520H charging system

[IthacaJeff 151]

Hi Red Squarers:

I'm looking at a 520H for sale locally with at 60' deck, and the owner claims

it has a charging system problem, and the Onan has 1050 hours. I'm not

at all familiar with Onan engines, so could any of you give me some advice

on what it would take to fix/replace in the worst case scenario? Does the

Onan have 'simple' replaceable alternator? Is this a lot of hours for this

engine?

He's wants $650 . . . I'm inclined to go for it as I'm looking for a mower with

a 60' deck.

Thanks,

Jeff in Ithaca

[Just Piddling 0]

Jeff, I never had a charging issue with my 520, and I can't remember how it worked. Others will be along to help with that.

As far as the Onan's life expectancy, with proper maintenance, they can get a few thousand hours. The biggest issue has been debris clogging the cooling fins causing it to overheat and the valve seats come loose. Check for smoke while running. Anything more than a puff at startup could indicate the problem. Some people have been able to repair the valve seats, but I understand it is kind of hit or miss.

The other biggie is to make sure the hydro is in good shape.

What year is the 520? I assume with the 60" deck, it is 1990 or newer. You see 520s going on ebay for up to $2500, but I think depending on location $1000 - $1800 is more likely. Of course, whatever you are willing to pay is what it is worth.

Good luck

[WheelHorse_of_course 99]

Jeff,

I am speaking generally about outdoor power equipment engines as I have no experience with Onan's.

Unlike a a car the alternator is not a separate component that can be replaced whole cloth.

Normally with this type of engine the flywheel contains magnets and the stator is a series of coils mounted beneath the flywheel.

In the typical engine there are two wires coming from the stator and go to a combination rectifier (AC to DC converter) and voltage regulator. This rectifier/regulator is the most likely cause of problems.

With the engine running you should see an AC voltage across these two wires coming from the stator. With the engine at full operating RPM this voltage should be in excess of 15 volts AC.

If this IS the case it means your problem is the R/VR not the stator or possibly a wring problem. Both of these are relatively easy to fix.

If there is no AC voltage coming from the stator the repair will be more complicated and expensive.

Of course one source of charging problem is that the battery is shot.

Good luck.

:omg:

[Bow_Extreme 550]

The charging system problem is generally related to the wiring in the tractor itself. This issue is especially attributed to the Fuse block located next to the battery. The fuse block, being open to the elements can get wet, dirty, and grimy. This cause a melt down of the fuses and block itself. This is an easy fix. You can replace with a new aftermarket enclosed fuse block or seperate inline fuses. The other problem is the 9 pin wiring harness between the engine and the main wiring harness. Again the connectors are exposed and develop shorts. With a little bit of time and patience, this connector can be replaced. Infact one of the members here on this board sells the new connector for this. If you have a little bit of mechanical apptitude and some experience, these can be easy fixes. I'm not saying that you may not have to dis-assemble the flywheel and make some repairs but again, this is a minor repair. I'd be more willing to bet that the charging system is fine and that the last two issues I mentioned previously are more likely to be the problem. You will also find the wiring at the voltage regulator can become very hot. This is just as easy of a fix. New voltage regulators are available if needed but probably not necessary. I've owned 2 - 520H and each has had it's wiring issues causing problems like you mentioned. Without pics and knowing the condition I can't say if the tractor would be worth the money or not. Personally I would offer in the $500.00 range and save a couple hundred or more to make repairs if needed. Good luck!!

[Bow_Extreme 550]

By the way. If that's Ithaca, MI. I worked there for 3 years and grew up just north of there a ways. Great to have you on the board!!

[IthacaJeff 151]

Hi,

Thanks, gents for the info. I'm not thrilled about diagnosing electrical problems;

it took me a year to finally figure out why my ignition switch on my 310-8 did

not work. . . one of my kids found a fuse lying in the driveway and I noticed that

the fuse had burned (no, the fuse did not blow), which led me to check out the

fuse holder which was fried.

I just rechecked the ad for the 520H and I didn't notice before that a

Kohler is mentioned as the engine. I've emailed the owner to see if that is a

mistake, or could be a replacement. The hood has a Toro label, so it's at least

a 1989/90 or later?

And finally, thanks for the welcome to RS, I'm actually in Ithaca, NY. I've been

a member of the Yahoo WH group, but I like the pics here! One day I may do a

more formal intro on the right pages.

Thanks,

Jeff in Ithaca, NY

[Just Piddling 0]

Hey Jeff, I found the listing you are looking at. http://ithaca.craigslist.org/grd/1120757930.html

The exhaust looks just like mine did. I don't know if it could be mounted to a Kohler.

It is a newer model, with the swept axle, assisted steering, Toro decals and column mounted hydro control.

From the limited view in the pictures, it looks to be in good shape cosmetically.

Bow Extreme is right about the fuse block, I had several issues with mine.

Good luck :omg:

[Olratlr 25]

Don't hardly see how you could go wrong at that price considering what I gave for mine new in

1996. Good Luck.

[hodge 6]

You might be able to whittle the price down, but even at what it is, it should be a fair deal. The 60" deck and a few more parts would bring more than the asking price...

[Buzz 502]

If you didn't buy it someone else did Listing has been deleted by author.