss causes the engine to overheat and the motor is usually destroyed. We have NC Generation Miata arriving on flatbed tow trucks every week with blown motors because the owner didn't change the plastic tank until too late. So we decided it was time for a "lifetime" solution. This tank is the solution. It will not fail over time like the factory tank, and looks great as well!

Installation NOTES:
While the factory squeeze-clamps on the hoses can be re-used, they get weaker the more they are removed/installed and having a tight seal on all the hoses is important since this tank is pressurized. We recommend changing the squeeze clamps out for worm drive hose clamps which can be found at any auto parts store. #4 worm clamp (x2) for the top two nipples, #10 worm clamp (x1) for the bottom.

Great write-up of the install process over on the Revlimiter blog:

YES, there is a view window on the side so you can see coolant level, see it in that window and you are good to go!

Optional satin black powdercoated finish!



Customer Reviews

NC Aluminum Coolant Expansion Tank

This is a well constructed piece that is not only functional but beautiful as well. I chose the black one and it looks like it came from the factory when installed. I have 75K on my car and plan to double that by doing prevention like this.

Excellent product - much sturdier than the oem plastic coolant reservoir tank (my oem tank had cracks and chips around the neck). Easy installation. Only issue I had was the holes in the hanger tabs seemed to be slightly off and, of course, no give (perhaps the only advantage of the plastic tank). Holding my mouth just right and wiggling the tank around, I finally got it to go over all three studs. Looks sharp and I fully expect it to long outlast the original plastic tank. Very happy with the purchase.

Nice piece of equipment. Was a fairly straightforward install. Most of the time was spent with the turkey baster tool sucking out the old antifreeze from the original tank. I did pick up some new clamps from the local O'Reilly's parts store. Gave me some more comfort. Used the same hoses as on the stock tank.

The fit and finish on this part is great and very easy to install. Looks very good under the hood.

I no longer have to worry about the flaws of the OEM tank. It is much easier to verify the level of coolant with the viewer on the side.

This is a peace of mind device. Extremely well-done welding. Car only has 23,000 miles, even with a cross North American jaunt. To be honest, the plastic tank did not appear to be at all deteriorated, but I'm sure it happens . Thanks Good-Win and Moroso!

Super easy install of a nice product. It really compliments my black engine compartment.


Fit like a glove. The tank was a very easy install and really is a great design. I have no complaints about the quality of the product. It really is an eye catcher when the hood is up.

First of all a big thank you to Sean for his typically good service. Also a big thanks to Brian and his team for developing this tank with Moroso. As noted by many, the fit and finish is excellent. My unit fits and looks better than OEM!

This is a must have item for your NC 2006 - 2015 period. I received mine a few days ago. Followed the directions on and it was easy-peasy! I did purchase a spill proof funnel and a gallon of Mazda FL22 along with a small hand syphon. All went well and now I can rest a little easier.

I set up my tripod and photographed the entire install. It is now posted on Meetup and my Miata Club (Sahuaro Miata Club) can see what is involved. Tomorrow night I have a club dinner and my "Show and Tell" will be this excellent product. I am sure Sean will get more business from SMC!

A must have item for every NC owner. As usual service from Sean was excellent. Package arrived, I installed it with ease. Everything lined up perfectly. I did use worm gear clamps. Picked up a spill proof funnel that everyone should have. Plus I picked up a gallon of FL22 coolant for top offs. The site glass is easy to read. It is positioned perfectly for viewing while topping off. It looks like a well thought out leak proof design. Now my Goodwin 2.5l MZR can rest a little easier in our Arizona heat.

While installing this expansion tank I set up a camera and shot the entire process. Now the Sahuaro Miata Club can see what a simple process this important upgrade is to install. I will feature this product at our next Monthly dinner meeting.

Once again a big thank you to Goodwin Racing for their efforts with Moroso in keeping our Miatas safe and even more bulletproof!

Well built, clean welds and prefect fit. 5-8 Minute job. Glass sight makes it fully functional and great for monitoring.

This tank is a top notch piece that you need to replace that questionable plastic one in your MX-5 ( many failures ) . It's a direct replacement and fits great. The only issue I've had so far is the fact that it gets very HOT, unlike the plastic tank, so don't touch it after a spirited drive.

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