Matt1961 4 #1 Posted July 2, 2017 So I have a K91 not sure if it's original to my 1961 551 but I replaced the following with all new: head gasket, carburetor, points, condenser, coil, plug wire, spark plug, oil and air filter..... now the question? Why does it not want to start when it's warm (op. temp) and some times cold. Low screw is 1 1/2 turns and high is 1 1/2 turn. Some only starts with starting fuild then fine for a little bit. Some times when it's hot won't start back up til it cooled down... Share this post Link to post Share on other sites
AMC RULES 37,143 #2 Posted July 2, 2017 (edited) From the manual... Edited July 2, 2017 by AMC RULES 2 Share this post Link to post Share on other sites
formariz 11,988 #3 Posted July 2, 2017 (edited) Original engine for that model was Tecumseh/Lauson H55B. Sounds like a fuel delivery issue. It can be problematic in those models since they are only gravity fed. Fuel line routing can have influence . Yours looks a bit short and stretched. Should loop down a bit so it allows air bubbles to move upwards to escape and keep constant fuel pressure. Try that first with a full tank. Float on carburetor may also be set a little low not allowing enough fuel in bowl. After running at High throttle , shutting it down and trying to start again there may not be enough fuel in bowl for it to start properly. Once it sits for a bit bowl eventually fills up. You just have to be patient and try these things. Its usually simple things. Sometimes if when it does not start try blowing into the tank to pressurize it a bit and push fuel into bowl. Sounds crazy but it works. If it starts after that you found your problem. Just make sure you don't go kiss wife after that. It will be the last time you do it. Edited July 2, 2017 by formariz Share this post Link to post Share on other sites
evanloock 221 #4 Posted July 2, 2017 Original engine for a 1961 551 is a Lauson H55D spec. # 2113. The 1960 550 used a Lauson H55B spec. # 1170. Share this post Link to post Share on other sites
formariz 11,988 #5 Posted July 2, 2017 Just now, evanloock said: Original engine for a 1961 551 is a Lauson H55D spec. # 2113. The 1960 550 used a Lauson H55B spec. # 1170. I stand corrected. Beat me to it. Thank you. Share this post Link to post Share on other sites