Jump to content
Walhonding520

520h "surging?"

Recommended Posts

ericj    763

for about $ 20.00 you can buy the new parts above and replace them. I replace them most of the time when I get a new to me tractor. especially if it was a non runner.

 

 

 

 

eric j

  • Like 1

Share this post


Link to post
Share on other sites

So the rubber seal on the tank shutoff valve was torn and around the bottom of the screen in the tank. Also, the screen was folded and pinched at the bottom. Am I correct in assuming that this would cause my symptoms? Also, where is best place to buy a new valve and rubber seal?

Share this post


Link to post
Share on other sites
WVHillbilly520H    2,170
1 hour ago, Walhonding520 said:

So the rubber seal on the tank shutoff valve was torn and around the bottom of the screen in the tank. Also, the screen was folded and pinched at the bottom. Am I correct in assuming that this would cause my symptoms? Also, where is best place to buy a new valve and rubber seal?

I'm sure it didn't help with the surging and replacing it after 20+ years should just be part of preventive maintenance, the one I pictured above is on eBay under WH fuel shut off valve, Jeff.

  • Like 1

Share this post


Link to post
Share on other sites

That helped nothing. Surging is actually worse now and I'm running out of options. I might just have to take it to someone with more ability then me.thanks to all who responded at gave suggestions 

Share this post


Link to post
Share on other sites
WVHillbilly520H    2,170

One more little diagnostics tip with it running (warmed up preferred) spray some carb cleaner around the base of the carb and intake manifold, if the rpms speed up then you have carb to manifold gasket ,manifold gasket head leak or worse the 2 piece manifold seal has let go, if the rpms don't speed then not any of the above apply and it only cost you a little more time and a little more carb cleaner, Jeff.

Share this post


Link to post
Share on other sites
WVHillbilly520H    2,170

BTW my Anniversary 520H did this even removing the carb top multiple times for cleaning and changing filter and fuel line to carb, until I removed it completely tore it down and soaked the main body and related metal parts in a can of "Gunk" carb cleaner (Walmart/Advance Auto ect) for a day or two then used compressed air and a can spray carb cleaner through the every orfice I could find/see and installing a new carb and accelerator pump kit before putting it all back together, solved mine but...Jeff.

1460657.jpg

1460658.jpg

Nikki6100AccelPump-springball.jpg

Nikki6100TopOff.jpg

Share this post


Link to post
Share on other sites

I guess I'll try taking it apart and cleaning it one more time. I haven't seen any leaking around the intake. For a while it was running much better so I guess it just plugged up again and needs another cleaning.

I did take the fuel pump apart and it seems clean. Back together and there is plenty of fuel running through the fuel filter.

Share this post


Link to post
Share on other sites
On 7/23/2017 at 8:50 AM, lynnmor said:

Look at the last photo above.  Down near the bottom of the carb you will see a welch plug, make sure it is still there.  I have had one fall out and it gave the same symptoms you described.

 

As always, check the compression first thing.

 

It may be a good idea to just pull the exhaust, intake, carb, and valve covers and do it right.  The exhaust can then be painted, the valves adjusted, the intake checked for sealing and the carb cleaned thoroughly.  Intake gaskets, especially cheap ones, can get sucked in causing similar problems, so use real Onan gaskets there.

The only thing that seemed to cure the surging on my 520h was doing what lynnmor is suggesting. Take the carb completely off the engine, take it apart and soak it overnight, etc. 

Share this post


Link to post
Share on other sites
WVHillbilly520H    2,170
7 hours ago, Walhonding520 said:

I guess I'll try taking it apart and cleaning it one more time. I haven't seen any leaking around the intake. For a while it was running much better so I guess it just plugged up again and needs another cleaning.

I did take the fuel pump apart and it seems clean. Back together and there is plenty of fuel running through the fuel filter.

Those Onan fuel pumps aren't rebuildable and the OE aren't cheap, I get them off eBay 2/$20 cheap insurance when it finally won't pump anymore usually from a pin hole in the diaphragm, Jeff.

Screenshot_20170815-045348.png

Share this post


Link to post
Share on other sites

Thanks. I think I'll get it soaking tonight. I have been doing some searching for a cheaper option of fuel pump. I found a Briggs option but will buy what you have there hillbilly. Will most pumps of that size work anyway?

Share this post


Link to post
Share on other sites
WVHillbilly520H    2,170
35 minutes ago, Walhonding520 said:

Thanks. I think I'll get it soaking tonight. I have been doing some searching for a cheaper option of fuel pump. I found a Briggs option but will buy what you have there hillbilly. Will most pumps of that size work anyway?

Yes, I had one of those "round" Briggs style pumps on mine for quite sometime because I couldn't bring myself to pay $80+ for the OE Onan, then found those and have been pleased so far, Jeff.

Share this post


Link to post
Share on other sites
cleat    1,778

I am using the same ones.

They actually seem to have better check valves than the original one.

 

Just watch and be careful when removing a fuel line from it as they are very brittle and break easily.

 

Cleat

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Recently Browsing   0 members

    No registered users viewing this page.

×