leeave96 490 #1 Posted November 1, 2013 I'm scratching my head trying to remember that the frame for the 520H tractors at one time was beefed up to withstand some stress cracking from using the 60 inch deck. What about the frames on the 300 and 400 series? Was the fix applied to those frames too? Is it possible the frames are the same between the 300, 400 and 500 series tractors and any mod to a 500 series frame made it to the other series frames as a result. Thanks! Bill Share this post Link to post Share on other sites
bitten 134 #2 Posted November 2, 2013 The 520 frame I have looks identical to the 310 frame. This 520 frame didnt have the extra holes for the reduction steering so maybe a 520 that came with the reduction steering is different in other ways. Share this post Link to post Share on other sites
sorekiwi 761 #3 Posted November 2, 2013 I've never done a detailed comparison between the two, but if they aren't the same then they are very close. Have you compared part #'s? Share this post Link to post Share on other sites
boovuc 1,090 #4 Posted November 2, 2013 They are the same. If there was any "beefing up" of the frame, it actually wasn't a component of the frame but a plate or a thicker metal without the plate on the mount where the transmission bolts to the frame. (I think some members mentioned that in a few threads over the years). I do know that some members have made plates to reinforce the 4 bolt contact where the two join. Any tractor that has been used to plow, "til" gardens or pull, push "things" should have that contact area looked at to make sure it is tight and solid. Older tractors, (60' & 70's C-series for instance), should have that inspected to make sure it isn't rusting away as it will flex if loose. The 312 the PM had my loader on was actually bent from the loader stresses on that tractor. (And most likely from abuse as the PM told me he lent it out for use by a tenant). Share this post Link to post Share on other sites
AMC RULES 37,196 #5 Posted November 2, 2013 Over the years, I doubt there's much difference in these frames. Here's a 520 trans brace mocked up to a stress cracked 702 frame. Share this post Link to post Share on other sites
sorekiwi 761 #6 Posted November 2, 2013 I've never heard any mention of a factory fix for this, but a fairly common problem on 520's running a 60" deck is frame breakage in the middle (right above the round bar that the pedals/footboards mount to). Share this post Link to post Share on other sites
boovuc 1,090 #7 Posted November 2, 2013 Never heard that before. I'll have to look at mine. Don't know if the previous owners had a 60" mounted on it or not. Good information, SoreKiwi! Share this post Link to post Share on other sites
