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Anyone out there have this engine? Been meaning to ask this for years. The snapper model did not come with an electric start. I must say, the recoil starter on this engine is the most frustrating thing I have ever seen. First, unless you wear gloves trying to start this, you will quickly learn to. Here are the four issues I have had with this engine:

1) you put foot on rear tire and pull starter rope..... flywheel does not spin very far (high compression perhaps) and the entire mower comes off the ground (wheel on other side comes off the ground). This puts a pretty good jolt to your shoulder and your hands.

2) you put foot on rear tire and pull starter rope.... flywheel turns and then the system yanks the starter t-handle out of your hand so hard that it actually over time has chipped the corners of the t-handle and once hit the oil dipstick handle so hard it cracked it. This also can inflict some pain on the hands, etc

3) you put foot on rear tire and pull starter rope and it turns over normally (although not easy), but you are on edge because you think number 1 or 2 above is going to happen.

4) you put foot on rear tire and pull starter rope and the starter pawls basically pop out of the little slots inside and you have to take the thing apart and fix..... only to experience all of the above again.

5) you put foot on rear tire and pull starter rope and the actual knot inside the t-handle fails and the rope gets sucked into the recoil. Number 5 happened only when I changed the recoil rope and the knot kept failing (even after a slight melting). The failure was due to the enormous amount of tension on the rope when all of the above are happening.

Has anyone else experienced this? I know the solution would be to add an electric start to it, but I cannot even get Briggs to tell me if one will work (how unreal is that .... they don't even know their stuff even though I recall the model number of the snapper ending in BV and seeing one in the manual as BVE [which I gather means it has electric start].

I'm not familiar with your particular engine model, but you appear to have a compression release that is not working. Electric start won't help this either. You need to find out what is wrong with the compression release, or possibly you have too much valve clearance which could render the release useless, or less effective.

Mojoe is right,I had a 420v that was a damn bear to start,,would rip my shoulder out...the valves where so loose the ACR would not even function,,soon as i set the valves to .004 the problem was gone...Ive seen a sheared crank key do this also...but thats rare on a belt drive.

Also,does the mower run fine when its started or does it smoke,,reason being the crankcase might be full of fuel causing a hydro-lock.
Easiest way to rule that out is check oil level.

Tom

577jersey said:

Mojoe is right,I had a 420v that was a damn bear to start,,would rip my shoulder out...the valves where so loose the ACR would not even function,,soon as i set the valves to .004 the problem was gone...Ive seen a sheared crank key do this also...but thats rare on a belt drive.

Also,does the mower run fine when its started or does it smoke,,reason being the crankcase might be full of fuel causing a hydro-lock.
Easiest way to rule that out is check oil level.

Tom

Click to expand...

Once mower is running, it is fine (no smoke). I did check valve clearance this morning and there was zero clearance. Would this cause the issue.... logic tells me yes? Seems that everything I have read, issues were too much clearance (valves too loose).

I wish I had more to add, but I am not familiar with this particular engine. I have been out of the mower business since 1995.

Not sure how that engine is set up but on the ones I saw if valves where too loose the ACR would not function cause it works off the cam and if the valves are too loose the lobe used to push the valve open a hair never gets close enough to push it open until the proper adjustment is made.

Too tight valve clearance may result in the valve or both valves being open at the wrong tight, causing your problem. Set both valve clearances at .005" and turn the engine through 5 cycles. Check valve clearance again. If they are not at .005" reset and continue until you get .005" every time. At this time rotate the engine very slowly watching the intake valve, you are looking to see if it opens a hair on the bottom of the compression stroke, meaning the compression release is working. After doing all this you still get kickback, time to check and/or replace the flywheel key.

I adjusted the valves and it helped but I am going to take flywheel off. I assume I will need a piston stop and take the 15/16 bolt off the top and then I see what looks like two gold colored hex bolts with T-30 torx to get the plastic fin piece off and then use a puller to get flywheel off and the key/pin is underneath correct?

You don't always have to remove the flywheel to see if the key is sheared. Once you remove the flywheel nut or bolt look at the area where the crankshaft goes through the flywheel. Most of the time you can see whether the key is sheared before removing the flywheel. If you must remove the flywheel, down load a B & S manual and it will. Show you how to pull the flywheel safely, without damaging anything. It doesn't have to be totally sheared to cause a problem, so you will probably have to remove the flywheel either way, someplace it with a new key on reassembly.

pulled flywheel just to check the key and it was all OK. Will put it all back together and see how it all goes

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.

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?

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.

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.

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?

kkelly311 said:

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?

Click to expand...

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.