5151 11 #1 Posted September 20, 2023 And my 312h will not start. Oil level is full. What now? Where is the sensor located? Yes, I tried search and manuals. Edit Koehler engine. Share this post Link to post Share on other sites
Pullstart 62,902 #2 Posted September 20, 2023 It seems the sensor is in the oil pan? I’ve heard it can malfunction, but I’ve heard it can be disconnected (or bypassed, I forget if it’s normally open or closed). Share this post Link to post Share on other sites
Lee1977 6,662 #3 Posted September 20, 2023 Just unplug it and see if it starts. If that don't work put a jumper wire on the plug going to the dash. 1 Share this post Link to post Share on other sites
5151 11 #4 Posted September 20, 2023 A guy stopped in just now. Hooked his dewalt jumper to it and fired right up. My battery is only couple months old. Oil light still blinks when I push the test button. Edit, And the volt gauge reads 14 when running. 2 Share this post Link to post Share on other sites
Lee1977 6,662 #5 Posted September 20, 2023 Now check the voltage across the battery with it running should be around 14.5 volts. If not check the voltage coming to the regulator that should me high 30's to 40 volts AC. If you got good AC it's most likly the regulator. Also check all the connections for clean and tight connections .Also check to see if you have a good ground between the engine and frame, I run a extra ground wire between a engine mounting bolt and the battery ground. 1 Share this post Link to post Share on other sites
ri702bill 8,326 #6 Posted September 20, 2023 12 minutes ago, Lee1977 said: Now check the voltage across the battery with it running should be around 14.5 volts. If not check the voltage coming to the regulator that should me high 30's to 40 volts AC. If you got good AC it's most likly the regulator. Also check all the connections for clean and tight connections .Also check to see if you have a good ground between the engine and frame, I run a extra ground wire between a engine mounting bolt and the battery ground. Grounds get corroded over time and stop doing a good job.......... 1 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,046 #7 Posted September 20, 2023 All the oil lights blink and when the test switch is pushed all the lights should come on. That is the bulb test. 1 Share this post Link to post Share on other sites
Handy Don 12,232 #8 Posted September 21, 2023 (edited) 16 hours ago, 5151 said: Oil light still blinks when I push the test button. Blinking oil light is correct when pressing the Test button Gotta read to the bottom before replying! @gwest_ca had you fixed up. Edited September 21, 2023 by Handy Don Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,046 #9 Posted September 21, 2023 If the low oil switch must come out of the oil pan follow these instructions to do so without damaging the switch. There is also a 500 hour service suggested for switch cleaning. 1 Share this post Link to post Share on other sites
5151 11 #10 Posted September 21, 2023 Maybe preforming as it should. Could be a ground or bad batt. I was just through those but will again. And like the extra ground wire comment. Noticed after running the one month old oil seemed milky, on my other tractor a hanging choke plate caused bad rich condition. Going to check that and change oil too. I'll get this thing perfecto yet. Thanks West for that. This tractor has 1000 hrs. Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,046 #11 Posted September 21, 2023 I should add that I have never heard of someone that has serviced the low oil switch so it may not be critical. The magnet needs to be cleaned. Have some oil drain plugs that are magnetic and there is always some iron mud stuck to the magnet on an oil change. The low oil switch magnet should be the same. It is that iron mud that restricts the float switch from operating. 1 Share this post Link to post Share on other sites
5151 11 #12 Posted September 21, 2023 Maybe preforming as it should. Could be a ground or bad batt. I was just through those but will again. And like the extra ground wire comment. Noticed after running the one month old oil seemed milky, on my other tractor a hanging choke plate caused bad rich condition. Going to check that and change oil too. I'll get this thing perfecto yet. Thanks West for that. This tractor has 1000 hrs. When I try to reply this takes me to this reply. Between this and the chickens... Anyways, I checked and the choke butterfly is way choked and the oil is milky. Thanks guys Share this post Link to post Share on other sites
5151 11 #13 Posted October 8, 2023 Well I got it running by disconnecting the oil sensor from the wiring harness. The sensor has no continuity between its two wires. And, with a jumper wire at harness connector, where the sensor wires go, it will not crank. Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,046 #14 Posted October 8, 2023 3 hours ago, 5151 said: The sensor has no continuity between its two wires. That is correct if the oil level is OK. Quote And, with a jumper wire at harness connector, where the sensor wires go, it will not crank. That sounds to be working correctly When the sensor is closed it powers the relay which breaks the power to the starter solenoid. The oil switch is installed in the normally closed (NC) position meaning at rest and no oil the contacts are closed which powers the relay that opens the starter circuit = no start 1 Share this post Link to post Share on other sites