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MKI Crosman Valve Stem Rebuild Kit
Quantity in Stock:30
Valve Stem Rebuild components for one Professional Rebuild of the Crosman MKI Exhaust valve Assembly. Can be used to fit many other models and other makers. Can rebuild the Crosman 454, 1600, 500, SA6, 44 and Hahn 45 It is not a copy of the Original Factory Part. For that reason we use a different valve spring with this head which is included in the kit. We use 100% Polyurethane seals so our guns DON'T Leak. Made in USA by Mac1. A propane torch can be very helpful to get the brass head to separate from the steel stem. The seal fits in the brass head and you use a 1/8" hole in a anvil to drive the head and seal onto the stem. It is a good policy to use a permanent thread locker in the brass head for insurance. Once the head is pressed together it can be trued and faced off to ready it for use. Heat the entire gun up to toasty when you first charge it so the seals will be supple and the pressure will be high. Making sure there is no damage to the valve seat where the seal sits is very important as the Mac1 seals are hard enough so you can leave the gun charged all the time. Getting it to seal initially can be impossible if there is any seat irregularity. Polishing the seat is often required to remove any scratches or abuse.
Because of minimal Valve return spring tension it is apprpopriate to cock gun before charging when using this valve and spring. It will give far better consistency and power but the valve can be held open by the hammer tension when the gun is NOT cocked so it is important to cock before charging.
If you use the parts that make for the most reliable repairs imaginable a DIY project can be the best investment you ever made in an airgun. Quality parts last. Your time is wasted when you use inferior parts.
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