I have a 5hp b/s model 135202 and the start cord jerks back out of my hand BIG TIME! The flywheel key is a perfect fit. The original was a perfect fit but I put a new one in just to be sure. I removed the crankcase cover and the flywheel gear and the crankcase gear timing marks are aligned perfectly. I replaced the carburetor with a new one. I set the coil air gap, it was to close. Nothing is working. I still have the same problem. This motor is on a tiller not a mower.
Jerking Start Cord B/S 5hp Model 135202
- Thread starter dager41
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- Feb 19, 2020
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You are probably experiencing a compression kickback. Check valve clearance first. If they are correct check for ACR bump of one of the valve rockers as you approach TDC compression. If not there then you have a camshaft failure.
Here's were I'm at. I checked the valve clearance and the exhaust which is supposed to be between .009-.011 was .014. The intake is supposed to be .005-.007 was .024!!!!!! I was at tdc and rechecked my readings and settings several times. I pulled the head, removed the valve springs and rechecked everything and got the same readings. I removed the crankcase cover and removed the timing gear and the lobes measured the same height. Same for the length of the tappets BUT the intake valve measures in length a "heavy" 1/16 of an inch shorter than the exhaust valve, which accounts for .024 intake reading. I'm thinking that the exhaust valve is short too but I don't know what it supposed to be. Anybody got any ideas I,m sure open to listen. One question I have is how did it even run? Thanks in advance for you advice.
If the valves are that far out, then the engine has some serious hours. I will bet money that the feeler which runs against the ignition cam is also equally worn. This wear will change the ignition timing as badly as the valve adjustments changed.
FIXED! I ordered 2 new valves. Installed them, bolted everything back on and started on the 3rd pull. Thanks for the help