200 Pro Max compression

[Hank W]

I checked the compression on my 200 PM Sunday and the readings were all right around 130. This is with 35 1/2 CC heads cut by Ruck. Back in December the readings were all around 140 w/ the same gauge. Is this due to different weather conditions or is it due to wear? Comp. was 115 with the stock heads. I know these #s differ from gauge to gauge, but these were all done w/ the same gauge. This motor is a 96 model that I put into use in the summer of 97 and has around 125-175 hours. The reeds look good. Is it reringing time?

[Jay Smith]

Hank ,
There are several factors that effect compression readings.
Ring wear, O rings in your compression gauge, starter condition , oil amount in the bores , ambient temperatures outside, temperature of the motor , throttle bore (s) position and battery condition. Most all these conditions can cause differences in compression readings. I would opt for the leak - down test for my final dission for a re ring job . They can be bought from Jegs or Summit for around $60.00 of a Snap - On is around $300. No matter the way anyone tells you the way to do these tests you much choose the way that is correct for your situation and do it the SAME WAY every time .....

Good luck Hank ,

[Hank W]

Do these leakdown testers come w/ instructions or do you have a preferred method that you would recommend? I'll pick one up from Summit or Jegs. Thanks,Hank