520-HC repower

[cafoose 3,354]

I'm thinking of repowering my 1988 520-HC. It runs good I'm just tired of the temperamental and expensive Onan. I would either trade or sell the Onan and I'm thinking of a K-341 16hp. Would that be enough power? I have a 48 inch deck and a 46 inch Ber-Vac snow thrower. I was also checking this thread:

 

 

[ericj 1,578]

call Dale at 610-756-6453 he has some 16 hp tractors that he may trade for your 520-HC if that's the way you want to go

 

 

 

 

eric j

[js5020 111]

I have always heard,,, there is no replacement for displacement.  Your gonna lose 20% of your hp straight away and although I don't remember the numbers exactly your gonna give up quite a bit of displacement going to a K341.  This last snow storm brought 24" to my area and the K341 in the 16 Auto with the 42" single stage didn't want anymore,,, I was crawling as slow as I could to make the first pass, it was tough going.  I have used the blower on a few whimpy 10/12" storms and was able to attain near full speed from the hydro without over working the engine.  I saw a vid of someone who put a K301 in a 520, so it can be done but a blower of that size in deep snow might need all the power that big Onan can put out.

 

Personally I have never had much long term luck with any older twin cylinder air cooled engine. So far so good (7yrs) with the twin cylinder Kawasaki I have in the green and yellow abomination I use to cut the grass though.

 

 

Edited March 23, 2017 by js5020

[Ed Kennell 38,130]

 There's always the HF Predator.

[cafoose 3,354]

1 hour ago, Ed Kennell said:

 There's always the HF Predator.

I thought of that but how reliable would the Predator be? If I did go that route I may be able to sell my Onan and basically get the Predator for free!

 

1 hour ago, ericj said:

call Dale at 610-756-6453 he has some 16 hp tractors that he may trade for your 520-HC if that's the way you want to go

 

 

 

 

eric j

I love my 520 and the Onan when it's running well but it is unpredictable and can be expensive if it breaks I'd rather keep the 520 and repower it if reasonably possible. I have three properties I take care of and a lot of driveway and parking areas when it snows.

1 hour ago, js5020 said:

I have always heard,,, there is no replacement for displacement.  Your gonna lose 20% of your hp straight away and although I don't remember the numbers exactly your gonna give up quite a bit of displacement going to a K341.  This last snow storm brought 24" to my area and the K341 in the 16 Auto with the 42" single stage didn't want anymore,,, I was crawling as slow as I could to make the first pass, it was tough going.  I have used the blower on a few whimpy 10/12" storms and was able to attain near full speed from the hydro without over working the engine.  I saw a vid of someone who put a K301 in a 520, so it can be done but a blower of that size in deep snow might need all the power that big Onan can put out.

Mine has a two stage Ber-Vac would that make a difference?

[WVHillbilly520H 10,373]

I have a complete running low hour (560) 1995 520H with the bagger attachment that I would be willing to part with and has been gone over and fixed on all the trouble spots, and my bought new anniversary 520H (755hrs) has been nearly trouble free for 19 years it's all in how they were cared for before, Jeff.

[js5020 111]

6 hours ago, cafoose said:

I thought of that but how reliable would the Predator be? If I did go that route I may be able to sell my Onan and basically get the Predator for free!

 

I love my 520 and the Onan when it's running well but it is unpredictable and can be expensive if it breaks I'd rather keep the 520 and repower it if reasonably possible. I have three properties I take care of and a lot of driveway and parking areas when it snows.

Mine has a two stage Ber-Vac would that make a difference?

I saw your blower description in the first post, and I think it is where you will really notice the difference in power between the Onan and the Kohler.  Cid specs I found are 47.7 for the Onan and 35.9 for the Kohler, so your certainly giving up displacement and likely the most important part,, torque.  Last time I looked you could buy 2 22hp predators for the price of parts for an Onan rebuild and have a bit left over (I didn't shop around).  I have 2 K series Kohlers and both are very good engines, I'll go as far as saying the best air cooled engines I have ever owned even at 40+ yrs old.  Simple to work on, durable, and when you do need a part nearly everyone has it on the shelf and reasonably priced, unlike the Onan. 

 

There was a recent thread on someone repowering a 175 I believe with a 22 predator and  older threads repowering 520's with 24hp Hondas, and briggs vanguards, might want to do a bit of research on options before running to the smaller K341 and be less than happy with your results.

[ericj 1,578]

If you like the onan, then spend a little bit of money on it and make it more reliable. Unless it is smoking and using oil you may not have to go the rout of an expensive total rebuild. Have you done a compression check on ? you can also do a leak down test. when I have done the leak down test I end up just spinning the motor over. The offer still stands if you want help to check it over.

 

 

 

 

eric j  

[umtg0jn 5]

I have a 1994 520H which is repowered with  a 22HP Predator.   I started the swap in the summer of 2016 after buying the 520H with a seized engine in fall of 2015 for $25 on it's way to the scrap yard.    The predator has a lower crankshaft location which I corrected by raising the engine approximately 1 7/16 inches.  Using a $16 ebay adapter sleeve the original clutch is used. Top of the air cleaner almost touches the hood louvers. The upper bracket bolt holes for the PTO had to be reworked to bolt to the block in the necessary location.  The hard starting disappeared when I went to a 420 CA battery.  I drilled and tapped the upper oil channel to install the factory oil pressure switch which turns on the warning light and runs the hour meter.   It has almost 40 hours now and continues to run great.  I intend to connect the factory tach in the next phase when connecting the vacuum guage.  Looking for a vacuum source that will not affect engine operation.  It handles a 60 inch or 48 inch deck in Bermuda better than my 20 HP Onan.  Power appears better than the 20 HP Onan and more fuel efficient than the 1991 which has been my main tractor for 17 years and has 734 hours.  It is also easier to mow with as it has the improved later style steering.  Also have a 1987 310-8  with 36 inch deck for close mowing.  All have clevis hitches and Ag lug tires for plowing, disking, and blade work.  Use synthetic 10W-30 motor oil in everything, change filters regularly  and expect all these engines to last many years. 

[WVHillbilly520H 10,373]

@umtg0jn, sounds like a success story on the Predator, I have 2 520s my bought new in '98 with 755 hours and a 2cd owner '95 with under 300 hours on it if either 1 decide to hurl a valve seat or piston then the Predator may be a viable option vs a Briggs or Kohler swap, keep us updated on the gauges working with pictures thanks and  to ,Jeff.

[ohiofarmer 3,265]

A word about the predator and the warranty they have. The engine comes with a three month warranty. you can buy a two year warranty to supplement that. What i do is buy the engine and operate it for a couple of months and if all is well, then purchase the two year warranty. The warranty is good for one use only during the two year period which some people do not like, but there is more good than bad in the warranty.

 

 Let's say that the engine lasts two years and two months out of the original 90 day plus two year warranty and then develops oil leak. That leak alone is enough to return the engine and there is no requirement to send the engine somewhere and get it repaired, so you get a brand new one right off the floor. Here is the good part.. Harbor Freight allows you to buy another warranty for another two years, so in essence you could replace the engine every two years for the cost of another warranty.

 

 I bought a 14HP Predator that way and even though the starter wiring failed early on, I just used the manual starter until one week before the warranty expired. They gave me a new one no questions asked and offered me another two year warranty for fifty bucks. That pretty much takes away any worries about quality issues on these engines.

 

 One thing to check on the predator is the air filter. I have seen excellent air filters on some of the small predators, but take the time to see if there is just a cheesey hunk of foam without a proper paper filter on your engine of choice.. That is where they could do better on some of their engines IMHO.

[cschannuth 3,816]

I was sold on the 212cc Predator by my brother. You see, if it can survive my brother and his kids, it can survive anything. I'm very particular and a maintenance freak. He is neither of those things. He bought a small Baja branded Chinese dirt bike from Orschelns Farm and Home 5 or 6 years ago and it had the small Predator. They have run that poor thing to death and it has never had the oil checked or changed in its entire life. It's starts on the first pull every time and is still going strong. 

 

Needless to say, when I came across an almost free 606 roller the Predator was an easy choice for me. It's easily my favorite tractor. I upsized the engine pulley and almost doubled the speed and it handles it with ease. 

 

[umtg0jn 5]

Craig has nice 606.  Re my unique name of "umtg0jn"  . It is a left over from the Air Force.  It is a login code that I have not forgotten so I decided to use it one more time until I can find my old info.   I signed up and joined Red Square forum years ago but could not find my member info in the computer so I started over.   I also need to get one of my granddaughters to help me post some photos.  Dennis, in central Oklahoma