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Discussion Starter #23
So now that summer is here and I have been using the mower frequently, my cub starts good when cold but when it's hot I sometimes experience the same issue as in this video, the starter spins and engages the flywheel but it spins on itself:


Usually I just play with the key to just to turn the engine a little bit and it starts afterwards but why would that be? This is not normal behavior I assume, what could cause this, a cheap replacement starter?


I also checked battery voltage drop when it doesn't start like that and I seen it drop to 7.6volt, so would that mean a bad battery under load or it's just if you but a really big load on it it can drop that low? Because when cold it cranks fine.
 

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Discussion Starter #24
So I just wanted to post an updated I adjusted both valves to .005 and it cranks good as new now, thanks everyone for the help.
 

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Just that rust buildup could have made the gear mesh so tight that it loaded the starter past what it could handle.
 

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Discussion Starter #27
Actually I might of spoke too soon, it cranked real good after adjusting the valves but I still get the occasional hard to turn over when it hits the compression stroke, but it always starts after it gets over the hesitation. In this video I made mutiple start and stop so you can see the behavior. Would anyone know why it would have this kind of behavior? Is. 005 too loose and I should adjust the valves to. 004? I seen another YouTube video where the guy said don't even measure valve clearance with the feeler gauges when adjusting them, just make sure the pushrods turn by hand once tighten down.


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Discussion Starter #28
This is the video I am referring to about adjuting the valves by making sure you can turn the pushrod's by hand once the valve adjustment is tighten down, you can see the poster's remarks in the comments of the video, maybe I will try this:

 

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This is the video I am referring to about adjuting the valves by making sure you can turn the pushrod's by hand once the valve adjustment is tighten down, you can see the poster's remarks in the comments of the video, maybe I will try this:

https://www.youtube.com/watch?v=Y2kY8M8bBEs&lc, Es&lc=UgjKkeo7swmMa3gCoAEC
Once again why I always say everyone on YouTube either does things the wrong way or the hard way. Briggs & Stratton has a set stablished way and it works so why deviate. A lot of people get hung up on the quarter inch or 1/2 inch past top dead center and I often tell them it's not a big deal as long as you go at least that far. You are safe until the Piston gets all the way to the bottom because then the exhaust valve starts to open and you will not be on the base circle of the cam lobe anymore.
The problem is so many auto mechanics are used to setting valves at top dead center or the old school method of turning an engine into 1 valve was fully open and then set the one that was closed. So when one valve spring is depressed you set the one that is not. Unfortunately that is not how these engines work. Cars don't have compression releases are stupid little gimmicks on the camshaft that wear out and cause problems. These do so we must do it the established way we know works. If you would like to set the intake a little on the tight side to make sure you get the most of the compression release is one thing but this guy setting the valves tight on both of them is asking for a burnt exhaust valve or a popped valve seat or slipped valve guide. Valves cool when they are closed. you always want exhaust to be on the loose side if there is no compression release. It is a lot safer than being on the tight side.

Okay, after my rant, I realize we were talking about a Kohler Courage and not a Briggs but the same applies but the same applies you just set at top dead center. I will say there are two different Publications on Kohler literature that has different valve specs. They are closed but not exactly the same. I believe one says 4 to 6 and one says 5 which is right in the middle but still.

Okay, rant number 2. I went to the YouTube page and read the comments at least his comment. If he's using calipers to set it then he's doing it the wrong way anyways. If he use a feeler gauge and set it at. 004-.005 then it should work fine.
Any compression release even if ground into the camshaft will have more effect and work better if the valves are tight or even at zero lash but soon as the engine warms up and things start expanding you won't have proper cooling of valves and you may even have a valve not seal completely and cause a miss which will soon turn into a burnt valve or valve seat. This is not the way to do it.
 

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Discussion Starter #30 (Edited)
Once again why I always say everyone on YouTube either does things the wrong way or the hard way. Briggs & Stratton has a set stablished way and it works so why deviate. A lot of people get hung up on the quarter inch or 1/2 inch past top dead center and I often tell them it's not a big deal as long as you go at least that far. You are safe until the Piston gets all the way to the bottom because then the exhaust valve starts to open and you will not be on the base circle of the cam lobe anymore.
The problem is so many auto mechanics are used to setting valves at top dead center or the old school method of turning an engine into 1 valve was fully open and then set the one that was closed. So when one valve spring is depressed you set the one that is not. Unfortunately that is not how these engines work. Cars don't have compression releases are stupid little gimmicks on the camshaft that wear out and cause problems. These do so we must do it the established way we know works. If you would like to set the intake a little on the tight side to make sure you get the most of the compression release is one thing but this guy setting the valves tight on both of them is asking for a burnt exhaust valve or a popped valve seat or slipped valve guide. Valves cool when they are closed. you always want exhaust to be on the loose side if there is no compression release. It is a lot safer than being on the tight side.

Okay, after my rant, I realize we were talking about a Kohler Courage and not a Briggs but the same applies but the same applies you just set at top dead center. I will say there are two different Publications on Kohler literature that has different valve specs. They are closed but not exactly the same. I believe one says 4 to 6 and one says 5 which is right in the middle but still.

Okay, rant number 2. I went to the YouTube page and read the comments at least his comment. If he's using calipers to set it then he's doing it the wrong way anyways. If he use a feeler gauge and set it at. 004-.005 then it should work fine.
Any compression release even if ground into the camshaft will have more effect and work better if the valves are tight or even at zero lash but soon as the engine warms up and things start expanding you won't have proper cooling of valves and you may even have a valve not seal completely and cause a miss which will soon turn into a burnt valve or valve seat. This is not the way to do it.
Ok well I did try it anyway and it didn't seem to change anything, so I will reset the valve lash to .005. I am still stumped at what my intermittent hard crank could be, it seems it only happens when the engine shuts down near compression stroke(I think). If I kick it for a second with the key and I let go and retry right away it starts right up, but I still think if it should just keep cranking without hesitation just like when it was new. One thing I noticed on both sides, the exhaust valve seat seems to be sitting higher on the head then the intake valve seat, should they be the same? I assume since both sides were like this it was normal but maybe both sides have a problem on the exhaust valve? It's kind of hard to see but I try to put a red square around the area in the picture.

Here is what the behavior is as of now:

Edit:
I just noticed that the intake and exhaust valve stems seals are different on the Kohler parts diagram, so I assume that the exhaust valve being different is normal then.
 

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Ok well I did try it anyway and it didn't seem to change anything, so I will reset the valve lash to .005. I am still stumped at what my intermittent hard crank could be, it seems it only happens when the engine shuts down near compression stroke(I think). If I kick it for a second with the key and I let go and retry right away it starts right up, but I still think if it should just keep cranking without hesitation just like when it was new. One thing I noticed on both sides, the exhaust valve seat seems to be sitting higher on the head then the intake valve seat, should they be the same? I assume since both sides were like this it was normal but maybe both sides have a problem on the exhaust valve? It's kind of hard to see but I try to put a red square around the area in the picture.

Here is what the behavior is as of now:

Edit:


https://youtu.be/QBvfFoYkKLE
That's not the valve seat. That's the valve guide. I was freaking when I read seat and thought WHY IS THIS guy taking the heads off???? Lol
Sorry, I get my panties in a bunch when people do extra or un-needed work.

If they both look the same then probably ok and in factory position but when one slips it usually comes out further and once it is too far....when the rocker goes down...the retainer hits the guide and the pushrod gets bent or sometimes the rocker tears the metal or the stud can bend or pull out or loosen up.

You want to put valve in fully spring compressed position and then make sure you have enough extra leeway room when you push further with your thumb.
If one it too close it will be ok for a while but under ideal conditions or eventually it will pop some or bend a push rod.

You'll know it if this happens so you are fine for now.
I haven't seen a kohler courage yet with a slipped guide. I did one briggs and two Kawasakis last month.

Have you, after valve adjustment, tried a booster pack straight to starter positive stud and ground of case??
Or jumped solenoid with thick wire or pliers or screwdrivers?

You could have some higher resistance anywhere from the ignition switch to a ground cable or battery terminal ends crimped onto cables.

When cranking...and right after a good crank for a few seconds or multiple starts....start feeling around all connections at battery, solenoid etc. Something will be warm to the touch.
 

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Discussion Starter #32
Well I readjusted the valves to .005 and tried to connect the battery positive directly to the starter terminal with a jumper cable with the key in the on position and it still turns hard when it reaches the hard spot. I am starting to wonder, could the engine be hydro-locking? Maybe too much fuel? When it starts it doesn't smoke or anything and runs fine, its only when cranking sometimes that it gets hard to turn. I even tried to turn it by hand when its hard to turn for the starter and its really hard to turn by hand. I guess my engine SV720S has an electronic fuel solenoid on the carb? Maybe that could be it? Maybe ill try cranking it with the plugs out to see if it spits fuel. I don't think the carburetor has ever been off the machine to be cleaned. The spark plugs did look black as if it was running rich when I removed them but when using the mower there was no symptom a part from this hard to start condition.

I dont think it could be a bad electric PTO? If it would be the case I guess I would have issues when I engage it? It seems to work fine when mowing.
 

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So you have bypassed positive to starter now I would try this to check negative cable You might want to establish a new ground by using one half of a jumper cable connect 1 black to negative of battery and other end of black jumper to the engine block. This will give another path for ground and if it then works you know you have a problem with the ground cable connection high resistance


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Anytime you're using jumper cables or a booster pack to test for starting or starting speed or power you should have the negative right on the bottom of the starter or on one of the side bolts that holds it on and the positive on the stud. You want to eliminate every bit of wiring on the entire machine. Otherwise you're not really ruling things out.
 

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Well I readjusted the valves to .005 and tried to connect the battery positive directly to the starter terminal with a jumper cable with the key in the on position and it still turns hard when it reaches the hard spot. I am starting to wonder, could the engine be hydro-locking? Maybe too much fuel? When it starts it doesn't smoke or anything and runs fine, its only when cranking sometimes that it gets hard to turn. I even tried to turn it by hand when its hard to turn for the starter and its really hard to turn by hand. I guess my engine SV720S has an electronic fuel solenoid on the carb? Maybe that could be it? Maybe ill try cranking it with the plugs out to see if it spits fuel. I don't think the carburetor has ever been off the machine to be cleaned. The spark plugs did look black as if it was running rich when I removed them but when using the mower there was no symptom a part from this hard to start condition.

I dont think it could be a bad electric PTO? If it would be the case I guess I would have issues when I engage it? It seems to work fine when mowing.

It's been 6 months since your last post. Did you resolve the issue?
 
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