79horse 0 #1 Posted June 18, 2012 Got a 1979 c-141 and it will mow for about an hour and then it just dies. Will try to restart and it just turns over and won't fire. Take the gas cap off and blow air into the tank and it will start right back up and you can continue mowing, It has happened 3 times now and about the same place everytime. Just trying to figure out where to look 1st. Put new spark plug in, dropped gas tank and cleaned out and put new gas line from tank to pump, new air filter. Any help is appreciated and I am a new user. Thanks Share this post Link to post Share on other sites
COMMANDO6 20 #2 Posted June 18, 2012 :WRS: But sorry I can't help answer you're question. But there are many helpful people on here who can help you out. Share this post Link to post Share on other sites
roscoemi 245 #3 Posted June 18, 2012 Make sure the gas cap vent is not plugged or that it really does have a vent. Sounds like your running long enough to create a vacuum in the tank, then releasing it when you remove the cap. Russ 1 Share this post Link to post Share on other sites
RCTruckDaddy 8 #4 Posted June 18, 2012 If it runs with cap off then the vent hole in cap is plugged. Share this post Link to post Share on other sites
79horse 0 #5 Posted June 18, 2012 I have ran it without the cap the last time and it didn't seem to make a difference, so not sure that is it Share this post Link to post Share on other sites
79horse 0 #6 Posted June 18, 2012 The cap has the guage in it and the plastic that goes over the guage is broken and I can see right down the center of the cap as that is where the float goes. Plenty big enough hole in the cap for venting I would think. It just seems like it is the same time about every time. Runs great up to that point and after blowing air in the tank it runs fine after it dies. Not sure if the pump gets warm and quits but I am at a loss. Share this post Link to post Share on other sites
SAM58 30 #7 Posted June 18, 2012 The tank valve has a screen on it that is stopping up. replace it for about 14.00 should fix your problem. Had a 520H that did the same thing, if for some reason that doesn't do it. Blow out your fuel lines from the tank to the filter (replace) and clean the carburator bowl... It's just starving for fuel. My .02 cents 1 Share this post Link to post Share on other sites
Don1977 604 #8 Posted June 18, 2012 I know that they will run for a while after setting with a bad fuel pump. I don't remember had long ti will run before it quits.. I had a bad fuel pump and it acted that way. You could let it set for 20 mins. and it would start back up. Could be the filter screen or the fuel line comming apart inside stopping the flow. Share this post Link to post Share on other sites
AMC RULES 36,963 #9 Posted June 18, 2012 Agreed, sounds like an issue with the fuel pump to me too. Share this post Link to post Share on other sites
SousaKerry 500 #10 Posted June 18, 2012 Try another coil, I had one that would cut out when it got hot, let it cool for a few hours and it'd fire right back up Share this post Link to post Share on other sites
79horse 0 #11 Posted June 18, 2012 I wondered about the coil also, but when it has stopped i take the fuel cap off and just take put my mouth right over the tank and blow air into it and the tractor will start right off, without ever cooling for over a minute or so. That got me thinking about the pump and I am sure it is fuel related so I will try some of the suggestions posted earlier. thanks again everyone. Share this post Link to post Share on other sites
Don1977 604 #12 Posted June 18, 2012 I forgot that your 79 had the tank under the seat, I don't think they will run with out a fuel pump. The older models with the tank behind the dash will run with a bad pump they will still cut off but you can wait 20 minuets and they will start back up. Check if the connections on the fuel lines are tight it could pull in air and lose prime to the pump. Share this post Link to post Share on other sites
skrusins 128 #13 Posted June 19, 2012 I cleaned and re-gaped my points and that work for me so far. If mine continues to run I'm going to replace the points and condenser Share this post Link to post Share on other sites
can whlvr 991 #14 Posted June 19, 2012 it sounds like you need an in line spark tester to tell you if it is spark or fuel,you carry it with you and when it dies put the tester on to see if she has spark Share this post Link to post Share on other sites
