WH 520-H Refresh & Rebuild

[HorseFixer 2,012]

Well what I have here is a Handyman Special, Sometimes things look good in pictures but pictures do not tell the tale of this neglected Tractor. This one is going to need allot of TLC to make it to the level of a dependable machine. Dependable it has to be because It has to fill some pretty big shoes to take over the Job as my Snow Chucker. It has the promise if repaired correctly to Outshine it's predecessor. First off this machine had so much grease, mouse nests, & crud on it that was probably what was holding it together. It ran terrible had wrong plugs, bad wires, dirty carb, rock hard fuel & vacuum lines, and has a couple more possible problems with the engine. The engine will be removed much more cleaning done & then paint. Will need new tires all around, new seat, wiring fixed and just a ton of small fixable things. Here are some pictures of what I started with and then a Video of the Tractor and the engine running. If you guys have any Ideas or suggestions please hit me with them. I'm no expert on Onans and can use all the help I can get. ~Duke

[zieg72 209]

That looks terrible... You can drop it off here and I will responsibly take care of it for you. Actually it looks pretty good IMO. If you need any references I have a 92 and I am about an hour away if you need a look see. These are awesome machines, just cut the grass for the first time with my 96 I recently purchased, just turned 349 hours...

[clintonnut 126]

How many hours?

Probably needs new rings and a bore hone. Mine has 585 hours and it smokes just a tad on a throttle up. Nothing to worry about as all air cooled engines have a little blow-by.

Charlie

[HorseFixer 2,012]

How many hours?

Probably needs new rings and a bore hone. Mine has 585 hours and it smokes just a tad on a throttle up. Nothing to worry about as all air cooled engines have a little blow-by.

Charlie

That looks terrible... You can drop it off here and I will responsibly take care of it for you. Actually it looks pretty good IMO. If you need any references I have a 92 and I am about an hour away if you need a look see. These are awesome machines, just cut the grass for the first time with my 96 I recently purchased, just turned 349 hours...

Charlie there for a minute I thought you were gonna tell me I needed a Clinton. It has 826 hrs on it, and I think a little young for this, but like I said there has been low maintenance. Well I'm gonna do a leak down later today so that may tell the story. I will also take the heads off & Mic The Cylinders I am surprised that a compression test wouldn't show bad rings because both of the cylinders were 130 psi Anyway I hafta spend the first part of the day and clean up the dang garage a bit (prior projects) So's I can MO-TATE around in there. I forgot to mention this in my original post in the Video. I don't know if any of you seen this but Look all the clumps of crap on the driveway That stuff came off the tractor. <_< Will hafta power wash the driveway when I'm done I guess.

Zieg ~Ole pal Ole buddy you need to bring that Low Hr machine to the Dukes Stable So's It can keep this one company!

Guys ~Duke

[118lfd 8]

Duke I hate to bear bad news but the carb will not fix the smoke. On the video it looks like blue smoke. That would mean worn rings or valve guides. A leakdown test will not show if the oils rings or guides are bad, just compression rings. I think you need to go through the motor. Not a bad deal now cause its not terminal it just needs a freshing up. Its probably due to lack of Maintenance. You probably only need to bore and hone it new pistons and rings and new guides. I would go through it now when you have it all apart. That way you can put basically a new motor back on. There was a good thread on an Onan 20 hp rebuild a while back you could follow. Good Luck.

[118lfd 8]

Duke I found a video of your future

[AMC RULES 37,130]

Any progress, how's it coming along? :thumbs2:

[zieg72 209]

Any progress, how's it coming along?

I'd like to say it is keeping my 2 company but he never took me up on my offer... Go figure :banghead:

[HorseFixer 2,012]

Well I am working on the snow cab thingy, and sweeper thingy, The Lights for snowcab thingy, Watching football thingy, I dont even wanna talk about that! Just too damn many thingys going on I Guess! Ill be getting on her Promise. And thanks 118lfd on engine info Im afraid yer right!

~Duke

[HorseFixer 2,012]

I have been busy procuring parts checking the best prices. Not only is this a 520 Refurb it will entail getting into the engine Quite a bit and outfitting it in the battle armor of winter gear to make it my Snow Chucker. It has some pretty big shoes to fill as the C-120 has served me well the last couple years I really have no complaints. Why am I switching? Its the Intimidation FACTOR. Nothing sounds like an ONAN warming up in the morning! eerg errg errg MORE POWER!

Well since I finally got the snow cab mounted to suit me. Overhead Lights and strobe on order for it And some neat clearance lights. this Cab will also be getting a glass Wind Shield And Windshield Wiper System. No need to go out half jacked. Well started tearing into it tonight have the hood and engine out and will take the cab off tomorrow, seat, seat pan, running boards and get that 1" of grease off everything which should take a couple days. Will get new skins all around, chains weights pretty much the full monty. I want to do it right and want it to last me a long time. I have been pricing $$ Parts from ONAN. You don't mess with these big boys without paying the Long Dollar! Anyways here are a few Pics.

[HorseFixer 2,012]

Well to post a few pics of the ones that got deleted, I had quite a bit of clean up to do. Here are some pics of that.

[HorseFixer 2,012]

Over the weekend worked on tearing down and cleaning up the Engine. I will be taking it to my engine Guru doode

and get his opinion on what in needs in order to get my Grocery List together.What it needs is what it will get. After

tomorrow night I will know. Here are some pics of the tear down.

Cheers ~Duke

[AMC RULES 37,130]

Plan to rebuild the motor to stock specs or give it a little oomph in the process?

[KyBlue 655]

Looks like you're off to a good start Duke! That looked to be a pretty nice fab job on the Cab Bracket too

[can whlvr 993]

the motor looks like it came from the shop,not to the shop,she will be nice when refreshed

[HorseFixer 2,012]

the motor looks like it came from the shop,not to the shop,she will be nice when refreshed

Thanks Guys Well got some bad news and good new from my Engine Man Kevin at Pipestone Small Engine. He said Duke the good news is its not a Boat Anchor The bad News is its gonna cost you some MOOOOOLAAAA $$$ Not that Im gonna charge you a bunch its the cost of the Parts $$$ Kevin is very honest and is the best in the buisness and has the Machining Skills and the shop to prove it. Okay this is the deal the cylinders were 10 thousandths out of round and about the same in the cylinder taper The oil control ring had a 100 thousandths Gap! He reccomends .20 over bore, new piston, rings, Standard Rod, New Main Bearings, Gasket Set, He will nurl the valve guides, grind the valves, The labor will cost $250.00 Oh and that includes getting the broke off flywheel bolt outta the crankshaft! Yeah I bucked up! And no SLUGGO WASNT INVOLVED THIS TIME! He says my crank other than the bolt and cam are fine. Anyways that $250.00 is the Cheap part. The parts are about $750.00 which include Connecting Rods, 20 over piston & Rings, Main Bearings, Complete gasket kit, or I can go $ 1079.00 for a complete rebuild kit which includes these additional parts ~ 4 valves, valve locks, valve guides, valve springs, lifters, rodcaps, cam bearings, New Oil Pump, Oil Pump Bypass Spring, Thats an additional $339.00 for those parts would you go that or stay with the $750.00? One thing for sure when its done it will be done right! Ck out his shop below, and tell me which way you would go.

Cheers Broke ~Duke

[Rollerman 290]

Duke how about a Honda or Briggs Vanguard conversion?

[HorseFixer 2,012]

Duke how about a Honda or Briggs Vanguard conversion?

Stephen I'm not that smart! IMHO it wouldnt be a 520...... Yep I'm hard headed. :dunno:

[AMC RULES 37,130]

When someone else is doin' the work the price is never cheap, seems like his labor is very affordable though.

The parts on the other hand, whew! Not so much. If you go with the over bore, you gotta believe it would be one bad mamma jamma once completed.

[dunk50 6]

Duke an old saying comes to mind. Penny rich and pound foolish. The motor is the heart of that machine. $339 over a 10 year period is $33.90 per year for what is essentially a new motor. Bite the bullet and go for it, you only live once. Oh and just as an after thought, how much would a brand new 20 hp Onan cost you if you could buy one?? Bet a heck of a lot more than the rebuild!!

[HorseFixer 2,012]

Let this be a lesson to all of us, When you see a Tractor as Oily, Greasy, as this one was, and ya see a Puff The Magic Blue Smoke Dragon like this one is WALK AWAY! If the machine is filthy then there is a big chance there has been -0- maintenance done on the Machine. No one really knows what they have unless you have prior knowledge and history of the machine. I dont blame the guy I purchased it from cause he never used it, or really ran it much. But the owner before him sent this one to an early grave by not changing the air filter! All engines are a BIG AIR PUMP in essence thats all they are, they suck in tons of air. and this is why the top of the engine is all Bucked up, and not the bottom. Yeah Im doing new Rods, main bearings, ect because I want the engine to outlast me and be trouble free, not because The bottom half is shot to H*ll like the Cylinders are. That being said.....

Will the 520-H Snow Chucker be ready for this winter? Probably not, I was hoping by Jan 1st but these Increased Costs will put a clamp on X-Mas and I dont let these tractors Interfear with my home finances. Too many people do that, and thats one of the reasons why America is in the state it is today. Anyways that will give me time to get everything done but the engine, I still have much to do to get it where it needs to be. Once completed Ill have a Beast that will be familar with that will last me the rest of my life, as it will only be used in the winter. Besides Ole C-120 still blows it into the next ZIPCODE What more could a guy ask for?

Cheers ~Duke

[118lfd 8]

Duke go for all of it. Also make sure he stakes the valve seats. I had a bad feeling when I saw the video. Remember you still have the original chucker and you are not holding yourself to the deadline now. When you are done you will have resurrected an awesome machine and have it for years to come PROBLEM FREE. You will be so much happier when its done, now that you're doing it right. I can't wait to see it throwin snow.

[AMC RULES 37,130]

Also make sure he stakes the valve seats.

I'm not trying to steal your thread, just curious as to what this process involves? Is it vital to keeping these big twins alive long term? Also, is it a simple process that just involves removing the head to do? Thanks so much.

[Curmudgeon 28]

Like Dunk said, it'll be a new engine when you're done, for the cost of a new engine. If you want to stay model correct, it's really your only choice.

Now me, on the other hand, sold the engine off my 520 because of the cost of parts, and am replacing it with a "massaged" Kohler K-532 from a D-200 that was in far worse shape than your 520 when I got it. Of course, once inside the Koher, those parts aren't cheap either, and I don't even have the option of Stens or Primeline to save a few bucks as it seems they never made anything for the big Kohler.

[118lfd 8]

Also make sure he stakes the valve seats.

I'm not trying to steal your thread, just curious as to what this process involves? Is it vital to keeping these big twins alive long term? Also, is it a simple process that just involves removing the head to do? Thanks so much.

It involves peening the material around the exhaust seat with a punch. These motors are notorious for dropping the seats. Mostly cause the rear of the block does not get good airflow from the way they were packaged in the tractor. By peening the area around the seat you effectively pinch the seat so it adds another layer of protection to hold the seat in place. It by no means solves the problem but it does help. I would not rip apart a running motor to do it but while its apart it should be done.

I would punch louvers or drill a series of small holes in the belt cover to add some airflow to that side of the motor. I would also try to keep the fins as clean a possible.