my machine is in a carpet cleaning van. drives a pump and blower. changed out the left head. motor has never run better, but it disburses an occasional cloud of oily smoke. went back to the fellow that changed it out and he replaced the gasket. still puffing out oil. it winds up on the floor of the van, and kind of a lot of oil.
the unit is a kohler commander 20. probably at least 10 years old. i bought it used so i am unsure or how old it is. when it was replaced there was a clearly evident divot in the outside edge of the old one. does not appear to be a crack in the cover.
any comments will be deeply appreciated.
#2
reynoldston
Just where is this oily smoke coming from? Crankcase vent, exhaust, around valve cover??? It sound like it may have too much crankcase pressure, worn out rings and cylinder walls? Bad head gasket? The best test for here would be a leak down test.
Just where is this oily smoke coming from? Crankcase vent, exhaust, around valve cover??? It sound like it may have too much crankcase pressure, worn out rings and cylinder walls? Bad head gasket? The best test for here would be a leak down test.
it is coming from the valve cover. he replaced the gasket and it still smokes. not a steady smoke, but a puff or two every few seconds. burns off on the exhaust and the rest goes on the floor.
it is coming from the valve cover. he replaced the gasket and it still smokes. not a steady smoke, but a puff or two every few seconds. burns off on the exhaust and the rest goes on the floor.
So as I understand the valve cover is leaking oil. The valve cover gaskets has been changed but still leaks. Who ever he is, he isn't doing something right? Warped valve cover? not getting gasket in place right? I also recall that engine has a crankcase breather tube coming out of its right valve cover. Which side are you having the problem. Could it be leaking out the breather tube grommet?
So as I understand the valve cover is leaking oil. The valve cover gaskets has been changed but still leaks. Who ever he is, he isn't doing something right? Warped valve cover? not getting gasket in place right? I also recall that engine has a crankcase breather tube coming out of its right valve cover. Which side are you having the problem. Could it be leaking out the breather tube grommet?
thanks for the comment. he replaced the head on the left. the motor runs way better but it did not have the smoke before the repair. the valve cover is leaking oil. this is correct. looked for cracks. replaced the gasket but it still has a puff of smoke.
#6
reynoldston
Just what model Kohler you have, CV641 or CH640? The valve cover should be made of plastic with special bolts that hold the valve cover down. By chance did HE break off one of these special bolts? and used something else in its place?
Just what model Kohler you have, CV641 or CH640? The valve cover should be made of plastic with special bolts that hold the valve cover down. By chance did HE break off one of these special bolts? and used something else in its place?
ch640. i will check on the bolts. looked at the covers today and could feel air coming out of both of them. more on the left one that is leaking of course. i will check with hims bout the bolts. thank you very much for the help. deeply grateful. will comment when i s/w him.
Maybe...warped cover cannot really be used by pulling down with hold -down bolts. Place the covers on a flat surface and look for light bands or use feeler gauges. Although plastics have improved they usually warp from time/heat. If you have an infra red temp gun take a couple readings on the head away from exh flange/ pipe. (Intek is as hot as 305 F at the spark plug-beware of higher temps). Not familiar with your engine, but only a mist comes up the pushrod tunnels on my Intek to lube the valve stems. That "mist " should not be smoky. As above check for excess crankcase pressure due to "blowby." :2cents:
Anytime a cylinder head is reworked or replaced with new one, the fresh valve job will put and extra burden on the piston rings causing excessive blowby and oil consumption. Its a gambel when ever this is done with out total rebuild. It does however sound like your problem is in the valve cover area.
The plastic valve cover with center bolt has got to be the worst Kohler engine ever made. I have seen these poor oil while still in warranty, Kohler has lost a boat load of these engines from lack of oil. When you re-seal it you have lay a thin bead of RTV high temp on the gasket seal. This is the best fix so far, tighten the bolt as tight as possible and check the covers often, they like leak after cool down. I have seen these poor oil in less than 200 hrs. These engines will also miss and smoke when cutting on the side of hill. Kohlers fix for this was to design a dipstick with a lower full mark, which means theres less oil in the engine causing even more problems.
