Sailman 1,291 #1 Posted May 31, 2023 (edited) Looking at an anniversary 520 H with low hours but appears tough cosmetically. Interested to know the pros and cons of this model from owners, the good, the bad, the ugly. Also what things to look for or do on initial inspection other than the obvious knocking, smoking or weak hydro. Bring it on! Thanks! Price range suggestions would be appreciated. Edited May 31, 2023 by Sailman 1 Share this post Link to post Share on other sites
rmaynard 15,436 #2 Posted May 31, 2023 Check to see how it was maintained. We're the engine tins removed and the fins cleaned. Biggest cause of overheating and burning rear valve seat. Also check the nine pin connector for any signs of overheating or burning. Other then that, if the price is right, buy it. 3 Share this post Link to post Share on other sites
lynnmor 7,305 #3 Posted May 31, 2023 You said it looks tough cosmetically, if it wasn’t garaged I would forget about it. You will need to do normal service that requires some disassembly and corroded fasteners can be a significant issue. BTDT 1 Share this post Link to post Share on other sites
Ed Kennell 38,158 #4 Posted May 31, 2023 10 hours ago, rmaynard said: Check to see how it was maintained. We're the engine tins removed and the fins cleaned. Biggest cause of overheating and burning rear valve seat. Also check the nine pin connector for any signs of overheating or burning. Other then that, if the price is right, buy it. I'll add a check of the fuses and the fuse holder for corrosion. The PTO safety switches and holders. Axle seals and hub set screws. The grommet seal around the engine oil filter. BTW, if you have a flexible bore scope tool, you may be able to check the rear cylinder cooling fins by removing the grommet. The one feature I never liked on the later 520Hs is the motion control lever on the steering column. That's why I only keep '88s and '89s. 2 Share this post Link to post Share on other sites
Moparfanforever 844 #5 Posted May 31, 2023 Hard to beat the sound of those big ole' Onan's , but they do like to drink alot of fuel !! 4 Share this post Link to post Share on other sites
rick 233 #6 Posted May 31, 2023 38 minutes ago, Moparfanforever said: Hard to beat the sound of those big ole' Onan's , but they do like to drink alot of fuel !! Amen to that, even the P216 is thirsty. 2 Share this post Link to post Share on other sites
lynnmor 7,305 #7 Posted May 31, 2023 2 hours ago, rick said: Amen to that, even the P216 is thirsty. They are 16 to 20 horsepower flat head engines, it doesn't matter the brand. Flat head engines couldn't meet the emissions requirement so they no longer are produced. Higher emissions from lower compression engines can be expected to be less fuel efficient. Some of us are fine with more fuel consumption if we can have reliable and long lasting engines instead of the more complex disposable newer products. 2 Share this post Link to post Share on other sites
Beap52 811 #8 Posted June 1, 2023 I like the Onan just because I like the old flat heads. My last mower was a Snapper LT12 with a briggs twin. I really liked listening to that little twin exhuast--I didn't care for the mower. It was my father in law's and he bought it new. It was given to us after he died so I ran it till it was wore out. I was given a '94 520H that had been sitting in a barn for ten years. $600 dollars later it was mowing grass. They do like to be fed and I think it takes twice the gas our zero turn does. I suppose my issue is adjusting for grass height. With the hydraulic lift, I don't know how tall I'm cutting the grass. I have put a chain from the frame to the front of the deck so we can't scalp the yard. I really like how easy the 520 steers and like the forward/reverse lever on the dash. It hurts my hip to use foot lever. 1 1 Share this post Link to post Share on other sites
lynnmor 7,305 #9 Posted June 1, 2023 25 minutes ago, Beap52 said: I like the Onan just because I like the old flat heads. My last mower was a Snapper LT12 with a briggs twin. I really liked listening to that little twin exhuast--I didn't care for the mower. It was my father in law's and he bought it new. It was given to us after he died so I ran it till it was wore out. I was given a '94 520H that had been sitting in a barn for ten years. $600 dollars later it was mowing grass. They do like to be fed and I think it takes twice the gas our zero turn does. I suppose my issue is adjusting for grass height. With the hydraulic lift, I don't know how tall I'm cutting the grass. I have put a chain from the frame to the front of the deck so we can't scalp the yard. I really like how easy the 520 steers and like the forward/reverse lever on the dash. It hurts my hip to use foot lever. You don’t adjust mow height with the hydraulic lift, you use the lever for the rear deck wheels. Download the manual for your deck model and do ALL of the adjustments from initial install to the end. 4 1 Share this post Link to post Share on other sites