D_Mac 8,593 #5676 Posted July 10, 2020 I have regretted selling a few myself, but I would never ask for them back. Tell him unless he makes you an offer you cant refuse he should start looking for another one. If you decide to sell it in the future he can have first chance at it. 2 Share this post Link to post Share on other sites
Stormin 9,981 #5677 Posted July 10, 2020 Replaced the rubber engine mounts on my C-125, for some nice solid ones that Mickwhitt knocked up for me. 5 1 Share this post Link to post Share on other sites
Stormin 9,981 #5679 Posted July 10, 2020 1 minute ago, Tractorhead said: Not with the state my hands were in. 1 1 Share this post Link to post Share on other sites
Stormin 9,981 #5680 Posted July 10, 2020 Just for you Stefen. 2 1 1 1 Share this post Link to post Share on other sites
johnnymag3 2,515 #5681 Posted July 10, 2020 On 7/8/2020 at 7:40 PM, 8ntruck said: So I found some time to fiddle with the guys M12 with the coil issue??? or not. He has been using my 310-8 so he is in no hurry....but I want this thing out of my garage!!! When I turn the key on, and probe the wire to the top of the coil ...im getting no voltage, yet this thing ran ! Whats going on here? i popped the hood on the other 312 and found power to the positive side of the coil with the key on. One is a K engine, and the other ( his ) is a magnum. Shouldnt there be 12v at that wire when I turn on the key??? Like the other K engine? Share this post Link to post Share on other sites
johnnymag3 2,515 #5682 Posted July 10, 2020 (edited) this is the engine that ran fine for an undetermined amount of time, then snorted, popped coughed.spit fire....then stalled. Starts right back up and runs fine....then if you run it at full throttle its good forever !...anything lower than 1/2 throttle it will start to do its jig/jag whenever....sometimes soon / sometimes later... Gas tank removed and cleaned, carb removed and cleaned, valves adjusted but were not too far out, new gas line, new filter, 3 of them....disconnected fuel line and did a feed with a fuel tank up high for a gravity feed....no fuel pump needed....fuel pumped checked and tested......no problems found and same results every time engine started and tested.....thought coil was bad.....not so sure now./ this no power to it when I turn the key on is a weird thing Took off head to check for carbon issue....nothing, valves seat perfectly Edited July 10, 2020 by johnnymag3 Share this post Link to post Share on other sites
cleat 5,809 #5683 Posted July 10, 2020 The magnum engines use a magneto. That single wire on the coil gets grounded out to stop the spark when you shut the key off. There will be no power measured there. However with the key on it should not be grounded either. A bad coil could be heating up and causing running issues. 2 Share this post Link to post Share on other sites
johnnymag3 2,515 #5684 Posted July 10, 2020 (edited) it is not grounded with the key on, its working as you have just explained..... The question still remains...................why will it run all day at or above half throttle with no issues? It begins its shenanigans under half throttle or idle at an undetermined amount of time....most annoying cleat! I may do the coil anyway...wish I had one to try....oh well, im not using MY Horses parts as Guinea Pigs.... I just tested the white wire to the center of the coil, and it in fact is grounded with the keyoff Edited July 10, 2020 by johnnymag3 Share this post Link to post Share on other sites
pfrederi 17,664 #5685 Posted July 10, 2020 12 minutes ago, johnnymag3 said: it is not grounded with the key off, its working as you have just explained..... The question still remains...................why will it run all day at or above half throttle with no issues? It begins its shenanigans under half throttle or idle at an undetermined amount of time....most annoying cleat! I may do the coil anyway...wish I had one to try....oh well, im not using MY Horses as Guinea Pigs.... The idle circuits have very small passages, You may have to pry out welch plugs to do a thorough cleaning.... Share this post Link to post Share on other sites
johnnymag3 2,515 #5686 Posted July 10, 2020 I did that , and this carb is clean....Marvel run in every gas fill up....amazingly clean. and ran three other carbs on it with the same results. Im so baffled, its something I have never seen before !!! Im still thinking K 12 hp transplant.!!! Been spinning my wheels for months now with this Magnum... I threatened the guy with a motor swap, but he wanted no part of it... Share this post Link to post Share on other sites
ebinmaine 67,274 #5687 Posted July 10, 2020 I'm all for fixing something and doing it the right way. Don't get me wrong here. But you should never have that engine below half throttle anyway except for right before you shut it off. Not something the current owner could just live with? Share this post Link to post Share on other sites
johnnymag3 2,515 #5688 Posted July 10, 2020 Eb.....i tried to talk to him, hes more of a fusspot than me, he is WICKED fussy. He wants it right. Im in the same darn boat now because im into it so much, it baffles me too. I want to find out for me...and he wants to be able to go get the mail at less than full throttle!!! He does mow at 3/4 to full, as the manual states...proper lubrication and all that good stuff. Im grasping for straws here.....the whole thing makes no darn sense 1 Share this post Link to post Share on other sites
D_Mac 8,593 #5689 Posted July 10, 2020 @Stormin hope you had an easier time with changing those mounts then I did. I got 2 on then struggled to the point that I had to walk away and come back next day to finish. Was very pleased with the results. With the rubber mounts at low RPMs the Kohler would shake like crazy. With the solids mounts.... nice and smooth. Share this post Link to post Share on other sites
Tractorhead 9,064 #5690 Posted July 10, 2020 @johnnymag3 This is a strange error what you describe. Ok, Let‘s go again all tests Step by Step. The Engine inside looks pretty Clean and in good condition. Put few dribbs i.eg of dieselOil arround the Valves and check if they closed completely and be tight if piston is on TDC the oil must stay even on the Valvesides without any loss. If that is ok, i would check the Flywheel to Crankshaft connection. pull the Flywheel and check the keeway if it‘s not sheared. if it‘s sheared, the timing goes worse. Complete the Engine again and check it for Compression. do a compression test once with complete cold Engine before any Start once with warm Engine directly after it stalls Values? Did you checked the Choke bowden on carb visualy (Let the chokelever as it is just remove the Airfilter and take a look if choke is completely wide open) next test i would release the magneto shutdown wire from the tractor Harness and isolate it from tractorground try, if the Engine than run‘s in idle, so a possible short of wire harness or any switch can be excluded. Share this post Link to post Share on other sites
ZXT 2,401 #5691 Posted July 10, 2020 59 minutes ago, johnnymag3 said: Eb.....i tried to talk to him, hes more of a fusspot than me, he is WICKED fussy. He wants it right. Im in the same darn boat now because im into it so much, it baffles me too. I want to find out for me...and he wants to be able to go get the mail at less than full throttle!!! He does mow at 3/4 to full, as the manual states...proper lubrication and all that good stuff. Im grasping for straws here.....the whole thing makes no darn sense It's a shame that you don't know anyone with a cellphone. If you did, a video could very easily be taken and uploaded here for us to see what it is doing. After all you've done to it, the only thing left in my mind is the coil. There is a used M16 coil, which is the same as an M12, on ebay for $19.99 + $8 shipping. There is also a seller from China, selling a "kit" with a new coil, voltage regulator, fuel shutoff valve and grommet for $17.92. As cheap as both of those options are, I'd buy one and try it out. I'm not sure what the financial situation is for the guy you're working on it for, but if he won't spend $30 on parts after all of the time you've spent diagnosing it, I'd give him the tractor back and tell him good luck. 2 Share this post Link to post Share on other sites
johnnymag3 2,515 #5692 Posted July 10, 2020 I have a video, it just wont load...or maybe its me... I tried several times Share this post Link to post Share on other sites
ZXT 2,401 #5693 Posted July 10, 2020 Just now, johnnymag3 said: I have a video, it just wont load...or maybe its me... I tried several times Do you have a way to email it? If you do I'd be more than happy to try to get it uploaded for you. Share this post Link to post Share on other sites
19richie66 17,500 #5694 Posted July 10, 2020 (edited) Not my horse but finished up another GT14 tank today. Edited July 10, 2020 by 19richie66 6 10 Share this post Link to post Share on other sites
Tractorhead 9,064 #5695 Posted July 10, 2020 Whooow nice. i like your Tanks 👍 1 Share this post Link to post Share on other sites
Stormin 9,981 #5696 Posted July 10, 2020 40 minutes ago, D_Mac said: @Stormin hope you had an easier time with changing those mounts then I did. I got 2 on then struggled to the point that I had to walk away and come back next day to finish. Was very pleased with the results. With the rubber mounts at low RPMs the Kohler would shake like crazy. With the solids mounts.... nice and smooth. Got to admit, it was a fight. Not run it yet as no starter motor on. Share this post Link to post Share on other sites
johnnymag3 2,515 #5697 Posted July 10, 2020 I have a video, it just wont load...or maybe its me... I tried several times ...here goes again....maybe???? video_of_running_badly.MOV Share this post Link to post Share on other sites
ZXT 2,401 #5698 Posted July 10, 2020 5 minutes ago, 19richie66 said: Not my horse but finished up another GT14 tank today. I saw the pictures on FB earlier and I have to say.... Those are some beautiful welds. 2 Share this post Link to post Share on other sites
johnnymag3 2,515 #5699 Posted July 10, 2020 (edited) video is up....last part shows the breakdown issue and silly nonsense Being a supporter seems to have its benefits !!!! two threads back is video of the angry M12 Edited July 10, 2020 by johnnymag3 1 Share this post Link to post Share on other sites
ZXT 2,401 #5700 Posted July 10, 2020 5 minutes ago, johnnymag3 said: video is up....last part shows the breakdown issue and silly nonsense Being a supporter seems to have its benefits !!!! two threads back is video of the angry M12 Just my opinion, but watching, it looks an awful lot like an ignition issue. 1 Share this post Link to post Share on other sites
