leeave96 490 #1 Posted May 16, 2013 I've got a 1988 and 1992 520H tractors and I read from time to time there were epa and non-epa carbs on these. How can you tell by physically looking. What year was the change over? Just curious. Thanks! Bill Share this post Link to post Share on other sites
boovuc 1,090 #3 Posted May 29, 2013 On the Pre-EPA mandates carb, (if it was never serviced), you'll see a plastic Phillips head adjuster on the idle mixture needle on the muffler side of the carb. It contains a limiter so that you can only change the setting a quarter of a turn. There are a few other differences but that limiting plug if it's still installed indicates the post EPA mandates verses the "Pre" years. Share this post Link to post Share on other sites
