520-H stalling at full throttle

[Posimoto 5]

'88 520-H

My engine was running at full throttle while I was cleaning snow off the cab, engine shut off as if it ran out of fuel. 

Pulled the hose off the bottom of fuel pump that comes from the fuel tank and it was dry besides a bit that trickled out of the pump. 

Connected the hose

The next day,

I pulled the hose off the fuel pump that comes from the tank again and found fuel.

Thinking it may be a dirty fuel cap so I cleaned the cap filter.

Also checked the bottom inlet of fuel pump with a vacuum gauge while cranking and it worked as it should.

I started the engine and it ran fine.

Took it out for snow removal (Ber-Vac blower) this morning and stalled at full throttle several times.

Light snow and only 3"

Each time it stalled, it started right back up without any problems and ran fine until it stalled again.

I decided to run it just off full throttle and the engine seemed to run better without stalling but once.

Fuel filter doesn't have many hours on it but I ordered a new one anyways and will replace it.

Any thoughts on what the problem could be?

 

 

 

 

 

 

 

 

 

 

 

 

[WVHillbilly520H 10,376]

17 minutes ago, Posimoto said:

'88 520-H

My engine was running at full throttle while I was cleaning snow off the cab, engine shut off as if it ran out of fuel. 

Pulled the hose off the bottom of fuel pump that comes from the fuel tank and it was dry besides a bit that trickled out of the pump. 

Connected the hose

The next day,

I pulled the hose off the fuel pump that comes from the tank again and found fuel.

Thinking it may be a dirty fuel cap so I cleaned the cap filter.

Also checked the bottom inlet of fuel pump with a vacuum gauge while cranking and it worked as it should.

I started the engine and it ran fine.

Took it out for snow removal (Ber-Vac blower) this morning and stalled at full throttle several times.

Light snow and only 3"

Each time it stalled, it started right back up without any problems and ran fine until it stalled again.

I decided to run it just off full throttle and the engine seemed to run better without stalling but once.

Fuel filter doesn't have many hours on it but I ordered a new one anyways and will replace it.

Any thoughts on what the problem could be?

 

 

 

 

 

 

 

 

 

 

 

 

The brass strainer in the fuel tank that's part of the petcock/fuel shut could be clogging up or your petcock not all the way open? Do you use ethanol fuel? That's really causes the brass strainer to plug up. Also is your inline filter before or after the fuel pump? If after that shouldn't affect pulling fuel from the tank but pushing it to the carb.

[Posimoto 5]

57 minutes ago, WVHillbilly520H said:

The brass strainer in the fuel tank that's part of the petcock/fuel shut could be clogging up or your petcock not all the way open? Do you use ethanol fuel? That's really causes the brass strainer to plug up. Also is your inline filter before or after the fuel pump? If after that shouldn't affect pulling fuel from the tank but pushing it to the carb.

Thanks for your fast response.

The fuel I use has 10 percent ethanol, nearest ethanol free is over 30 miles, when I'm up that way again I'll grab a few gallons. Fuel filter is after the pump. Petcock is fully open.

I didn't realize there was a brass strainer, I do have a plastic tank.

Would I need to buy something like this?

https://www.ebay.com/itm/302939588596?ul_noapp=true

 

 

Edited February 10, 2021 by Posimoto

[Handy Don 13,129]

That is one version of the petcock. There are others that have a strainer attached to the part that goes up through the bushing into the fuel tank.  Those strainers can clog up, as @WVHillbilly520H noted.

I've even seen them "collapse" inward when clogged as the fuel pump keeps on suckin'

Usually you can see the strainer top of the petcock through the filler cap when the tank is empty, but there is no way I've found to clean it in place . If you remove the petcock, have a new bushing on hand, as an aged one likely will leak if you try to reinstall the petcock through it.

This is and example of one with the strainer: https://www.ebay.com/itm/254668400996?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=254668400996&targetid=1068323854270&device=c&mktype=pla&googleloc=9004198&poi=&campaignid=10459841973&mkgroupid=104612009900&rlsatarget=pla-1068323854270&abcId=2146002&merchantid=137763496&gclid=Cj0KCQiApY6BBhCsARIsAOI_GjajvmagDaQ-VgD_2wVusWhip-VKCTm3r-NYVZouKueQCuViLCRDvWgaAkuDEALw_wcB

[Posimoto 5]

45 minutes ago, Handy Don said:

That is one version of the petcock. There are others that have a strainer attached to the part that goes up through the bushing into the fuel tank.  Those strainers can clog up, as @WVHillbilly520H noted.

I've even seen them "collapse" inward when clogged as the fuel pump keeps on suckin'

Usually you can see the strainer top of the petcock through the filler cap when the tank is empty, but there is no way I've found to clean it in place . If you remove the petcock, have a new bushing on hand, as an aged one likely will leak if you try to reinstall the petcock through it.

This is and example of one with the strainer: https://www.ebay.com/itm/254668400996?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=254668400996&targetid=1068323854270&device=c&mktype=pla&googleloc=9004198&poi=&campaignid=10459841973&mkgroupid=104612009900&rlsatarget=pla-1068323854270&abcId=2146002&merchantid=137763496&gclid=Cj0KCQiApY6BBhCsARIsAOI_GjajvmagDaQ-VgD_2wVusWhip-VKCTm3r-NYVZouKueQCuViLCRDvWgaAkuDEALw_wcB

Thanks for the link and picture. I filled the tank this morning so I'll run it just off full throttle until the tank is near empty then inspect the strainer. I'll post results when I have them.

[lynnmor 7,502]

1 hour ago, Posimoto said:

Thanks for the link and picture. I filled the tank this morning so I'll run it just off full throttle until the tank is near empty then inspect the strainer. I'll post results when I have them.

 

That would be a good time to flush the tank.  While it is a bit difficult, with the two bolts up into the bottom of the tank, it is a good idea to pull the tank regularly to clean out the debris.   If you allow the debris build up, the transmission will run hot and there will be all kinds of rust.

[Handy Don 13,129]

28 minutes ago, lynnmor said:

While it is a bit difficult, with the two bolts up into the bottom of the tank

An understatement if I ever heard one 

Between the tire, the fender pan support, and the oil filter, those little guys are really tucked away. I decided to combine cleaning the tank and an oil change so I'd have the filter off.

[lynnmor 7,502]

1 minute ago, Handy Don said:

An understatement if I ever heard one 

Between the tire, the fender pan support, and the oil filter, those little guys are really tucked away. I decided to combine cleaning the tank and an oil change so I'd have the filter off.

 

I remove the two oil filter mount bolts to get a bit more clearance.  Even waiting for an oil change has you temporarily putting either the oil or new filter on to cover the opening while you clean.  I use Never-Seize on the tank bolts, I don't want to twist out the metal inserts.

[Handy Don 13,129]

4 minutes ago, lynnmor said:

 

I remove the two oil filter mount bolts to get a bit more clearance. 

I looked at that, but on my chassis the hydro lines to and from the filter are metal and I didn't want to chance flexing them.  And yeah, I had to tie a clean rag around the oil filter socket while I worked.

[lynnmor 7,502]

10 minutes ago, Handy Don said:

I looked at that, but on my chassis the hydro lines to and from the filter are metal and I didn't want to chance flexing them.  And yeah, I had to tie a clean rag around the oil filter socket while I worked.

 

The metal lines will flex a bit without damage, even an eighth of an inch is a big help.  I wash down the rear with engine cleaner and a garden hose, so a rag is not enough protection.

[WVHillbilly520H 10,376]

This is what could potentially happen if not cared for properly, bought this 1 used this way. In no particular order...

[Handy Don 13,129]

34 minutes ago, lynnmor said:

I wash down the rear with engine cleaner and a garden hose, so a rag is not enough protection.

For sure if I'd been doing a big clean I would have just put the old oil filter back on temporarily after getting the tank off.

 

17 minutes ago, WVHillbilly520H said:

This is what could potentially happen if not cared for properly, bought this 1 used this way. In no particular order...

    

It is amazing they continue working with this much neglect. Were the transmission fan blades wrecked too? Seat switch overridden and the hydro cam bolt looks maxed (the cam plate seems a bit wallowed out, too.)

Cleaned up real nice in the back there, though!

[WVHillbilly520H 10,376]

12 minutes ago, Handy Don said:

For sure if I'd been doing a big clean I would have just put the old oil filter back on temporarily after getting the tank off.

 

It is amazing they continue working with this much neglect. Were the transmission fan blades wrecked too? Seat switch overridden and the hydro cam bolt looks maxed (the cam plate seems a bit wallowed out, too.)

Cleaned up real nice in the back there, though!

Why the seat switch was bypassed. And to boot this was my old WH dealers personal mower for a while (after trading it on a Dxi not long after I bought my Anniversary 520H) then he just left it sitting after he decided to use a Simplicity ZTR. But he does keep the NOS unsold 522xi in the dry... 

[davedean 2]

What are the chances that the 1/4" vacuum hose is cracked and leaking causing the fuel pump not to perform as necessary. How does one go about getting the flywheel cover off to gain access to that hose? I took all the bolts out that I could find that holds the cover in place and it still wont budge.

Thanks

 

[lynnmor 7,502]

2 minutes ago, davedean said:

What are the chances that the 1/4" vacuum hose is cracked and leaking causing the fuel pump not to perform as necessary. How does one go about getting the flywheel cover off to gain access to that hose? I took all the bolts out that I could find that holds the cover in place and it still wont budge.

Thanks

 

You need to look down around the coil for fasteners, also there are two bolts up from the bottom that can be accessed thru holes in the engine mounting plate.  Even after all fasteners are removed, you need to find just the right movement to get it off.  If you are good at brain surgery, the hose can be replaced with the oil filter and end cover off.

[Handy Don 13,129]

2 hours ago, lynnmor said:

If you are good at brain surgery, the hose can be replaced with the oil filter and end cover off.

  

[davedean 2]

Thanks Handy Don. If you ask me, it is pretty poor engineering as Onan could have used a metal pipe instead of a hose, or offer better access to the hose by way of a trap door in the shroud

 

[lynnmor 7,502]

2 hours ago, davedean said:

Thanks Handy Don. If you ask me, it is pretty poor engineering as Onan could have used a metal pipe instead of a hose, or offer better access to the hose by way of a trap door in the shroud

 

 

It would have been even better if the shroud was separated from the sheet metal at the top so that bolts and whatnot didn't need to be removed there.

[Damien Walker 246]

On 2/11/2021 at 12:35 AM, WVHillbilly520H said:

This is what could potentially happen if not cared for properly, bought this 1 used this way. In no particular order...

 

These pictures are sadly very familiar to me. I purchased a 518H via a famous online auction site and it arrived in a similar state..the deck was completely wrecked due to rust. Following an extensive complete strip down restoration, I finally got to drive it out of the shed for the first time yesterday....and I looked back over my shoulder to see a thick trail of oil running back whence I had come. Oil everywhere. Previous owner never cleaned out the grass cuttings and stored the tractor outside (sacrilege!) and the result was a damp mass of cuttings around the metal filter to transmission return pipe......which had burst due to the rust. Whilst I am great fan of all things Wheelhorse, I have to say that they are not easy to work on...as far as I can see, there is insufficient clearance between the body work and the transmission to allow the nut on the pipe to pass through the available space...ie if seems that you have to split the tractor to change the pipe. For what it is worth, I have a spare pump to lift valve hose and have managed to use that in the meantime. I passed it over the top of the transmission and, ideally it would have been better it a couple of inches shorter but it has kept me going. One final word of warning though is that the back pressure from the hose must be greater than for the original metal pipe. I started up this afternoon and drove out of the shed to an even BIGGER mess....the increased back pressure had blown the oil filter seal out!

 

I'll get a new pipe but if there is anyone out there who has changed this pipe and knows how to do it without seperating chassis and transmission, I'd be grateful to hear your advice!

[Damien Walker 246]

Quick update: the filter to transmission return pipe is no longer available from Toro (though I note there are a few on ebay), so I brazed mine, slipping the trimmed broken ends into a larger piece of steel pipe. Fitting it was a complete @#$%^&!

 

As I have only just put the tractor together, I couldn't face taking it apart again.

 

First problem is that there is insufficient room between the transmission and the centre console to let the nut on the pipe pass between. I made room by chain drilling and taking out a small piece of the rear of the centre console just behind the slot for the brake linkage. I'm not going to photograph it because it is a horrible mess (embarassed) but the nut passes through. With the space available it is difficult to do a more professional job without a significant dismantle. Taking the brake levers off is not easy because it seems you have to get spanners on both sides of the transmission ...which was impossible for me with the number of hands I have and the lack of room in the shed. If you remove the brake band and the long bolt and spring that actuated it, you can winkle the pipe into position. Left rear wheel off of course. 40 mins mowing the lawn this evening and no (noticed) leaks.

[lynnmor 7,502]

If I am thinking of the same pipe, I had one kinked and bought a used replacement from A-Z Tractors.  To make enough room, I loosened the transmission mounting bolts and pried the transmission back.

[Handy Don 13,129]

I concur that the metal tubing for the trans and lift supplies are not readily serviced, but I suspect their "mean time between failures" (when following the well-documented maintenance guidelines) is longer than rubber/fabric hose. And for factory installation, they were probably less costly. JMO

 

[Posimoto 5]

On 2/10/2021 at 1:46 PM, Posimoto said:

'88 520-H

My engine was running at full throttle while I was cleaning snow off the cab, engine shut off as if it ran out of fuel. 

Pulled the hose off the bottom of fuel pump that comes from the fuel tank and it was dry besides a bit that trickled out of the pump. 

Connected the hose

The next day,

I pulled the hose off the fuel pump that comes from the tank again and found fuel.

Thinking it may be a dirty fuel cap so I cleaned the cap filter.

Also checked the bottom inlet of fuel pump with a vacuum gauge while cranking and it worked as it should.

I started the engine and it ran fine.

Took it out for snow removal (Ber-Vac blower) this morning and stalled at full throttle several times.

Light snow and only 3"

Each time it stalled, it started right back up without any problems and ran fine until it stalled again.

I decided to run it just off full throttle and the engine seemed to run better without stalling but once.

Fuel filter doesn't have many hours on it but I ordered a new one anyways and will replace it.

Any thoughts on what the problem could be?

 

 

 

 

 

 

 

 

 

 

 

 

Way late on the response, hope this helps others. I pulled the metal strainer and gave it a good cleaning. After cleaning I re-installed the strainer with a new grommet this fixed my fuel starvation problem.