I have a 1990’s model yardman snowblower, 5hp 22″. Lately it doesn’t seem to be able to handle much snow. It boggs the engine down when I get into snow much more than and inch or two deep. I checked the auger drive belt and adjusted some slack but it didn’t help. I also checked the auger shear bolts, they are okay. I removed the fuel tank and emptied it and replaced the fuel. I also removed the fuel line to check for obstructions. I put a carb kit on it earlier this winter and it seemed to work just fine. Any suggestions?
Gary, Without knowing the exact model number of your engine, I can only guess that it is an Tecumseh HS series. If it is, we have seen problems with the valve clearance. The engine starts and seems to run ok, but it will lack power. Originally the valve clearance spec was .010 on each valve, then they put the spec at .004 – .010. This is when we started to see this problem. We set them at .010 and this seems to remedy the problem. Do a compression check, if it is less than 100# after 3 pulls, then you could have a valve clearance problem. If you don’t have a compression guage, you will need to remove the breather assy to gain access to the valves. With the piston 1/4″ past TDC, usa a feeler guage to check the cleaeance between the valve stem and the lifter. If it is not correct, the valve will have to be removed and the stem ground off to gain the correct clearance. Joe