HELP! Cam Shaft in. Briggs & Stratton 24hp V-twin Intek

[Stoa25]

I just got back from visiting my elderly father. While I was there he asked me to help him with his lawn mower. It was “hanging up” occasionally (nearly every time he turns the key) when he tried starting it. I adjusted the valve lash but the motor still hangs up. I’ve replaced cam shafts in similar motors due to the compression release mechanism failing. I’m seeing conflicting information online on whether or not this specific motor has a compression release mechanism. The model number is 445577, type 0435 E1. 24hp v- twin Intek. Can someone with much more experience that I have tell me if this motor has compression release mechanism? If it doesn’t, and the valve clearance is within specs, what else would cause it to hang up?

 

[farminkarman]

I just got back from visiting my elderly father. While I was there he asked me to help him with his lawn mower. It was “hanging up” occasionally (nearly every time he turns the key) when he tried starting it. I adjusted the valve lash but the motor still hangs up. I’ve replaced cam shafts in similar motors due to the compression release mechanism failing. I’m seeing conflicting information online on whether or not this specific motor has a compression release mechanism. The model number is 445577, type 0435 E1. 24hp v- twin Intek. Can someone with much more experience that I have tell me if this motor has compression release mechanism? If it doesn’t, and the valve clearance is within specs, what else would cause it to hang up?

I would assume it has compression release unless you find otherwise.

 

[EFSM]

Yes, this does have ACR. To my knowledge, the only B&S that don't are the big block Vanguards. I've never seen one fail though; they are way more reliable than the single cylinder engines, which fail routinely. You should be able to see the exhaust valve bump open on each side when the piston is nearing TDC on the compression stroke.

 

[Stoa25]

Thank you for your insight. Now that I know it most likely has the ACR I will look for the bump the next time I visit him.

 

[redline4]

Don't forget the starter, poor ground or crappy little battery cables they use either.
Once upon a time I raced mowers and we had some very heavily modified engines and had to use stock starters due to external stock appearing rules and we had no issues cranking them over with big cables and good batteries.

 

[Shane¹]

I just got back from visiting my elderly father. While I was there he asked me to help him with his lawn mower. It was “hanging up” occasionally (nearly every time he turns the key) when he tried starting it. I adjusted the valve lash but the motor still hangs up. I’ve replaced cam shafts in similar motors due to the compression release mechanism failing. I’m seeing conflicting information online on whether or not this specific motor has a compression release mechanism. The model number is 445577, type 0435 E1. 24hp v- twin Intek. Can someone with much more experience that I have tell me if this motor has compression release mechanism? If it doesn’t, and the valve clearance is within specs, what else would cause it to hang up?

Are you sure the valves are adjusted right? Not questioning you but just asking because I would recheck them 1 more time. I have set them wrong myself multiple times. You kinda have to adjust them a certain way with it at TDC if I remember right. You can't just go until one valve is closed and set it. Also someone correct me if I am wrong too. My 22 horse did the same thing until I finally got it right and has not messed up since