Daron1965 644 #1 Posted June 3, 2021 I found a 520H in very good shape. Some rust on the deck. 653 hrs. Original tractor with hubcaps. Asking $950 Im not real familier with them. Can you guys please tell me the good and bad? I may make it a garden plow tractor if I get it. What do you think. 2 Share this post Link to post Share on other sites
horseyheaven 112 #2 Posted June 3, 2021 The 520H is a good tractor. I personally like the Onan engines, even though some will say stay away from them. Make sure you listen for any valve train noise like a tic tic sound. I bought one that was running and still ran good. It had a tic sound and after I got it, I found out it was a loose valve seat. That tractor had 1300 hours on it and it was not really well cared for. So, I fixed it with another block that I found that was like new. So, you need to watch out for things like that, but overall, they are good. If you get it, make sure to blow out the cooling fins on the motor after each mowing with compressed air and when grass begins to collect on the flywheel screen when you are mowing, be sure to brush it off. If you maintain these engines and keep them cool, they will run a long time. Another thing that I have done to all of my Onans, (four now) is slot the belt guard on the rear cylinder to help with cooling and air flow. You will also want to make sure the grommet is around the oil filter for optimum cooling. It may not hurt to do a compression check of the engine if the seller is okay with it. I purchased a used Onan engine once that I heard run and it ran great. When I was ready to do the transplant onto another Wheel Horse, I did a compression check to see the condition of the motor before I put it on. Guess what? It was only running on one cylinder because it had a broken rod. The pieces were all laying in the oil pan and it ran great with no vibration or knocking. I was fooled. So, there are many things that can happen. The working hour meter on this tractor was showing 900 hours. I am not telling you this because I want to scare you away, just telling you what happened to me. Compression on my good running Onans is around 120 psi on each cylinder. I do have one with unknown hours that is down to about 90 psi on each bank and it still runs good. As far as the tractor goes, the 520 is rock solid and tough. I use mine year around (one 520H, one 520HC, one 416-8, and one D-160) with mower decks, snow blades, snow blowers, tillers, and front end loaders. The newest 520 I have is 30 years old and it never misses a beat. The parts support is through Toro and most things are still available. However, there are many parts suppliers here Wheelhorsepartsandmore.com and Onanparts.com that carry many things you may need. It it were me, and I were in the market for another garden tractor, I would buy another 520H or HC. Good luck on your decision. Let me know if you have any more questions. 5 Share this post Link to post Share on other sites
tom2p 2,394 #3 Posted June 4, 2021 (edited) well maintained 520 is a great tractor ; this was Wheel Horse top garden tractor for years and many feel it is the 'King' this was a $6K garden tractor (new) 20hp opposed twin Onan produces around 32-33 ft lb torque which few other similar garden tractors will match Eaton 1100 transmission is durable if the tractor was not parked / stored inside - probably a good idea to pass unless the price is too tempting possible / potential issues that can surface include electrical system (wiring harness / connector) - ignition module - and valve seats there is / was (?) a Wheel Horse dealer in your area (Beaver County PA) - Town and Country in Rochester PA ; if they are still there you could stop by and discuss with them Edited June 4, 2021 by tom2p 2 Share this post Link to post Share on other sites
WheelhorseBob 1,549 #4 Posted June 4, 2021 I really like mine. I own two Onan Horses and like them a lot. If abused and not maintained they can be problematic but what isn’t. Onan parts prices are frequently brought up. I will tell you oem for oem they are cheaper than Kohler. I’m rebuilding a k341 Kohler and the prices are horrendous for oem! 1 Share this post Link to post Share on other sites
kpinnc 12,054 #5 Posted June 4, 2021 My two cents- the 520-H is awesome, as has already been said IF it was reasonably maintained. Rust on the deck is normal, unless there are big holes in it. If the deck is a 60, there is almost as much steel in there as a new commercial zero turn. It's nearly bulletproof and probably fixable. If it's a 48, it's still a heavy built deck. Check everything the seller will let you check. Run it, drive it, engage the deck. The Onans are smooth runners and any odd noises should be looked into. At the same time, 600+ hours is alot of residential work time, so it isn't gonna work like a new one. The difference is how much time and money you are willing to spend on it making it perform like new- if that is your intention. If it runs well, it will likely continue to do so for another 1000 hours of you maintain it. 1 Share this post Link to post Share on other sites
squonk 41,118 #6 Posted June 4, 2021 I had one 520. If your good with electric you should be able to keep it running. Pay attention to the bolts that hold the PTO end plate on the engine for loosening up. It happened to me. Lucky for me I noticed it when I just drove the tractor out of the shop so I could sweep the floor. I still had the snowblower and cab on. Lost about a quart of oil in a minute. If that happened when I was snowblowing, it would have blown up! 1 Share this post Link to post Share on other sites
cschannuth 3,816 #7 Posted June 4, 2021 I bought a brand new left over 520 that was still in a crate in 1998 and used it to mow my 3 acres for over 20 years. It received normal maintenance but I did keep it inside the entire time. I never had any issues with it. 1 2 Share this post Link to post Share on other sites
tom2p 2,394 #8 Posted June 4, 2021 8 hours ago, WheelhorseBob said: I really like mine. I own two Onan Horses and like them a lot. If abused and not maintained they can be problematic but what isn’t. Onan parts prices are frequently brought up. I will tell you oem for oem they are cheaper than Kohler. I’m rebuilding a k341 Kohler and the prices are horrendous for oem! many of the comments about Onan parts prices are amusing 520 was a $6K tractor - back in the 90's do you really think a replacement piston will cost $19.99 ? really ? go price a replacement throttle cable from Toro - they are around $67 gimmeabreak 1 Share this post Link to post Share on other sites
JCM 9,166 #9 Posted June 4, 2021 10 hours ago, tom2p said: well maintained 520 is a great tractor Eaton 1100 transmission is durable if the tractor was not parked / stored inside - probably a good idea to pass unless the price is too tempting 2 Share this post Link to post Share on other sites
seuadr 488 #10 Posted June 4, 2021 i have the 520H as my only horse. I bought it with the electrical gremlins and fixed them - it honestly isn't that bad to repair/replace. the only thing that would give me pause looking at one is valve noise or smoking. Even then, i'd consider it if the price was right - a repower isn't that complicated i managed it over the space of a few weekends: Share this post Link to post Share on other sites
kpinnc 12,054 #11 Posted June 4, 2021 9 hours ago, tom2p said: many of the comments about Onan parts prices are amusing 520 was a $6K tractor - back in the 90's do you really think a replacement piston will cost $19.99 ? really ? go price a replacement throttle cable from Toro - they are around $67 gimmeabreak Well some of us could have never been able to afford to own multiple $6000 machines back in the day they were manufactured. I think letting someone know that parts can be expensive is a good thing. For the most part, collecting these tractors can be an inexpensive hobby. But like any hobby, it can also be expensive- all depending on how much we want to spend. With Onan parts, a gasket set can be hundreds of dollars. I think I would like to know that up front. If someone asks for opinions about a tractor that was built over 25 years ago, then they might not know it was expensive then, and can still be today. We all come here for information, and I for one think it is good to include the fact that parts can be expensive. Share this post Link to post Share on other sites
lynnmor 7,306 #12 Posted June 4, 2021 1 hour ago, kpinnc said: With Onan parts, a gasket set can be hundreds of dollars. I see that a complete gasket set can be bought for $142. After-market sets can be had for less, but I don't recommend them. Share this post Link to post Share on other sites
Handy Don 12,231 #13 Posted June 4, 2021 49 minutes ago, lynnmor said: I see that a complete gasket set can be bought for $142. After-market sets can be had for less, but I don't recommend them. And that is a LOT of gaskets to cover two cylinders. Two of just about everything plus a few extra compared to a one-lunger. Without checking, gonna bet that the full OEM quality set for a Kohler twin is not far off that price. Share this post Link to post Share on other sites
WheelhorseBob 1,549 #14 Posted June 5, 2021 11 hours ago, Handy Don said: And that is a LOT of gaskets to cover two cylinders. Two of just about everything plus a few extra compared to a one-lunger. Without checking, gonna bet that the full OEM quality set for a Kohler twin is not far off that price. Probably more and probably no longer available. Sorry I’m a bit frustrated with Kohler right now. Please please don’t tell folks how expensive Onan parts are until you shop Kohler parts. For comparison P220G Onan piston and ring set .020 over is 159.00 and that’s for two pistons with rings. Kohler M20 .020 piston and rings are NLA but the standard piston and rings are available. Only 232.00 bucks for one, so 464.00! Seems Kohler makes all this stuff obsolete and then charges outlandish prices. Btw, I had never looked at Kohler twin parts before just now and I just decided I won’t be buying anything with one in it. And I’m not bashing Kohler, they make fantastic engines. But every discussion about Onan powered horses inevitably turns to Onan parts prices. From my brief search and comparison of similar engines it appears Onan is way ahead in availability and price. 1 Share this post Link to post Share on other sites
onanparts.com 181 #15 Posted June 5, 2021 On 6/3/2021 at 3:25 PM, Daron1965 said: I found a 520H in very good shape. Some rust on the deck. 653 hrs. Original tractor with hubcaps. Asking $950 Im not real familier with them. Can you guys please tell me the good and bad? I may make it a garden plow tractor if I get it. What do you think. At 653 hrs the Onan is barely broke in! An abused Onan will go several thousand+ hours no problem. A properly maintained Onan can easily make it to 3000-4000 hrs. They were designed to be rebuildable. New parts are still made here in the U.S.A. and that is a factor in the cost. Cummins/Onan has not gone offshore. Only a few exceptions are carbs and coils. Made in Japan since the mid 1980's. Everything else made here! They have stood the test of time, many decades.:) The comment about imported aftermarket gaskets is spot on. Avoid them! They are cheap to buy for a reason. Crappy materials. Same goes for any of the garbage Chinese knockoff Onan parts. Failure rate is high. Used Onan parts are out there in the millions! New and NOS, New Old Stock parts, are easy to get. The older Onan's and WH GT's are an investment. They are worth keeping alive. :) Share this post Link to post Share on other sites
EricF 589 #16 Posted June 5, 2021 Another vote of confidence for the 520H and Onan power. One thing to add about things to look out for -- the 9-pin master electrical connector is a well-known source of headaches. Botched or messy fixes by previous owners and so-so repair shops are common. The good news is that there are several sources of replacement OEM-style connectors from vendors here on Red Square -- they're no longer near-unobtainium as they were just a few years ago. The current carried by that connector is at or even above its design limit -- so replacing it is often just a good idea, given its likely age. Like anything else, cleaning up electrical connectors and especially grounds is always good to do, and can save you headaches down the road. Having dealt with RV generators (which use versions of engines in the same families as our tractors) I can say that Onan's parts prices have been getting better and better. Seems like Cummins/Onan has made a commitment to getting stock and prices under control. Kohler is fine until you run into specific parts for a discontinued engine series -- then it's a hunt for an odd part and the whims of market pricing. Standardized Kohler parts that show up across engine models and families that are still in production is no big deal. "It depends," as they say. 1 Share this post Link to post Share on other sites
Daron1965 644 #17 Posted June 6, 2021 Well, I will go and look at later this week. Hopefully it will be as good as described. Owner on vaction until Tuesday. Fingers crossed. Share this post Link to post Share on other sites
Ike 75 #18 Posted June 8, 2021 I like them but hopefully you are good with a volt meter! The carb is easy to take apart to do a quick cleaning and there is a ton of great tech support on this forum. It is my favorite machine. 1 Share this post Link to post Share on other sites