Chapin 6-8180 Piston Pump Repair Kit For Most Chapin Backpack Sprayers

This piston repair kit did the trick. Fits the Stanley Backpack Sprayer 61804N.

This fit the Stanley 61804N backpack sprayer I bought on Amazon in August of 2009 and it took care of the leak.I was a little worried when I saw that the piston pump collar was about 0.1in larger than the original. I called Chapin to be sure it was ok since other reviews say old sprayers may have smaller pistons. Chapin told me the small ones are about 1.5in and my sprayer and this kit are about 2in. If you get the wrong size, it will be obvious.Another new/old difference I noticed is that the old o-rings have a rectangular cross section. I don't know if that's from being squashed for 12 years or if it's just a change. The new round ones fit and worked fine. I did not replace the pressure cylinder o-ring since the sprayer's instructions suggest not doing that if it does not leak.A strap wrench came in handy to remove the piston cylinder.

This works well. You will need special tools to install this kit. You will not be able to unscrew the pressure chamber unless you have a great strap wrench.

No problems to date since replacement.

I purchased this kit for my 61804 Stanley sprayer I purchased at Sams Club. The Stanley sprayers are made by Chapin. Unfortunately, the piston collar did not fit the piston from my sprayer, even though Chapin's website shows that this kit is the correct seal kit for this sprayer. To hopefully save others a bunch of time, headache, and investigation please read this if you have a Stanley 61804:The piston collar does not fit OLDER 61804 Stanley sprayers (too big). If you purchased your sprayer 3-4+ years ago like I did there is a chance the replacement collar in this kit will be too large. I talked with Chapin Mfg. and they said they have no parts available for the older 61804 Stanley that I have. I suspect that the piston size must have increased in size at some point on the 61804 but have no information as to when. It MUST have changed size at some point in production as others here have reported that the piston collar in this kit fit their 61804, and the Chapin website shows this is the correct kit for 61804. (This 6-8180 seal kit is the same one sold on Chapin's website FYI.) It would be helpful if the Amazon seller or Chapin would provide the diameter of the piston collar included in this kit for folks with Stanley 61804 sprayers to measure and compare to the worn out piston collar prior to ordering.The seller shipped promptly and accepted the return of this item. The seals are good quality and appear to be Viton material.

After several years a few orings and seals gave out. Easy to replace except Piston Cylinder Assembly is hard to unscrew. I was able to use an oil filter wrench to hold the big tube while unscrewing the cylinder assembly. (May have to use channel lock plier on that end. Be Careful). Its tight. Unscrews normal direction. Get a tube of plumbers grease to reassemble. Used for faucet o'rings.

Fix my back sparyer

Wasn’t what I needed

Pump works perfect after replacing the seals. Way cheaper than purchasing a new pump.

worked perfect

Product as described fits well for repairs of backpack sprayer.

Excellent Piston Kit which I installed in the Base of my Chaplin Sprayer..In stalled easily an the pumping action was smooth an extremlly effiecint.

I paid good money for the Chapin sprayer. Unfortunately, the product is not very durable. The repair parts are 50% of the original purchase. While waiting almost a month for delivery I purchased another brand of sprayer for less than the cost of the Chapin replacement parts and it included a repair kit and gaskets Good bye Chapin