I repeated the leak down test on my 850 with a different test kit and ended up with the same results as my more expensive tester. The cheaper one is an OTC 5609 on line.
My tests using 100psi at TDC was 98 which = 2% leak down. I only use Polaris Extreme oil. Test done at room temp and motor cooled to touch after running. If you haven't done one before I would use something soft (like a Q-tip) to find TDC top dead center after pulling your spark plugs. Of course do 1 cylinder at a time, but you will need something or someone to hold the primary clutch from spinning once you add air pressure. Do not damage your clutch!! A clutch tool from SLP works great or you could be careful and use a wooden broom handle. Once I find TDC I put a sharpie mark on the end of the clutch bolt so I know it hasn't rotated under pressure.
1st pic is gauge hooked up before air pressure added.
2nd pic is with 100psi shown on left gauge, right gauge is how much the cylinder is holding.
3rd is Operating instructions. At the bottom you will see that my cylinder at 100psi held 98psi which translates to 2 percentage of leakage.
4th Cheap kit that can be ordered on line for cheap at less than 1/5th of my "good brand" that showed the same results.
5th OTC cheap compression tester. Didn't read as high as my higher $ tester, but it was consistent on several cylinders I tested. When I test compression with any tester, I only compare prior readings from the same tester for this reason. What is more important to me it the pressure differential between cylinders. For example if one is 130psi, and the next one is 115psi you have a problem.
6th is the cheap compression test kit part # 5606
7th is my reference above about marking the clutch bolt once you've found TDC.
Hope this helps.
![IMG_4607_1024.jpg IMG_4607_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245049-2e784a5d12dc9ebe1d82669b036126ef.jpg?hash=LnhKXRLcnr)
My tests using 100psi at TDC was 98 which = 2% leak down. I only use Polaris Extreme oil. Test done at room temp and motor cooled to touch after running. If you haven't done one before I would use something soft (like a Q-tip) to find TDC top dead center after pulling your spark plugs. Of course do 1 cylinder at a time, but you will need something or someone to hold the primary clutch from spinning once you add air pressure. Do not damage your clutch!! A clutch tool from SLP works great or you could be careful and use a wooden broom handle. Once I find TDC I put a sharpie mark on the end of the clutch bolt so I know it hasn't rotated under pressure.
1st pic is gauge hooked up before air pressure added.
2nd pic is with 100psi shown on left gauge, right gauge is how much the cylinder is holding.
3rd is Operating instructions. At the bottom you will see that my cylinder at 100psi held 98psi which translates to 2 percentage of leakage.
4th Cheap kit that can be ordered on line for cheap at less than 1/5th of my "good brand" that showed the same results.
5th OTC cheap compression tester. Didn't read as high as my higher $ tester, but it was consistent on several cylinders I tested. When I test compression with any tester, I only compare prior readings from the same tester for this reason. What is more important to me it the pressure differential between cylinders. For example if one is 130psi, and the next one is 115psi you have a problem.
6th is the cheap compression test kit part # 5606
7th is my reference above about marking the clutch bolt once you've found TDC.
Hope this helps.
![IMG_4605_1024.jpg IMG_4605_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245034-a8cb3d0e8c8814f061d6caed0054f85a.jpg?hash=qMs9DoyIFP)
![IMG_4609_1024.jpg IMG_4609_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245037-ca11a9e6e7bf8db5548de874e3636f58.jpg?hash=yhGp5ue_jb)
![IMG_4612_1024.jpg IMG_4612_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245040-7c424fae667c7987b5c14e2a2613e21a.jpg?hash=fEJPrmZ8eY)
![IMG_4613_1024.jpg IMG_4613_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245043-909226f2b6afc756106b0495d8120a7a.jpg?hash=kJIm8ravx1)
![IMG_4615_1024.jpg IMG_4615_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245045-d0ebd6eba3a481bd69976993ea1221e0.jpg?hash=0OvW66Okgb)
![IMG_4618_1024.jpg IMG_4618_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245047-58d6c6043cef99158ae9d8aab38d1ede.jpg?hash=WNbGBDzvmR)
![IMG_4607_1024.jpg IMG_4607_1024.jpg](https://www.snowest.com/forum/data/attachments/245/245049-2e784a5d12dc9ebe1d82669b036126ef.jpg?hash=LnhKXRLcnr)
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