kpinnc 12,016 #26 Posted March 28, 2023 Figured out one more bit of good news: my Mag 10 is in fact using a 12 horse block. It had been so long since I rebuilt it that I couldn't remember if it was a K301 casting or not. Well, it's a K301 block, so it can be rebuilt using a 12 horse sized piston. Due to the original cylinder gouging, I had to go .030 over just to get past it. That greatly limits if I could rebuild the M10 or not. Of course I haven't even opened it up yet. My bore may be ok. So if rebuild is needed- I'll need another crank, and a larger piston. Either way, I do have some options. 2 Share this post Link to post Share on other sites
RED-Z06 2,221 #27 Posted March 28, 2023 45 minutes ago, kpinnc said: Figured out one more bit of good news: my Mag 10 is in fact using a 12 horse block. It had been so long since I rebuilt it that I couldn't remember if it was a K301 casting or not. Well, it's a K301 block, so it can be rebuilt using a 12 horse sized piston. Due to the original cylinder gouging, I had to go .030 over just to get past it. That greatly limits if I could rebuild the M10 or not. Of course I haven't even opened it up yet. My bore may be ok. So if rebuild is needed- I'll need another crank, and a larger piston. Either way, I do have some options. A K241/M10 could be stroked and bored to a K301. The K301 block was used for the M10 and M12 engines as I recall, vs using a separate casting for the M10 and M12. Its my understanding that a K301 could be made into a 14hp K321...i wonder if that rings true here with the M10 using the M12 block..with very thick cylinder walls. http://gardentractorpullingtips.com/engine.htm Share this post Link to post Share on other sites
kpinnc 12,016 #28 Posted March 28, 2023 11 minutes ago, RED-Z06 said: A K241/M10 could be stroked and bored to a K301. The K301 block was used for the M10 and M12 engines as I recall, vs using a separate casting for the M10 and M12. Its my understanding that a K301 could be made into a 14hp K321...i wonder if that rings true here with the M10 using the M12 block..with very thick cylinder walls. Yes, many K241/ M10 engines used the K301/ M12 castings. Since the stroke was determined for 10s and 12s by the throw of the crank mainly, I guess it's possible. The valves would be the clincher for any of these conversions in my opinion. And whether a given machine shop is willing to enlarge the seats and guides. I'll make my way back to the M10 eventually. The Vanguard is working extremely well for now. Guess I'll have some homework to do in the meantime. 1 Share this post Link to post Share on other sites
Bill D 1,920 #29 Posted March 28, 2023 14 minutes ago, kpinnc said: Yes, many K241/ M10 engines used the K301/ M12 castings. Since the stroke was determined for 10s and 12s by the throw of the crank mainly, I guess it's possible. The valves would be the clincher for any of these conversions in my opinion. And whether a given machine shop is willing to enlarge the seats and guides. I'll make my way back to the M10 eventually. The Vanguard is working extremely well for now. Guess I'll have some homework to do in the meantime. I say keep the Vanguard in the tractor. Rebuild the M10/12 and save it for the next tractor that comes along. Share this post Link to post Share on other sites
kpinnc 12,016 #30 Posted March 28, 2023 7 minutes ago, Bill D said: I say keep the Vanguard in the tractor. Rebuild the M10/12 and save it for the next tractor that comes along. Short of a major failure, the Vanguard stays where it is. If, and I do mean if- the Magnum can be rebuilt to a higher HP, then I'll pursue that. More than likely I'll be swapping in a heavy 8-speed to go with the extra power of the Vanguard. This tractor is still my favorite, and now it has none of the limitations that it had before. 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #31 Posted March 28, 2023 6 hours ago, kpinnc said: Yes, many K241/ M10 engines used the K301/ M12 castings. Since the stroke was determined for 10s and 12s by the throw of the crank mainly, I guess it's possible. The valves would be the clincher for any of these conversions in my opinion. And whether a given machine shop is willing to enlarge the seats and guides. I'll make my way back to the M10 eventually. The Vanguard is working extremely well for now. Guess I'll have some homework to do in the meantime. The big change was compression ratio between 10 and 12 and 12 and 14. 6.2, to 6.6 to 7.0:1 respectively. Share this post Link to post Share on other sites
kpinnc 12,016 #32 Posted March 28, 2023 8 hours ago, RED-Z06 said: The big change was compression ratio between 10 and 12 and 12 and 14. 6.2, to 6.6 to 7.0:1 respectively. Yep, definitely gonna have some homework to do on that one... Share this post Link to post Share on other sites
ineedanother 1,369 #33 Posted March 28, 2023 50 minutes ago, kpinnc said: Yep, definitely gonna have some homework to do on that one... I've wondered the same. I have two 10 hps. One M10 and one K241, both k301 castings. I haven't torn either one down but when I do I'll be interested to see how thick the sleeves are. 1 Share this post Link to post Share on other sites
kpinnc 12,016 #34 Posted March 28, 2023 24 minutes ago, ineedanother said: I'll be interested to see how thick the sleeves are. Well one thing is for sure: They can be bored as a minimum to the diameter of a 12 horse piston with no issues. But the cranks are not interchangable. K241/M10s have (I think) a smaller exhaust valve too. So they can be converted as a minimum to 12 horse, but there is alot of machine work involved and quite a few parts to source. ...But it can be done! 1 Share this post Link to post Share on other sites
kpinnc 12,016 #35 Posted April 16, 2023 I know this started as an engine replacement, but since the 310-8 has been a favorite and a dependable machine all these years- she's getting a few more upgrades... Upgraded the 4-pinion tranny to the 8-pinion heavy transmission. New seals, boot, and paint. Added spacers (only one inch, so the deck fits without issues) mainly so it'll have studs. Broke my dang fuel tank grommet. One more thing to fix... Decided to use the "other brand" heavy front axle. I'm out of 520 front ends, so at least I get 1 inch knuckles up front as well. Front and rear track is now 38 inches wide. Giving the wheels fresh paint too, just for the halibut... Got a few little things to finish up, but it should be ready in a day or two. 5 Share this post Link to post Share on other sites
ebinmaine 67,458 #36 Posted April 16, 2023 NIIIIICE 👍👍👍🙂 Share this post Link to post Share on other sites
JCM 9,143 #37 Posted April 16, 2023 On 3/19/2023 at 12:06 PM, Bill D said: Very nice. I love the smooth running twins. 1 Share this post Link to post Share on other sites
JCM 9,143 #38 Posted April 16, 2023 6 hours ago, kpinnc said: Upgraded the 4-pinion tranny to the 8-pinion heavy transmission. I did that as well on my 1989 310-8, nice upgrade Also the red with black spacers and silver/ gray wheels. Sharp 2 Share this post Link to post Share on other sites
Bill D 1,920 #39 Posted April 16, 2023 Could you please share what make/ model the front axle came out of, and what modifications were necessary to install it? Always interested in upgrades. 1 Share this post Link to post Share on other sites
kpinnc 12,016 #40 Posted April 16, 2023 1 hour ago, Bill D said: Could you please share what make/ model the front axle came out of, and what modifications were necessary to install it? Always interested in upgrades. Best I recall was a JD 210. Had to completely redesign the steering tabs. Also had to add almost an inch spacer to make the distance at the pivot pin. Of course then had to fab drag links. Share this post Link to post Share on other sites
kpinnc 12,016 #41 Posted April 16, 2023 (edited) Got the front wheels repainted this morning, and installed them. Also, can't add a new axle upfront without new links... Gonna have to make a new lower steering arm. Tomorrow I guess. Edited April 16, 2023 by kpinnc 2 Share this post Link to post Share on other sites
kpinnc 12,016 #42 Posted April 20, 2023 (edited) Well, the upgrade is done. -New engine. -Newer transmission. -New seat. -New front axle. -New belt and fuel shut off/ grommet. On the front axle I had to use a steel spacer to make the gap of the hanger. I wanted some positive pressure to hold everything together, so I used a 3/4 bolt. I drilled it to accept a cotter pin too. Then I took it for a test drive right at dark. I used a 4 inch transmission pulley, so it's now my fastest horse- definitely better than 10-12 MPH. Not too fast, but a nice upgrade. Now it needs it's annual bath! And I gotta pick a new name for it I guess... No longer a 310-8. More like a 414-8 now. Edited April 20, 2023 by kpinnc 3 Share this post Link to post Share on other sites
ebinmaine 67,458 #43 Posted April 20, 2023 Excellent work sir! Like those V twins. 1 Share this post Link to post Share on other sites
kpinnc 12,016 #44 Posted April 20, 2023 2 hours ago, ebinmaine said: Like those V twins. Me too! I wish recorded audio clearly represents what it sounds like in person. It is so smooth and QUIET. It gurgles like a big engine. I love it! 1 Share this post Link to post Share on other sites
ebinmaine 67,458 #45 Posted April 20, 2023 50 minutes ago, kpinnc said: Me too! I wish recorded audio clearly represents what it sounds like in person. It is so smooth and QUIET. It gurgles like a big engine. I love it! I've seen/heard @AMC RULES machine in person. Excellent fit and finish and function. Share this post Link to post Share on other sites
kpinnc 12,016 #46 Posted April 20, 2023 (edited) On 4/20/2023 at 11:45 AM, ebinmaine said: Excellent fit and finish and function. I have to say I really like these engines so far. Of course the longest I've used one was a couple mowing seasons, so this will be a long term test for certain. I know the carbs are a little finicky, meaning they don't tolerate trashy fuel at all. Any particulate in the float plunger seat causes issues. But otherwise they are the same as Onan Nikki carbs with a smaller throat. Seems the Onans have less issues with such things. I'm just gonna keep a cleaned and ready carb to swap in as needed and run with it. Edited April 26, 2023 by kpinnc 1 Share this post Link to post Share on other sites
ebinmaine 67,458 #47 Posted April 20, 2023 Are you able to get E free gasoline down there? Or as an alternative, a fuel line that will tolerate the alcohol? Share this post Link to post Share on other sites
Bill D 1,920 #48 Posted April 20, 2023 15 hours ago, kpinnc said: Well, the upgrade is done. -New engine. -Newer transmission. -New seat. -New front axle. -New belt and fuel shut off/ grommet. On the front axle I had to use a steel spacer to make the gap of the hanger. I wanted some positive pressure to hold everything together, so I used a 3/4 bolt. I drilled it to accept a cotter pin too. Then I took it for a test drive right at dark. I used a 4 inch transmission pulley, so it's now my fastest horse- definitely better than 10-12 MPH. Not too fast, but a nice upgrade. Now it needs it's annual bath! And I gotta pick a new name for it I guess... No longer a 310-8. More like a 414-8 now. I like the seat. Where did you get it from? Share this post Link to post Share on other sites
kpinnc 12,016 #49 Posted April 20, 2023 (edited) 21 minutes ago, Bill D said: Where did you get it from? They are "seat king" liberators. I actually got this one from Fleabay, and it has a snapper logo on it. Still trying to do something with it, but it was NOS for $75, and new from seat king they are over $200. I have two of them now (first on the 523 below), and they are very comfortable. The open back is nice too. Plastic underside, but very tough. Edited April 20, 2023 by kpinnc 4 Share this post Link to post Share on other sites
kpinnc 12,016 #50 Posted April 26, 2023 On 4/20/2023 at 11:58 AM, ebinmaine said: Are you able to get E free gasoline down there? Dunno how I missed this Eb, but yes I have access to ethanol free fuel. I use nothing else in carbureted engines. 1 Share this post Link to post Share on other sites