PART NUMBER: 61-2037B
Direct replacement for your factory plastic coolant expansion tank. Made in the USA, all aluminum with beautiful 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.
Option is to add a high performance KOYO 1.3 bar (19 psi) radiator cap. These tanks are compatible with the factory cap, so replacing the cap is not mandatory, but if you need a replacement for your used factory cap then this is the best option, and higher pressure than the factory 16 psi cap!
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.
As these cars age, the factory plastic tank is a common failure point because the plastic gets brittle and cracks. Unlike the earlier cars where that just meant a leak, the NC relies on this tank to be a pressurized part of the cooling system, which means that as soon as a crack forms the system loses pressure and the engine overheats. We've had more and more people bring in cars with blown motors due to this simple failure, and along with a new expansion tank now they need a new motor as well, 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!
CLAMPS: 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.
CAP: You might need to very slightly adjust the 'tangs' on the factory radiator cap to fit the new metal neck with same tension as it did on the factory softer plastic neck, takes a few seconds to do with pair of needle nose pliers.
Great write-up of the install 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!
Great product, quality build and beautiful construction.
Installation is straightforward and easy. My only caution: be careful and don't drop a hose clamp, you'll spend more time digging it out of the depths than actually installing the tank HA!
Power steering reservoir is next.
Great piece of peace of mind for my Miata. Seems very well made and easy to install myself. Very happy with it.
Great looking product that brings peace of mind over the old plastic expansion tank. Easy to install, but recommend the screw clamps. Treat your Miata right and upgrade today.
A must for any MX-5 owner, never again worry about coolant tank leaks or break. Easy to install and it looks great.
Great product, performs described job well. Install took about 10 minutes. A little bit of weld slag on the tank I received, but not enough to complain. The only negative I will say is because it is Aluminum, it does get fairly hot after a drive. But is a lifetime solution to a common problem on NC's.