Scotts 1642 Kohler CV16S high engine RPMs

[wolf865]

Had an oil leak develop on my Scott's 1642 and the JD service department told my wife it must be the head gasket so to replace it, we did. Discovered there was nothing wrong with the head gasket but replaced it anyway since we had it off. Leak was actually coming from the governor rod, will ask questions about that leak in a different post. Anyway, once we put the engine back together it now runs at a really high RPM! Almost afraid it's going to blow the engine apart. We had mistakenly first set the governor clockwise but then discovered it should have been set counter-clockwise which we corrected but it still runs at the higher RPM. We can adjust it down to a lower RPM for mowing but the throttle is almost 2/3rd below the normal fast position for that. A mechanic told us that having set the governor wrong that a "button" and maybe something else (flyweights?) may have fallen off inside the engine? Can't believe an internal part could come off that easy. So is he blowing smoke? He's recommending that we just go out and buy a new mower as ~$350-$400 isn't worth investing in a 20 year old mower. If his diagnosis isn't the case, what do we need to do to get this back to it's normal RPM while on fast? One unusual thing I've noticed is that the L shaped bar that attaches to the governor rod rocks back and forth anytime it's not on Chock, Fast, or Stop? The spring that's attached to the bottom of it rarely has any tension on it? Don't really see anything unusual about how we slipped the carb back on. Only the 2 metal rods came off of it but they're back where they should be.

 

[hlw49]

open the throttle wide open loosen the clamp bolt on the governor shaft and turn the shaft in the same direction the governor arm traveled holding everything in this position lock it down. Torque the governor lever nut to 88 inch lbs. If this doesn't do it, it has blown the governor inside the engine it only takes one time to over rev. with an improperly set governor to mess it up.

 

[wolf865]

Interestingly enough I was working on the governor rod tonight. That was where my oil leak was coming from so I had to replace the seal (hope that fixed it). Of course that rod will move in/out when you're messing with it. When I was bolting the L bracket back on I suddenly realized that the shaft was rotated almost 80 degrees farther to the left such that the slots on the rod were now pointing more towards the 9 o'clock position whereas before it was more like the 11:30 position. Too late to crank it up tonite but hopefully that could be the problem that was causing the RPMs to be so high?. Any idea what position they should actually be pointing in? The JD dealer didn't flinch when I had told him previously about them being in the 11:30 position. Of course they're also the ones that told me to replace a head gasket that had nothing to do with my oil leak.

 

[wolf865]

We actually managed to mow our yard Thursday by setting the throttle about 2/3rds of the way down toward stop which put the RPMs where they would normally be. Will post what we find when we crank it up in the morning.

 

[wolf865]

And of course... Murphy! Go out there his morning and the mower started fine and the RPMs seemed normal. Pat ourselves on the back. Yaa! Put it in drive but it moved so much slower than it should, didn't die on us though. Came back, loosened the clamp bolt to try what your suggested. Turn the key, click, whiiiiiine! You've got to be kidding us? Solenoid? Just replaced it this spring.

 

[wolf865]

Found the problem with the starter. Somehow there was no right bolt holding the starter on. Who knows when that happened or how long the left bolt had been holding it in place? Was years ago the last time I ever messed with the starter. Anyway, it had finally dropped out of position New bolt from Ace and it starts fine now. Back to the governor issue.
Startled the mower, set the throttle to fast, loosened the bolt on the governor arm, made sure the governor rod was rotated fully counter-clockwise which make the slots on the sides of the rod pretty much parallel to the ground. Manually pushed back the governor arm until the mower sounded like it was at the right RPM before tightening the bolt. When she started driving the mower would only move slowly and the RPMs dropped when she turned on the blades. Tried this several times but never could find a sweet spot where the RPMs, driving speed, and blade engagement all came together. Question, the governor rod will slide in/out of the crankcase. One mechanic told me that there are parts inside the engine that can fall off of the rod is rotated/pushed too far out of position? Any truth to that or was he just looking to do an expensive repair? You would think it would have been designed to prevent that and I have never found anything in my searches that warned against that? If the governor is screwed how is it I can still manually lower the rpms (2/3rd of the way towards stop) in get the mower to where I can at least mow with it (don't want to keep mowing that way though).

 

[wolf865]

Finally decided, what did I have to lose so I tore into the engine to go after the governor rather than spend around $400 or more having someone else try and fix it with no guarantees. That or go out and start looking at a $2000+ replacement mower, though we would have liked a much wider mower deck than the 42" on the Scotts. Taking it off the mower was much easier than expected. Drained the oil, removed the filler tube, marked and unhooked the throttle cable, unplugged a cable connector, took the 2 wires off the starter, unbolted the muffler, removed the pulley assembly from the motor shaft, and removed the four bolts that held it to the frame. Would have been almost perfect if I had only thought to NOT flip the engine in the direction of where the filler tube once was. That was about a 45 minute cleanup! Amazing how much oil is still in that thing after you "drain" it! Removed the 10 bolts and the crankcase and sure enough, there it was, the governor cap and washer sitting in the oil. Crankcase was surprisingly clean, maybe that SeaFoam stuff actually works? The gear was out of position too but that was easily repositioned and there wasn't any damage to it. Reassembled everything, and just as a note, put your gasket material on the part of the case you removed. On first attempt at reassembly I ran a line around the part that was still on the bench but when I went to mate them up there were areas where my line of sealant wasn't up under the cover even though I tried to put my line right down the middle. Also remove the rounded triangle piece on the cover and the 2 little gears there. Had trouble getting the shaft seal to seat properly as I lowered the cover into place but running a thin screwdriver around the its edge helped with that problem. Got the engine back on the frame, everything connected back, refilled the oil (should have done the filter too but...) and crossed my fingers. Runs like a charm though I do think we need to invest in a new muffler! Thanks for the advice and anyone that ever make a Youtube video on the Scotts, they helped immensely and I think I've watched about every last one of them. Just praying the Scott's hold up another 2-5 years until we move to a place with a much smaller yard to mow.

 

[bertsmobile1]

Thanks for getting back
For me it is SOP to fit a new seal as a badly leaking seal can rub the sump empty in no time flat so keep an eagle eye on your oil level ant check the top of the top pulley regularly for oil