Bottom right valve cover bolt

[PTmowerMech]

Kohler V twin. Gonna adjust the valves on it because it's not turning over very well. Kind of starts and stops turning over mid stream. The battery is charged fully.

I've had one or two of these break off. It's always the same one. Bottom right. So these two bolts (both cylinders) are tight as all get out. I haven't put anything more than a cheap 1/4 walmart brand impact on them (yet).

So before I go gorilla on it and snap it off, I'm thinking I'd better check with the experts first. I'm thinking maybe run it til it get hot, then cools down?

Anyone know any trick to this? My luck the bolt will break off below the surface.

P.S. I tried tightening and loosening. But that didn't help.

 

[StarTech]

Sometimes you just have to break them off as they are galdded badly from the area heat up so much that it melts the aluminum. Drill out those 6mm screws and tap to M7-1.00 and you be fine. Just a pain to have to it. Just got to the drill bit centered.

 

[PTmowerMech]

Sometimes you just have to break them off as they are galdded badly from the area heat up so much that it melts the aluminum. Drill out those 6mm screws and tap to M7-1.00 and you be fine. Just a pain to have to it. Just got to the drill bit centered.

The two i've done before, I was lucky enough to have a ridge right in the middle of the broken screw. It's a real pain in the rear trying to angle that drill bit back to center.

 

[StarTech]

Try doing it on an engine that turned sideway of normal position even harder. Sometimes you have to pull the engine.

As I said it is a pain to do.

 

[hlw49]

What engine do you have model spec. and serial.

 

[Scrubcadet10]

got a torch? heat it up, and loosen it while it's still hot.

 

[VegetiveSteam]

Kohler V twin. Gonna adjust the valves on it because it's not turning over very well. Kind of starts and stops turning over mid stream. The battery is charged fully.

I've had one or two of these break off. It's always the same one. Bottom right. So these two bolts (both cylinders) are tight as all get out. I haven't put anything more than a cheap 1/4 walmart brand impact on them (yet).

So before I go gorilla on it and snap it off, I'm thinking I'd better check with the experts first. I'm thinking maybe run it til it get hot, then cools down?

Anyone know any trick to this? My luck the bolt will break off below the surface.

P.S. I tried tightening and loosening. But that didn't help.

Don't snap it off yet. Valve clearance is NOT your issue. I'm going to guess you're working on a Courage twin or 7000 series? Improper valve clearance will not cause hard cranking on a Kohler twin. There is no compression release so the engine is always cranking under full compression. Nothing can go wrong with the clearance that would raise compresson. If anything, improper valve clearance could cause lower than normal compression. Check your cable connections for both being loose or dirty. Also those solenoids used by the mower mfg. are not the greatest. A couple of proper voltage tests in the right spots can narrow down any voltage issues.

If this engine is 4 to 6 years old check for a bent starter shaft. That was very common and could cause the condition you are describing.

 

[PTmowerMech]

Kohler Courage Pro27
M# SV840-3012
S# 4003614973

 

[PTmowerMech]

Don't snap it off yet. Valve clearance is NOT your issue. I'm going to guess you're working on a Courage twin or 7000 series? Improper valve clearance will not cause hard cranking on a Kohler twin. There is no compression release so the engine is always cranking under full compression. Nothing can go wrong with the clearance that would raise compresson. If anything, improper valve clearance could cause lower than normal compression. Check your cable connections for both being loose or dirty. Also those solenoids used by the mower mfg. are not the greatest. A couple of proper voltage tests in the right spots can narrow down any voltage issues.

If this engine is 4 to 6 years old check for a bent starter shaft. That was very common and could cause the condition you are describing.

Thanks for that. I should've looked that up. But adjusting the values is pretty easy. Well, that is if you can get to them.

 

[VegetiveSteam]

Yep it is but like you say, if you can get the rocker cover off. And you probably already know but if you do adjust them make sure to loosen the center set screw first while holding the adjusting nut before trying to turn the adjusting nut. If not the nut will likely break in half. Seen it dozens of times. But a 2010 built 840 might have still been using a jam nut and not the center set screw. I just can't remember when Kohler made the change.

If you can, check the voltage at the battery and see what it drops to while cranking when it acts up. Then if your tester leads are long enough, leave the black lead on the negative terminal of the battery and touch the red lead to the starter terminal where the cable connects. Crank the engine and see what the voltage is again when it acts up. If the voltage drop between what you had at the battery and what you had at the starter is less than about 2 or 3 volts check the ground side. Again leaving the black lead on the negative terminal of the battery, touch the red lead to the outside case of the starter. Crank the engine and see if you read any voltage. You should not. You should never read voltage on the ground side. If you do, you have a ground issue. Either a connection issue or bad cable.

If the battery voltage drop in that first test is more than about 2 or 3 volts follow that starter cable back to what I call the starter side of the solenoid and do another voltage test to see what the voltage is while cranking with the issue. If it's the same as what you had at the starter do another test but this time on the battery side of the solenoid. While cranking with or without the issue, the voltages should be pretty much the same from the battery, to and through the solenoid and down at the starter terminal. You're going to loose a few 10ths through the solenoid but if you're dropping volts, like 4 or 5 from one side of the solenoid to the other then you're probably in need of a new solenoid.

You can probably do these voltage tests in about 5 minutes but may need a helper to crank the engine while you're holding test leads.

You may already know all of this but some people are really intimidated by anything electrical. I figure it's never hurts to give more info than less in case someone doesn't know.