jsp_333 268 #1 Posted May 31 I sensed my k-91 was running too fast and put a tach on it and sure enough it was turning 4300 rpm instead of 3600. I loosened off the bushing nut and turned the cross shaft counter clockwise as per service manual. Is it only supposed to move about an 1/8 of a turn? Now the engine will only fire with quick start and as soon as that's exhausted it dies. (I checked the gas levels.) So obviously I've done something I just don't know what. Any help would be appreciated. 1 Share this post Link to post Share on other sites
rmaynard 15,554 #2 Posted May 31 (edited) 4 minutes ago, jsp_333 said: Is it only supposed to move about an 1/8 of a turn? That is correct. When you turned the shaft CCW, was the throttle at the idle position? Edited May 31 by rmaynard 1 Share this post Link to post Share on other sites
jsp_333 268 #3 Posted May 31 I would guess and say not because the engine was off. Doesn't the throttle return to wide open position to start the engine. Share this post Link to post Share on other sites
Achto 27,658 #4 Posted June 1 6 hours ago, jsp_333 said: I sensed my k-91 was running too fast and put a tach on it and sure enough it was turning 4300 rpm instead of 3600. Just an FYI - The K90 spins at 3600RPMs to achieve 3.5hp. The K91 spins at 4000RPMs to achieve 4hp. Really only difference between the engines. As per the manual. You need to hold the governor arm wide open and turn the shaft counter clockwise as far as it will go, then tighten the lock bolt. 1 Share this post Link to post Share on other sites
jsp_333 268 #5 Posted June 1 Thanks Achto, glad you mentioned the lock bolt (aka bushing nut) That one has always baffled me. If I tighten it down the bolt, the speed control disc doesn't rotate so I've got it loose enough to allow the disc to move. Is this the correct set up? Share this post Link to post Share on other sites
Achto 27,658 #6 Posted June 1 1 hour ago, jsp_333 said: If I tighten it down the bolt, the speed control disc doesn't rotate so I've got it loose enough to allow the disc to move. Is this the correct set up? The bolt by the white arrow should have a collar machined on the back of it. This allows the throttle plate to spin on it when it is tight. I have gotten the plate cocked a little not allowing free movement when the bolt is tight To adjust the governor, loosen the bolt by the yellow arrow, clip a small Vise grip on to the governor shaft and turn it counter clock wise. I leave the Vise grip hang to hold the shaft in this position. Move the governor arm "blue arrow" to hold the carburetor wide open. Tighten the bolt by the yellow arrow, remove Vise grip and the governor should be set. 3 1 Share this post Link to post Share on other sites
wallfish 17,051 #7 Posted June 1 1 hour ago, jsp_333 said: Thanks Achto, glad you mentioned the lock bolt (aka bushing nut) That one has always baffled me. If I tighten it down the bolt, the speed control disc doesn't rotate so I've got it loose enough to allow the disc to move. Is this the correct set up? The disk should still rotate with that brass nut locked down. The inside hole of the disk should ride on the shoulder of the brass nut. The throttle cable bracket is what gets pinched in between the brass nut and the block The lock nut Dan was referring to is the bolt and nut on the governor arm, not the brass nut. High rpm is set by the position the throttle cable conduit is locked down at. Share this post Link to post Share on other sites
WHX?? 48,888 #8 Posted June 1 14 minutes ago, Achto said: clip a small Vise grip on to the governor shaft and turn it counter clock wise. I leave the Vise grip hang to hold the shaft in this position. The vice grips weigh just enough to hold the gov shaft/arm against the fly weights when making this adjustment. If the throttle cable moved in the clamp that might have throw you off too. 1 Share this post Link to post Share on other sites
squonk 41,216 #9 Posted June 1 Do you have the throttle cable bracket installed? I've run across a few that were missing and without that bracket, tightening down the nut will cause that speed control ring to bind up. 1 Share this post Link to post Share on other sites
jsp_333 268 #10 Posted June 1 As always thanks to the group for the detailed and specific instructions. Photos with arrows take time and are greatly appreciated. Pictured is my set up. Don't know if it's visable but the "shoulder" of the bushing nut is facing the governor arm instead of the engine. Which would explain my speed control disk issues. I'll get the governor arm off and switch it around. I've pulled out the cross shaft for the photo - should it be all the way in or out or does it move with engine speed/ load? 1 Share this post Link to post Share on other sites
Handy Don 12,325 #11 Posted June 1 4 minutes ago, jsp_333 said: the "shoulder" of the bushing nut is facing the governor arm instead of the engine. Isn’t it amazing that a subtle and easy-to-make oops can really mess up the way something operates? Thanks for the extra picture! Share this post Link to post Share on other sites
jsp_333 268 #12 Posted June 1 Apparently my set-up is "good" No need to turn the bushing nut around. There is a shoulder on both sides. Speed control disc rotating as it should. I'm still going drop so oil between the two. Issue now is governor arm will not take the engine to idle. But Have to go to work for a few hours. 1 Share this post Link to post Share on other sites
wallfish 17,051 #13 Posted June 1 The governor arm needs to be set as described above in Atcho's post. 1 Share this post Link to post Share on other sites
Achto 27,658 #14 Posted June 1 2 hours ago, jsp_333 said: I've pulled out the cross shaft for the photo - should it be all the way in or out or does it move with engine speed/ load? There is a groove in the shaft that should have a snap ring on it. this keeps the shaft from sliding in & out. The groove is shown with the arrow. 2 Share this post Link to post Share on other sites
jsp_333 268 #15 Posted June 2 I am completely at a loss. Spent a few hours yesterday afternoon tinkering and making sure everything was as it should be. Achto thanks for noticing the snap ring. It had in fact worked it's way along the cross shaft to the governor arm. Snap ring back in place - Cross shaft is stable now. However the engine will still only fire on ether. It's behaving like a carb issue. Yes there is gas in the carb bowl. 7 hours ago, wallfish said: High rpm is set by the position the throttle cable conduit is locked down at. Today I'm going to try rotating the throttle bracket (Service manual says counter clockwise to increase speed) so I'm going to start with that I guess. Is there anything else I may have missed. Don't get why a governor adjustment would keep the engine from running. Share this post Link to post Share on other sites
wallfish 17,051 #16 Posted June 2 If it will only fire on spray, that's fuel delivery and the carb. That has absolutely nothing to do with the governor. Old gas, water in the bowl and a carb cleaning Dump all the existing fuel out of it, open the carb bowl and spray it out. You would be able to see if water was in the bowl because it sinks to the bottom and separates. That should get it fired up and running THEN you can mess with the governor or throttle cable if need be. 2 Share this post Link to post Share on other sites
squonk 41,216 #17 Posted June 2 We've all been at "Old gas in the fuel bowl avenue" 2 Share this post Link to post Share on other sites
jsp_333 268 #18 Posted June 2 Thanks All. Actually had 2 k-91's give up. One I was testing on a suburban I just got and the one on the rj. I'll drain all the gas, buy fresh lo ethanol gas and clean out the carb. If it walks like a duck and talks like a duck... Share this post Link to post Share on other sites
wallfish 17,051 #19 Posted June 2 We just worked on one for someone at the engine show. Same exact thing, would fire right off with a squirt but wouldn't start or run without it. Cleaned her up and fresh fuel and it was driving around in no time. There was just a little water in the bowl and possibly old gas. The thing is to eliminate them all and verify fuel is flowing from the tank. 1 Share this post Link to post Share on other sites
jsp_333 268 #20 Posted June 3 Pictures kinda tell the story. Carb bowl with crud in it and I consider myself pretty careful about using decent gas ($13.00 gal.) with stabilizer but lesson learned. She turned over and ran effortlessly. I drained the tank and ran the carb dry and put the rj away waiting for the snow. There's plenty of smart people here - any idea what that gelatinous ooze is in the far left of first photo. Share this post Link to post Share on other sites
wallfish 17,051 #21 Posted June 3 I don't know how that stuff grows in there. Glad you got her going Share this post Link to post Share on other sites