theoldwizard1
Member
- Joined
- Sep 9, 2012
- Threads
- 13
- Messages
- 36
So I think I am above average when it comes to repairing small engines, at least older Briggs and Stratton single cylinder. But I kind of got my butt kicked recently by a B&S Quantum vertical shaft !
So back in June, I dragged my pressure washer out to clean the underside of deck, something I do a couple times a year. Hook up the water and the high pressure hose and gun and ... NO START ! Well, it has been sitting in the garage for more than 6 months with fuel in the tank (and no fuel shut off). I immediately assume (yeah, yeah, yeah) the the carburetor is clogged up. Pull the carb, disassemble, (hmm, looks clean?) soak in carb cleaner over night. Reassemble the next day. Still no start. I shot of carb cleaner straight down the throat. Pull the cord. NOTHING !
Time passes.
Finally, get out my spark tester. No spark ! (Or the dummy had the throttle in the OFF position grounding out the coil !) Well, coils/magnetos aren't that expensive, so I order one and a spark plug.
More time passes.
New coil, new plug. Spark ! (By this time I had removed the kill wire.) But still no start ! I had installed a fuel shut off valve (I had one in my small engine spares drawer along with fuel line and spring clamps) so that was a bonus.
More time passes.
Okay, let's get serious. Start looking around and it looks like the head gasket may be leaking. I had one in my spares so I might as well install it. Clean the gasket surfaces and spin the crank. Reassemble. Still NO JOY ! Pull out the compression gauge. (Probably only the second time I have used it in 50 years. Sears/Penske.) ZERO !
More time passes.
So a couple days ago I'm think. Why no compression ? I know that engine (B&S Quantum) does not have a compression release, so it can't be that. Then I realize. Were both valves opening and closing fully ? Maybe not ! But what would cause a flat head valve to NOT CLOSE fully. I start checking YouTube. Sure enough, there is a guy with the same problem ! The valve is stuck in the guide and the spring is not strong enough to close it.
But I don't own a valve spring compressor. Amazon. Time passes.
Today, I pull the head, exhaust, side cover. A few minutes fiddling with the valve compressor and the valve is out. It is clean. Small nylon brush and I clean up the guide. Reassemble. (Sure goes fast after doing it 3 or 4 times.)
Starts on the second pull ! Left the kill wire disconnected and will use the fuel shut off.
So back in June, I dragged my pressure washer out to clean the underside of deck, something I do a couple times a year. Hook up the water and the high pressure hose and gun and ... NO START ! Well, it has been sitting in the garage for more than 6 months with fuel in the tank (and no fuel shut off). I immediately assume (yeah, yeah, yeah) the the carburetor is clogged up. Pull the carb, disassemble, (hmm, looks clean?) soak in carb cleaner over night. Reassemble the next day. Still no start. I shot of carb cleaner straight down the throat. Pull the cord. NOTHING !
Time passes.
Finally, get out my spark tester. No spark ! (Or the dummy had the throttle in the OFF position grounding out the coil !) Well, coils/magnetos aren't that expensive, so I order one and a spark plug.
More time passes.
New coil, new plug. Spark ! (By this time I had removed the kill wire.) But still no start ! I had installed a fuel shut off valve (I had one in my small engine spares drawer along with fuel line and spring clamps) so that was a bonus.
More time passes.
Okay, let's get serious. Start looking around and it looks like the head gasket may be leaking. I had one in my spares so I might as well install it. Clean the gasket surfaces and spin the crank. Reassemble. Still NO JOY ! Pull out the compression gauge. (Probably only the second time I have used it in 50 years. Sears/Penske.) ZERO !
More time passes.
So a couple days ago I'm think. Why no compression ? I know that engine (B&S Quantum) does not have a compression release, so it can't be that. Then I realize. Were both valves opening and closing fully ? Maybe not ! But what would cause a flat head valve to NOT CLOSE fully. I start checking YouTube. Sure enough, there is a guy with the same problem ! The valve is stuck in the guide and the spring is not strong enough to close it.
But I don't own a valve spring compressor. Amazon. Time passes.
Today, I pull the head, exhaust, side cover. A few minutes fiddling with the valve compressor and the valve is out. It is clean. Small nylon brush and I clean up the guide. Reassemble. (Sure goes fast after doing it 3 or 4 times.)
Starts on the second pull ! Left the kill wire disconnected and will use the fuel shut off.