Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

my simplicity pro was running great last week, and now won't start. i cannot pull the starter rope unless i remove the spark plug. i took apart the carb bowl, removed the float and needle and sprayed with carb cleaner, re-assembled, no better. i squirted some gas in the cylinder, replaced the plug, no difference. it has electric start, i have popped the GFCI several times at the outlet. not sure what to do next!

I assume its an OHV engine?.. if so I would check valve clearance first... we do need some more info like model# what make of engine?.. there should be a label on the motor take a picture of it if u can that's seems to be the easiest way I find..

could be the starter motor hanging up on the flywheel ring teeth? i would start there and see if removing the starter free's it up. if it's not the starter remove the plug and turn the engine backwards by hand for a turn or two and then try the pull cord. if you can turn the engine place a pencil in the spark plug hole to see if the piston is travelling up and down as you turn the engine by hand .rule out the simple things first and hope for the best.

briggs and stratton snow king , with a nikki carb

<BR><SPAN CLASS="quotedmessageheader">mtbmike wrote:</SPAN><BR><DIV CLASS="quotedmessage">briggs and stratton snow king , with a nikki carb<BR>[/qu<BR><BR>


is engine OHV?

I would stop trying to use the electric start until after you find out what is locking the engine. All that will do is break something. My guess is oil or gas in the cylinder causing a hydro lock? Could be the valves need adjusting and the compression release isn't working as well. I have heard of flywheel magnets coming loose and wedging, but that doesn't explain pulls fine with no plug. Also, someone suggested checking the oil level on another forum. Apparently if the oil gets too full it will hydro lock the piston on the down stroke.

Shryp, if it were oil causing an issue on the downstroke, I'd expect the oil might try to blow out of the crankcase breather as the piston went down and you pressurized the crankcase? Just wondering.

But I would, for instance, sniff the dipstick and/or the oil fill tube, to see if you smell gas. It's possible that gas is leaking into the crankcase (from something like a stuck float/needle valve in the carb), filling the crankcase. Is the oil level correct? If it has more "oil" (possibly also gas) than it did last time, you likely had gas leaking into the crankcase.

If you remove the plug, and pull the cord fast a few times, does anything spray out of the sparkplug hole? Like Shryp said, if you have a cylinder filled with gas/oil, you would be unable to pull the cord with the plug installed. But you might see some come out if you spin the engine over quickly with the plug out.

argh... i took the valve cover off and there was a piece of rod about 6 inches long hanging out of one of the holes. i pulled it out, it wasn't connected to anything. what the heck is it and what's next, take the head off? thanks for the help so far!

If you're under the valve cover, and there's a long straight rod, that sounds like it could be a pushrod.

I haven't worked on a Briggs OHV snowblower engine, just a Briggs OHV tractor engine. But on that, and my Tecumseh OHV snowblower engine, the pushrods were trapped under the rocker arms, and shouldn't just be moving around freely.

I'm trying to think of a reason why it wouldn't turn over without the plug removed, but also had a pushrod loose. Is the rod straight and undamaged?

If the pushrod in question is the one for the valve that provides the compression release (maybe exhaust?), I guess that could make sense. You'd have no compression release at all, so you'd be trying to push the piston up into a fully-sealed chamber, which would be much harder. I don't know *how* hard, though, whether it would be so bad that you couldn't turn it over with the pull-starter.

Do the rocker arms (the pivots between the pushrods and the valves) look OK?

Sounds like pictures might help.

please note that i COULD pull it over with the plug out. it's back together now but here's a couple pics i took today

sorry the pics are so huge

Yea, that is a pushrod. It is suppose to be straight. You will probably need a new one and make sure the rockers didn't get damaged as well. Sound like maybe you were over due for a valve adjustment and it got loose enough for the push rod to come out from under the valve. The other thing could have been the valve was hanging up some how and you forced the engine to turn over and that bent it.

should i attempt to repair? i read online that in most cases like this the cylinder wall will be scored and ruined as well. i can buy a replacement engine for around 450, but not sure i want another briggs like this. this is 3 years old; first time i've ever had a problem with any small motor. I have to say, this simplicity pro has been nothing but trouble since day one.

Did the things you read say why the cylinder would be scored? If you "just" had a pushrod come loose for some reason (say the rocker arm locknut came loose), I wouldn't have expected that to score the cylinder. But maybe there is some root cause that would explain cylinder damage.

But I'm no expert. I'm honestly just asking.

Maybe straighten the rod and put it back together. See if it will run. If all seems good get a new rod and put it back together. What size engine is it? You can get a 7HP replacement at Harbor Freight for under $100.

mtbmike wrote:
Well ur making progress :)... Its VERY unlikely that there's any cylinder damage... if it was me I would order a new push rod and install it 90% chance that will fix it.. u need to know how to adjust valves correctly or u will have future issues.. most likely reason why the push rod got bent was it became to loose while running.. there alot of u tube videos on how to adjust valves if ur not sure..

just wanted to add my thoughts on these briggs motors as u mentioned having issue from day 1... I work on these motors alot and will say there are a very reliable motor as long as there maintained... for example if u never had this engine tuned up or the valve clearances checked within the 3 years you've owned it then that's an a problem.. most consumers buy snowblower or lawnmower and don't realize they need yearly mainetance... I would NOT give up on this motor especially for a bent push rod its a simple low cost fix...

From the picture I can see that rod is bent, period. So now I will assume the valve was tight and that's why it bent over time. Lastly, it is so bent that the valve stayed closed causing so much pressure in the cylinder that the motor couldn't turn over and that is why the GFCI circuit tripped as the starter amperage increased trying to overcome the piston pressure.

thanks a ton, guys. the simp came misadjusted, wouldn't throw snow. i know i should have just fixed it myself but after years of fixing my broken stuff and just paying 1800, i told the dealer to come take it back. 4 weeks later after numerous calls i finally had it back, unrepaired. several other issues, none engine related, soured me on this bad boy. the engine has run fine since day one before this. i believe this happened because i put it away wet in 10 degree temps and it froze up, and then i tried to start it while frozen. maybe it was stuck in gear or somehow engaged, i'm just guessing here. i'll try to find a rod local today after work, otherwise i'll straigten and see if i can get it together.

Mike, don't go that direction. If it's bent it is DONE. Don't try to straighten that as it's not possible to get it perfect again. If you went that route you will be back and do greater damage second time around. Look up the part # and get new. On the Internet they are available from many places as this is a common part.

got ya. i have already called the local shop, they need my exact model number, so after work i will get home and call them. i am planning to just use new. $5 list! hahaha. it this works i will have saved $$ edit: wow i re-read this and i sure sound like a greedy little miser! maybe the wife is right.

i can't figure out where the new push rod seats in the head. i could see a little hole or socket in there, but when i put push rod in there it didn't move.
it seems if i just leave it laying loose it works the valve, but that doesn't seem right at all. the other push rod seems nice and snug. Also, the pushrod came with a tappet - no idea where that goes! 

so that last pic is kinda misleading.. it's the other end i can't figure out. can barely see in there with a flashlight, and there is a puddle of oil on the bottom, approx where the intake pushrod is sitting on the other side.

The centre bolt on the rocker arm (it says 8.8 on it) remove it then you will be able to see in there better.. it is very important that u get the push rod seated properly.. here's a web site of guys that's has some really good videos on adjusting valves.. www.smalleng.com

yes, i did take the center bolt out, i also loosened the rocker enough to swivel it out of the way. i couldn't see down where the push rod probably needs to connect because there is oil in there. I'll drain it tonite and see if that helps. thanks for the videos, but i watched about 20 last night, and can't find any one that shows where the rod connects.

i've seen some pics that look like the tappet goes on the bottom of the push rod, towards the crank. Is that my problem, i didn't use it?

From what I recall on my Tecumseh, the pushrods seated onto little recesses or something, and were kept in-place by being trapped under the spring-loaded rocker arms. They didn't screw in or anything like that, I just dropped them onto their locations. If the tappet is still in there, I'd imagine you wouldn't have to do anything with it?

thank you. I did see 2 indentations and seated the push rod in one, and pulled the engine over slowly. the rod didn't move. when i place the rod lower, sitting in the oil puddle, it DOES move. I attempted to lock it down by using the adjusting torx screw and nut, but then had too much resistance when i tried to turn it over again. does no one know where the tappet goes? i sure didn't find any tappet when i originally opened the value cover, maybe it dropped down into the oil pan?

Merely speculating, that's deeper inside the engine than I went.

But I'd expect the tappet to sit on the camshaft, and to have the little recess on it. When you look down inside the engine, does what you see look like the included tappet that came with the pushrod?

Does the other pushrod move when you slowly turn the engine? If not, perhaps something went wrong with the camshaft?

ah, here's a new ominous clue. the exhaust valve is question, i can only depress about 1/2 inch and it hits deadstop. the other valve will go at least twice as far. turning the motor over doesn't seem to affect this.

penetrating oil and a whack from a small hammer and i'm back in business! however it won't continue to run over a minute. i'm sure i messed up the carb when i dissassembled that earlier.

there is no gasket between the bowl and the carb, i ripped that and didn't replace it. no leaks, tho.

Took the bowl off the carb, removed the float and needle, and for the first time I pulled the next piece out, a plastic disk like thing, blasted it good with carb cleaner, and I'm back in business. Just did 2 driveways, a foot of heavy snow, ran good. Thanks for the help! I'm a Happy boy.

mtbmike wrote:
Nice Work!!!... I would recommend u get a gasket for the carb bowl lol..