pittymk 0 #1 Posted May 29, 2011 I have a new to me 88 520-H for the most part has been running pretty good since I replaced everything with the fuel system except the carb. In the last week after about 45 minutes of use, I've started to get some surging in the 2500rpm to 3200rpm range when the PTO is activated. the surging usually will stop after i disengage the deck. would one think that the carb needs to be tweeked? i'm also having some issues starting some days. it sometimes takes a few cranks to get it right. The manual says 1/2 choke, 1/2 throttle...... Share this post Link to post Share on other sites