Hi! I have a Bobcat 731,(1978 or around there I believe) It has a 4 cyl WISCONSIN gas engine. Unfortunately I have had nothing but problems with it. My friend (who is mechanically inclined & works on all kinds of machines) has tried a bunch of things, and nothing is working. The machine starts (with a little patience) and runs, but then all of a sudden it quits. Sometimes it will start back up and sometimes it won’t. The other night i noticed that it seemed to get worse as it got warmer, and my friend agreed. By the time we were down to the last 3 large squares of hay out of 16, he literally had to start it over & over 100 times, inching it forward. (He was not impressed with me, my horses, or the Bobcat when we finally finished at 2:30 in the morning! ♀️♀️). I can’t give you the full list of what he’s done, but some of the things I know of are: -changed/cleaned the gas filter -took the carburetor apart and cleaned it -new battery -put a fuel tank on top to see if that would eliminate the problem (It didn’t) - put a new electronic ignition on it (when I first got it) -I always use Premium Esso fuel I’m sure he’s done some other things, but I just can’t recall what at they are at the moment. (I can get that additional information later). In the meantime…has anyone else experienced this problem with Bobcats? Anything you suggest we take a look at or try (if we haven’t tried them already?)
What engine model? Guessing a VH4D maybe. As long as he has verified ignition and fuel, it sounds to me like it needs valve attention. They are well known for hanging and sticking valves as they get hot. As long as you are handling hay and bedding make sure the cooling fins are clean and open, chaff loves to plug them up and they are your cooling system. Easiest way to check them is to roll each cylinder up on compression when both intake and exhaust are (should be) closed. Apply air through the spark plug hole and listen for escaping air at the exhaust and carb intake. This will tell you if you have a valve that is not closing.
Hey Bill! Thank you for your reply. I will give him this information and let him check it out. With the way it stops abruptly, a sticking valve seems like a very possible reason. I will let you know how it goes! I’ll check that engine model number too! Thanks again! MUCH appreciated. patti