snapper series 30 w/ briggs 217802 11.5p hp I/C starting nightmare

[Psychlopath]

I had this issue with a 12.5 IC L-head engine not too long ago. It was nasty enough that my electric starter would bog down...but I also have a slightly undersized battery on it for now.

It started after I replaced an exhaust valve that I couldn't get adjusted properly and was probably original to the engine, which has some serious hours on it. It was like there was too much compression...the best I could do was to gently pull the engine through 'till it opened both valves, then yank the cord or use the starter.

I checked valve adjustment again and put it closer to the max and it helped a great deal and it's still pretty easy to start with the cord or starter now.

I think I broke 3 pull cords, one of which let my elbow fly back and smash into the garage wall; there was much cursing and gnashing of teeth that day.

Good luck with it.

 

[kkelly311]

The latest is I discovered the recoil pulley wheel (that the rope winds around) had all of the plastic pins sheared off so I ordered a new one and also a new pawl plate and new pawls. Put it all back on and after about five or six pulls, at least one of the plastic pins has already sheared off allowing a pawl to fall out into the metal cup in the recoil area. This mower probably has less than 100 hours on it and I am now lost as to why this engine has become such a POS. From the beginning it was hard to start (high compression) and it got worse over time. I actually bought a different mower years ago so this Snapper has just been sitting garage kept (I am now working on getting it fixed and sell).

Can anyone offer any "what to do" from here? I was thinking about trying to start it with a cordless drill to see if that works.

Could I have a damaged valve that needs replacing? If so, is it very difficult?

 

[bertsmobile1]

Obviously something is preventing the engine from turning over.

Not enough compression release , check by removing the spark plug.
Problem goes away, rechceck the valve lash.

Problem persists, remove the head.
Problem goes away, bent or sticky valve, bent pushrod, valve hitting the head.

Problem persists Crankshaft / cam/ counterbalance problem and the engine needs to be stripped.

 

[Psychlopath]

The info on post #13 sounds pretty spot on as far as I know.

As far as how difficult the valves are to replace, I didnt find much of an issue. I did splurge on valve tool to remove keepers and springs and all that good stuff. I'm sure you could remove and install all of that with some creative pry bar use, but it was more of a pain in the sphincter than I wanted to deal with.

When I replaced an exhaust valve on my L-head because it had been ground enough that it was out of spec, I should have replaced valve guides as well....it used a TON of oil after a short while and, as far as I can tell, it was due to bad valve guides.

Have you done a compression check? If so, I missed what it read. If you have low or regular compression, we'll have to start looking into more of the mechanical issues, as mentioned in post #13.

 

[kkelly311]

compression should be fine although I have not checked it. Engine has less than 100 hrs on it so there should be no issue with piston or rings (oil changed regularly too). With all of the posts above and my assessment, I suspect it is a failed ACR on the camshaft. Found somewhere that this is common on this engine. Spinning the flywheel slowly does not cause one of the valves to have the small twitch as it should. I do have one question on the teardown..... is it possible on a snapper rider to tear it down without taking it off of the mower frame?

 

[577jersey]

compression should be fine although I have not checked it. Engine has less than 100 hrs on it so there should be no issue with piston or rings (oil changed regularly too). With all of the posts above and my assessment, I suspect it is a failed ACR on the camshaft. Found somewhere that this is common on this engine. Spinning the flywheel slowly does not cause one of the valves to have the small twitch as it should. I do have one question on the teardown..... is it possible on a snapper rider to tear it down without taking it off of the mower frame?

Not real familiar with that mower but usually you can get to the top end pretty easy,,but if you need to get at the cam,rod,lifters,or piston/rings you need to remove the lower crank bolts and split the case...and the motor will have to be unbolted from the frame for that.