gldlexglen 1 #1 Posted October 21, 2016 After ~5 minutes of mowing, engine boggs down & loses power. Valves look ok & reset valve tappets. Changed head gasket, new plug, condenser, & points. Engine oil smells ok. Hydro rear axle oil looks & smells ok. Rear axle not overheating. Checked drive belt & pulleys - everything looks normal. Stopping tractor lets engine run ok. Disengaging mower also lets engine run ok. Help! 1 Share this post Link to post Share on other sites
953 nut 51,541 #2 Posted October 22, 2016 Are we talking about an 8 speed, Eaton hydro or Sundstrand hydro? If you disengage the mower while in gear it isn't bogged down? If the mower is engaged while in neutral it isn't bogged down? Share this post Link to post Share on other sites
Sparky-(Admin) 19,457 #3 Posted October 22, 2016 Could it be starving for fuel? Maybe it's time for a new fuel line and in-line filter. Also it's well worth it to replace the fuel shut-off at the tank. Remember that the fuel shut-off at the tank has a mesh filter screen that could be gunked up. Mike..... 2 Share this post Link to post Share on other sites
Don1977 604 #4 Posted October 22, 2016 Could be as simple as the gas cap is not venting. 1 Share this post Link to post Share on other sites
Marv 845 #5 Posted October 22, 2016 I think Sparky and Don are right on. Marvin Share this post Link to post Share on other sites
gldlexglen 1 #6 Posted October 22, 2016 Ok. Thanks for the feedback. I'll get into the fuel filter issues & advise. It's a hydro rear axle, not sure the make. How do I know? What lube is recommended for the hydro rear axle? I've been told everything from 30wt engine oil to 90 wt gear oil. Manuals are void of info. Thanks again. Share this post Link to post Share on other sites
Sparky-(Admin) 19,457 #7 Posted October 22, 2016 If it's a 1980 C-145 it has a Sundstrand Hydro, if it's a late 1980 thru 1984 machine it has the Eaton 1100 Hydro. Neither unit takes 30weight or 90 weight oil. The Eaton uses 10w-30 motor oil, not sure exactly what the Sundstrand uses but I bet it's the same or maybe ATF ( auto trans fluid). Mike..... Share this post Link to post Share on other sites
pfrederi 17,129 #8 Posted October 22, 2016 Hydro filter aimed out the rear Eaton... Filter on right side Sundstrand. Sundstrand could have either ATF or 10w-30. Check the color. Red is ATF Tan 10w-30...DO NOT mix then stick with what ever is in there 1 Share this post Link to post Share on other sites
gldlexglen 1 #9 Posted October 22, 2016 Filter is on left side pointing to the rear - Eaton I take it. It's definitely not ATF. Thanks Share this post Link to post Share on other sites
WH nut 553 #10 Posted October 23, 2016 Could be a plugged muffler Share this post Link to post Share on other sites
gldlexglen 1 #11 Posted October 24, 2016 Replaced entire fuel line, fuel line filter, shutoff valve, cleaned fuel tank, cleaned fuel tank shutoff strainer, and engine still bogs down after ~ 5 min of operation. Gas cap has open vent. Suggestions? Share this post Link to post Share on other sites
953 nut 51,541 #12 Posted October 24, 2016 Presuming you have the battery ignition system it could be the points, condenser or coil. The condenser would be my first suspect, it could give the same symptoms. 1 Share this post Link to post Share on other sites
Howie 882 #13 Posted October 24, 2016 Make sure that condenser is bolted down and grounded good thru the clamp. And if condenser slides out of the holder that it holds the condenser tight. Share this post Link to post Share on other sites
gldlexglen 1 #14 Posted October 24, 2016 Brand new condenser, points, plug, & head gasket. Same problem with old condenser. While mowing, engine boggs down. Releasing the mower clutch allows the engine to recover. Still has a tendency to bog down with hydro running. Suggestions? Share this post Link to post Share on other sites
shallowwatersailor 3,213 #15 Posted October 24, 2016 You weren't clear in your initial posts but have you checked the bottom of your mower deck for buildup of clippings? Pull the deck off and check your spindles, blades, belts, mule drive, and belt tensioner for problems. Without engaging the mower deck, drive around for the amount of time that it usually starts bogging down to see if it still boggs down. 1 Share this post Link to post Share on other sites
gldlexglen 1 #16 Posted October 30, 2016 Engine runs fine with mower deck engaged & tractor parked - I let it run ~30 minutes parked. When mowing engine labors & sputters. If I stop for a few minutes & let the engine recover, I can limp back to the garage. Changed h/s oil & replaced with 10w-30. Let engine cool & drove ~10 minutes without engaging mower & engine bogs down after about 10 minutes. Suggestions? Share this post Link to post Share on other sites
wallfish 15,912 #17 Posted October 30, 2016 While it's "bogging down" try adjusting the choke a little to see if it runs better. If it does run better you have a fuel delivery or air leak problem. If not, then probably an ignition issue. If it's blowing blue smoke while bogging down, it's getting too much fuel. Water in the fuel/carb can also cause that condition or a bad coil. Condenser was already mentioned. A "shakie" connection to a safety switch or a switch itself including the ignition switch could cause that condition too. Plug WIRE???? Best to try and nail down either fuel or ignition as the problem, then go from there. The warmed up engine running rough condition can be one of trickiest things to diagnose a cause. The only other thing from your description is it only seems to be happening when the hydro trans is engaged, warmed up and moving. Not sure if that has anything to do with it or not. 1 Share this post Link to post Share on other sites
shallowwatersailor 3,213 #18 Posted October 30, 2016 2 hours ago, gldlexglen said: Engine runs fine with mower deck engaged & tractor parked - I let it run ~30 minutes parked. When mowing engine labors & sputters. If I stop for a few minutes & let the engine recover, I can limp back to the garage. Changed h/s oil & replaced with 10w-30. Let engine cool & drove ~10 minutes without engaging mower & engine bogs down after about 10 minutes. Suggestions? One other possibility is the governor not adjusting for the load. 1 Share this post Link to post Share on other sites
wallfish 15,912 #19 Posted October 30, 2016 1 minute ago, shallowwatersailor said: One other possibility is the governor not adjusting for the load. HA --Sometimes the completely obvious can escape us. The sailor makes a VERY good point. Set the governor per the manual first. 1 Share this post Link to post Share on other sites
gldlexglen 1 #20 Posted October 31, 2016 Adjusted the governor and same symptoms. Earlier cleaned fuel tank, fuel strainer, all new fuel lines, shutoff valve, & fuel filter. Checked fuel pump as well & seems ok. All electricals are good as far as I can tell. When cold, engine starts normally & sounds normal. As it warms up, I've noticed the engine sound is more "throater", if you know what I mean. It seems to be a "deeper" (lower harmonic) sound. The governor comments by wallfish make sense. What else could be affecting the governor? Any other ideas or suggestions? Thanks! Share this post Link to post Share on other sites
shallowwatersailor 3,213 #21 Posted October 31, 2016 (edited) Three more thoughts/suggestions: Did the tractor have a filter before or is this something added? Is the filter the correct one for the K-Series Kohler? Too restrictive? Too small capacity? The C-145's engine is mounted on a rubber-isolated shaker plate. Is the ground wire intact from the plate to the right rear plate bolt? The grounding wire lugs sometimes break. Is the fuel line routed correctly? Heat causing fuel lock? No kinks either? Edited October 31, 2016 by shallowwatersailor Share this post Link to post Share on other sites
gldlexglen 1 #22 Posted November 1, 2016 Thanks for the feedback sailor. 1. New in line filter is exact replacement of the one I've had on the tractor for years. 2. Shortly after I bought this tractor in 1996 the grounding wire broke. Took awhile to find it then & I learned that lesson. Grounding wire is intact. 3. New fuel line routed same as old & no kinks or restrictions. I'm beginning to think it may be a carb issue or a governor issue just in the way it's running - sound now vs sound earlier. I've always been sensitive to the sound & behavior of machines. The exhaust sound is a lower harmonic & it's running hotter by smell. Any carb or governor suggestions anyone? Thanks! Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,488 #23 Posted November 2, 2016 Could be the muffler. Can you get it off so you can shake it to see if it has a loose baffle inside? That baffle will work it's way to the next baffle and restrict the exhaust port causing the symptoms you describe. Shut it off and the restriction falls away until it works it's way back to the exit. Depends on muffler design but have seen it on the horizontal mufflers on the later 300-Series. Garry 2 Share this post Link to post Share on other sites
woodchuckfarmer 333 #24 Posted November 8, 2016 As an engine warms up things expand. If your valve clearance is to tight the valves will expand( get longer) then you lose compression because they don't seat . After cool down things go back to normal. then it starts all over again Wayne 2 Share this post Link to post Share on other sites
Marv 845 #25 Posted November 8, 2016 On 10/23/2016 at 0:41 PM, WH nut said: Could be a plugged muffler On 11/2/2016 at 6:24 AM, gwest_ca said: Could be the muffler. Can you get it off so you can shake it to see if it has a loose baffle inside? That baffle will work it's way to the next baffle and restrict the exhaust port causing the symptoms you describe. Shut it off and the restriction falls away until it works it's way back to the exit. Depends on muffler design but have seen it on the horizontal mufflers on the later 300-Series. Garry I had this happen on my C141. Very frustrating until I finally figured it out. Marvin Share this post Link to post Share on other sites
