I have a Murray self-drive mower with the B&S 6.75 motor. It is only 2 years old and is already giving me fits of frustration! The first symptom was not starting on a cool fall day ( Canada ). The second symptom was not hot starting after an intentional shut down. Now this marvel of design runs for 12-15 minutes with small misses and then shuts off. Wonderfull! I have ignored my instincts which tell me to remove the motor from the reliable Murray chassis and pound that B&S flat with a sledge hammer. Instead I have done all of the basic checks and cannot determine what the problem is. I have only basic mechanical knowledge, but my mechanically inclined friands are stumped by this. It seems to me the alot of these engines have the same problem and I was hoping one of your advisors knows exactly whats causing these troubles.:confused2:
If you would please post the model numbers off the engine, so we can see what you are looking at. I suspect either the carb needs cleaned or you are having issues with the smart choke system.
I need the model, type, and code off the engine itself, to determine which engine you have. There has been ongoing issues with the ready start, that seems to be intermittent, some people have all kinds of issues, and others never have a problem. What most people don't know is the carbs on the newer mowers are calibrated for 70 degrees F, and will be hard to start around 50 or lower. Most of the issues are tied to the bi-metal thermostat behind the muffler, It cools too quick, and closes the choke which causes no start when the engine is warm.
E-Z start is not advertised anywhere on the unit, unless you mean that the basic design is called E-Z start. (that would be funny) It has a primer bulb- pump 3x.:smile::smile:
The family name doesn't mean anything to anybody other than the EPA. either a spark issue with the spark plug, ignition module. could be something shutting off the fuel flow in the carb, or the fuel line from the tank.
#8
lawn mower fanatic
I moved your thread to the Small Engine & Mower Repair Forum. :smile:
they are stamped into either the flap that hangs out over the muffler, or above the spark plug on the blower housing. May have to look up under a plastic cover or remove the cover to see them.
Two common problems with that engine. One, people don't clean the jet in the bowl nut, and they get clogged and you get no fuel. the other is the air filter cover will warp preventing the primer from working. the fix for that is to double gasket the air cleaner housing to the carb.
ILENGINE...Thanks for the info, I'll clean the jet and see what happens. Since you might still be around, is there a factory setting(turns) for anything I'll be touching?
There shouldn't be any adjustments that you need to worry about. the only think to watch will be sometimes where the air cleaner housing mounts to the carb will waro, and the primer won't work. the fix is to double gasket the air cleaner housing to the carb.
Hi Folks. This is interesting We took it apart and cleaned the carb. The air filter gasget is in good shape. We put it back together and tried to start it ...no-go. Pulled the plug out and cranked it...no spark at all. I visit the local small engine parts shop, he says I need a new coil (ignition module 590454) $48.99 Cdn. Here's the interesting part- Inside the coil's box is a little slip of paper that says "AIR VANE REPLACEMENT If replacing the armature on an engine built before date code 101230xx, the original air vane must also be replaced. Order and install #790848 Air Vane (sold separately)" My engine has no original air vane that we can identify. No remnants or mounting hardware either. Also, the actual coil part of the coil is back about an inch from the flywheel on the new one. The old one has the coil part very close to the flywheel. The air vane is priced at $7.00 so I assume it is a little piece of plastic that directs cool air over the coil and down to the cooling fins. I'm wondering where it mounts. I had to order it after I got home, because the slip of paper is on the inside of the box. Anyway, this looks to me like B&S screwed up and this model of engine gets too hot and cooks the coil. No? The mower started on !st pull, but I'll wait for my air vane before I run it untill hot and see if it does the 12-15 min stalling routine. I'll let you know how this ends, for future reference. Thanks for all replies. It's good to know you guys are around!
I believe the air vane they are talking about is the governor vane, which your engine doesn't have. the old air vane governor will not work with the new style ignition module. so you have to replace the air vane. But since your engine has a mechanical governor, then you don't need it.
That is EXACTLY what my mechanically inclined friend said. So where do I stand here? This vane won't even work for me, but don't the manufacture date codes indicate that I should need this. Do I just run it with my new coil and if it"s reliable, forget about it. Am I confused or has B&S failed to specify the models included in this change. Do I have the right coil? :confused2:
I verified your part numbers, and they are correct. the air vane that you need is for the autochoke/ready start system. I forgot about that air vane. Yes you need the new air vane after all.
Still waiting for the "Mysterious" air vane. I had to actually push my back-up mower around the lawn. Yes. the grass in Canada is actually growing! My Murray is self-drive. and so much easier.
