Sears 917370431 self-propelled lawn mower hard to pull start rope

[Cusser]

A couple of years ago I was given a Sears 917370431 self-propelled lawn mower from my neighbor. This started up fine and performed well, even though I'm not a great fan of its self-propelled feature, but that does work. Anyway, I recently hurt my right shoulder and have discovered I have pain and difficulty pulling the starting cord fast enough; it's several times tougher to pull than the two other Sears lawn mowers I have at a different site.

I believe the engine is B&S MODEL NUMBER 126M02-1525-EA, and there is no priming bulb on this engine. Any suggestions? Does this mower need valve adjustment to make starter cord pulling easier? I can guarantee that such adjustment has NEVER been performed on this (but I do know how to do this).

I have the owner's manual. Thanks.

 

[StarTech]

Being a L-head normally the valve clearance closes up making the ACR more active not less. But I have seen where ACRs fail on these camshafts creating higher starting compression.

Also the engine is using an auto choke system which is why there is no primer.

 

[Cusser]

Being a L-head normally the valve clearance closes up making the ACR more active not less. But I have seen where ACRs fail on these camshafts creating higher starting compression.

Are you saying that valve adjustment likely won't help me in this instance? And I should just wait until my shoulder feels better???? Thanks.

 

[sgkent]

when I start all my equipment, I pull the rope slowly until it is either all the way out, or I feel a lot of resistance. It will pull easily then suddenly sort of hit a hard spot. I then let the rope back in and pull it. The hard spot is basically the engine telling you, "hey, I am ready to fire and start." Usually it will start right away then without hurting my shoulder or back. I have taught the other half how to do this too because she would pull and pull and pull on it. If it does not get that stop feel before it is all the way out then do it again. If it is not ready to start after many soft pulls like this, it may need some kind of service - or the gas is old, etc..