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MSM check valve kit

MSM check valve kit
MSM check valve kit

Make the oil separator in your MSM work as Mazda intended!

Exclusive to Flyin' Miata

Availability: In stock



The stock Mazdaspeed oil separator is a good idea, but not a great execution. Under hard driving, oil can actually work its way up through the drain tube and enter the intake. This means a lot of oil consumption and an increased risk of detonation as well as carbon buildup in your engine. A lot of Mazdaspeed owners have removed the separator, but now there's a better option.

This check valve goes in the drain line and allows oil to drain back into the pan - as Mazda intended - but prevents it from going the wrong way. The valve has a very light opening pressure to keep the oil from backing up in the drain hose and is designed to work with higher temperatures and oil. Includes all hardware, easy 30 minute installation.

Additional Information

Additional Information

Part number 36-90100
Fits: MSM
Manufacturer No
Flyin' Miata exclusive Yes
Fits Exocet? Yes
Proposition 65 Warning: Cancer and reproductive harm
California emissions No information at this time

Customer Reviews 1 item(s)

Great addition
I installed this on my MSM when it had 116K miles. I cleaned the intake manifold before installation, it had so much baked on oil that I went through at least 3 cans of carb cleaner. The car now has 156k on it. The intake looks as good as it did when I cleaned it. This is a great addition to the car.
Review by Gladu / (Posted on 7/8/2017)
Click here for instructions for this part.

Why stop here? Consider this upgrade.