stevasaurus 22,764 #76 Posted July 14, 2021 By contrast, the ACR on the one piece cam keeps the exhaust valve open a touch when cranking until the engine starts and reaches certain RPMs. Thus, you do not have full compression and makes the engine easier to turn over. Share this post Link to post Share on other sites
squonk 41,151 #77 Posted July 14, 2021 Looks like it's going to be fun putting that cam back in without that lobe falling off and lining up the thrust washer. I have a rod to go in the back side to help line things up but it looks like it's going to be a PITA 1 Share this post Link to post Share on other sites
Handy Don 12,235 #78 Posted July 14, 2021 1 minute ago, squonk said: Looks like it's going to be fun putting that cam back in without that lobe falling off and lining up the thrust washer. I have a rod to go in the back side to help line things up but it looks like it's going to be a PITA Would it make sense to "glue" it on with a blob of oil-compatible grease (hey @peter lena) spread inside the lobe cylinder? 1 1 Share this post Link to post Share on other sites
peter lena 8,634 #79 Posted July 14, 2021 @Handy Don, don , that sounds like something that I might try , you would not be using much of it , maybe like an stp type of sticky. would give it a trial stick first if possible , just to show that it will work . tough spot , hope it works for you , pete 1 Share this post Link to post Share on other sites
ebinmaine 67,599 #80 Posted July 14, 2021 Really enjoying the back and forth on this thread, folks. Awesome stuff you all helping Mike and in turn, each other like this. 1 1 1 Share this post Link to post Share on other sites
squonk 41,151 #82 Posted July 14, 2021 Here are the tags on the 2 engines. 1st pic is off of the engine I'm working on. 2nd off of parts engine Share this post Link to post Share on other sites
Stormin 9,981 #83 Posted July 15, 2021 Interesting reading. Definitely one for the tutorial section with some editing. 2 Share this post Link to post Share on other sites
squonk 41,151 #84 Posted July 15, 2021 This morning was measure everything day to see what if anything needed to be done to the block and crank. First the bore: Stock bore dia. is 2.938" with a wear limit of 2.941" I set my micrometer to 2.938" Next I zero my bore gauge using the micrometer so at 2.938" the dial will read 0. This isn't easy to do and taking a pic is even harder Next step in inserting the gauge into the bore at the lower unworn area to confirm the bore is the stock size. The gauge should read 0 (again hard to hold the gauge steady and take a pic but it does measure 0) Now to measure taper the max taper allowed is .003" Each line on the gauge is .0005" You measure the taper 90 deg from the crankshaft which are the thrust sides of the bore. I have 1 line so .0005" of taper so it is in spec. Not to measure out of round. I re-0 the gauge where I measured the taper. Then rotate the gauge 90 degrees. The gauge stayed at 0 indicating I have no out of round. Bore is good so the block needs no machine work besides the valve job. On to the piston: Piston is new It measures 2.9310" across the thrust face. Piston thrust face to bore clearance is.007-.010. I have 2.938" minus 2.931" = .007" so it's in spec. Now the crankshaft. Stock crankshaft measures 1.1811" I measure 1.1870= .0059" difference. I'm chalking that up to an old micrometer and my not so steady hands. I measure no out of round on the crank either. I''m going to check the rod clearance with plastigage Lay a strip of the plasitgage across the journal. Install rod and torque to 200 inch lbs. (17 ft. lbs.) Remove rod and measure how much the plastigage has crushed. Spec is .001-.002. I'm just about dab smack in the middle at .0015" Looks like I'm all set with the block and rotating assembly. This block will go to the machine shop for a valve job. Next step is tearing down the parts motor to see if I can use the cam and governor parts out of that. 5 1 Share this post Link to post Share on other sites
ebinmaine 67,599 #85 Posted July 15, 2021 Looks like good news so far... Share this post Link to post Share on other sites
Stormin 9,981 #86 Posted July 15, 2021 What does the valve job entail, Mike? New valve guides and seats recut? Share this post Link to post Share on other sites
squonk 41,151 #87 Posted July 15, 2021 23 minutes ago, Stormin said: What does the valve job entail, Mike? New valve guides and seats recut? Seats cut along with the valves themselves. 1 Share this post Link to post Share on other sites
squonk 41,151 #88 Posted July 15, 2021 (edited) Took the pan off the parts motor and it's in really good shape. It has the 1 piece cam! But the governor arm is broke on this one to. Think I'm going to try to find the parts needed and keep this motor intact. I think with a couple of odds and ends I can make a serviceable long block out of it. Found this in the pan. 1 piece cam: This is what I need. Governor shaft X 2! Edited July 15, 2021 by squonk 2 2 Share this post Link to post Share on other sites
Handy Don 12,235 #89 Posted July 15, 2021 2 hours ago, squonk said: This morning was measure everything day to see what if anything needed to be done to the block and crank. First the bore: Looks like I'm all set with the block and rotating assembly. This block will go to the machine shop for a valve job. Next step is tearing down the parts motor to see if I can use the cam and governor parts out of that. So that's how it's done! Thanks for the tutorial. 1 Share this post Link to post Share on other sites
Gregor 4,846 #90 Posted July 15, 2021 What's with these broken governor shafts? Are guys getting to aggressive with them, or are they a weak spot in the Kohler engine? I have never run across a bad one in the 4 engines I have done. 1 Share this post Link to post Share on other sites
squonk 41,151 #91 Posted July 15, 2021 Beats me. Never had a broken one before. Share this post Link to post Share on other sites
pfrederi 17,741 #92 Posted July 15, 2021 I had one where the rivet holding the tab was loose. 1 Share this post Link to post Share on other sites
squonk 41,151 #93 Posted July 15, 2021 Looks like the valve rotators are missing from the first engine. Add it to the list. Share this post Link to post Share on other sites
pacer 3,173 #94 Posted July 15, 2021 I had a marginal ..... 10 or 12hp? that the tab had broken. It was a 'clean' break and would fit snugly back under the rivet (course it would'nt stay there) so since the engine was pretty well worn anyway I thought what the heck and put a drop of braze on it ..... worked fine! 1 Share this post Link to post Share on other sites
squonk 41,151 #95 Posted July 15, 2021 I could possibly fix one but the tab is gone on the other one. Wondering if "somebody" didn't hook the throttle cable up to the governor lever directly 2 1 Share this post Link to post Share on other sites
Handy Don 12,235 #96 Posted July 15, 2021 18 minutes ago, squonk said: Wondering if "somebody" didn't hook the throttle cable up to the governor lever directly Hey, I don't want no stinking' governor controlling my engine! 2 Share this post Link to post Share on other sites
ebinmaine 67,599 #97 Posted July 16, 2021 1 hour ago, squonk said: I could possibly fix one but the tab is gone on the other one. Wondering if "somebody" didn't hook the throttle cable up to the governor lever directly I've seen it before. Can't say it would surprise me much. Share this post Link to post Share on other sites
D_Mac 8,621 #98 Posted July 16, 2021 (edited) I might have some parts Mike if I ever get to that 875. You are welcome to them. Just stay away from the Tecumseh !!! Edited July 16, 2021 by D_Mac 1 Share this post Link to post Share on other sites
Tuneup 1,433 #99 Posted July 16, 2021 12 hours ago, squonk said: Wondering if "somebody" didn't hook the throttle cable up to the governor lever directly When you're 16 with a minibike, governors limit your on-road potential... 2 Share this post Link to post Share on other sites
Snoopy11 5,714 #100 Posted July 16, 2021 23 hours ago, squonk said: Spec is .001-.002. I'm just about dab smack in the middle at .0015" Feel like spending some extra $ on a billet rod, while you're there? Don Share this post Link to post Share on other sites