Is there any way to check the timing of a 23.0 Hp Vanguard model 386447-3079-G1 engine using a 12V powered timing light? I understand the timing can’t be adjusted, but I was hoping the timing could be tested to determine if the flywheel key may be partially sheared.
Last fall I installed the new engine to repower a John Deere 318 Lawn Tractor with 44” mower deck. The engine now has about 7 hours on it, and the tractor has about 1500 hours. Last fall everything ran just fine. It started good, accelerated quickly and had power to spare while under full load.
I noticed over the winter when I was pushing snow it started running rough, seemed to be somewhat lacking in power & top RPM, would occasionally stall out and have to be restarted. I attributed a lot of that to the cold conditions and the “push till you spin out” loads I was moving.
This spring after I put the mower deck back on, it now runs rough, struggles to run above 1/3 to ½ throttle, will only accelerate while SLOWLY advancing the throttle lever to full speed, barely has enough power to move the hydrostatic tractor at creep speed, dies repeatedly, and occasionally backfires up through the carburetor. Even with the engine running at maximum governed speed, it will die when the electric mower clutch is engaged. All of the mower blades & idler bearings seem to be turning freely, so I don’t think that’s the issue.
I have the complete Vanguard OHV Repair Manual, but I am stymied as to what is causing my issue. My in-line neon spark tester shows I have consistent spark on both cylinders at all RPM. I’ve replaced both Champion XC92YC factory sparkplugs with NGK BKR5E-11 (Stk 6953) plugs. I did find one of the factory plugs was black and wet when removed.
I have cleaned the air filter & foam, and the engine performance does not change even with the air filter absent from the engine. When I did the repower last fall, I removed the fuel tank from the frame, and attempted to remove any sediment by turning it upside down & shaking the remaining fuel out of it. I also replaced all fuel lines inside and outside of the Deere tank, and cleaned & re-attached both submerged fuel pickups inside the tank.
I’m willing to try any suggestions from the group, but I’m leaning toward the possibility of a partially sheared flywheel key. Again -> Is there any way to test the timing of the engine using a timing light? Unless someone has a better idea, the only way I can see to inspect the flywheel key (in this application) is by completely removing the engine from the tractor frame; approximately an all-day project for the out & in.
It’s not something I’m looking forward to doing AGAIN and I’m too cheap to pay someone else to do it, but if you say I have to........!
Last fall I installed the new engine to repower a John Deere 318 Lawn Tractor with 44” mower deck. The engine now has about 7 hours on it, and the tractor has about 1500 hours. Last fall everything ran just fine. It started good, accelerated quickly and had power to spare while under full load.
I noticed over the winter when I was pushing snow it started running rough, seemed to be somewhat lacking in power & top RPM, would occasionally stall out and have to be restarted. I attributed a lot of that to the cold conditions and the “push till you spin out” loads I was moving.
This spring after I put the mower deck back on, it now runs rough, struggles to run above 1/3 to ½ throttle, will only accelerate while SLOWLY advancing the throttle lever to full speed, barely has enough power to move the hydrostatic tractor at creep speed, dies repeatedly, and occasionally backfires up through the carburetor. Even with the engine running at maximum governed speed, it will die when the electric mower clutch is engaged. All of the mower blades & idler bearings seem to be turning freely, so I don’t think that’s the issue.
I have the complete Vanguard OHV Repair Manual, but I am stymied as to what is causing my issue. My in-line neon spark tester shows I have consistent spark on both cylinders at all RPM. I’ve replaced both Champion XC92YC factory sparkplugs with NGK BKR5E-11 (Stk 6953) plugs. I did find one of the factory plugs was black and wet when removed.
I have cleaned the air filter & foam, and the engine performance does not change even with the air filter absent from the engine. When I did the repower last fall, I removed the fuel tank from the frame, and attempted to remove any sediment by turning it upside down & shaking the remaining fuel out of it. I also replaced all fuel lines inside and outside of the Deere tank, and cleaned & re-attached both submerged fuel pickups inside the tank.
I’m willing to try any suggestions from the group, but I’m leaning toward the possibility of a partially sheared flywheel key. Again -> Is there any way to test the timing of the engine using a timing light? Unless someone has a better idea, the only way I can see to inspect the flywheel key (in this application) is by completely removing the engine from the tractor frame; approximately an all-day project for the out & in.
It’s not something I’m looking forward to doing AGAIN and I’m too cheap to pay someone else to do it, but if you say I have to........!