522xi / GT22 engine won't keep running

[Vermonty 0]

This one has got me stumped, hoping to find a little help.

 

I've got a New Holland GT22a (aka Toro 522xi) that's been running strong for years.  Last season I was experiencing an occasional loss of power when mowing.  At the very end of the season, I put the tractor away for the winter with the impression that I had an issue with the fuel filter or fuel pump. 

 

This spring, I did some debugging and determined that the fuel pump wasn't delivering fuel to the carb.  I replaced the fuel pump and confirmed that the carb was getting fuel.  

 

The engine will fire and run for a few minutes.  It will then start skipping a bit and die.  If I get it in gear and try to drive, it will die.  I can get it started a few times with this behavior, then it don't start again (flooded?) until it sits for a while.  

 

I was checking the spark plugs, the left spark plug was sparking well as was the right (exhaust side)--however, I noted it was odd that when cranking the engine, I would get shocked when holding the right spark plug boot when it wasn't screwed in.  (???)  Not true when holding the left plug.  Could this be a clue?

 

I just resurrected another 522xi as my "backup" mower, but I'd love to get this one operational again.  Any ideas on what to check next?

[JoeM 7,874]

A few things come to mind.

 

Fuel System Issues. (this is what I found of these machines)

Debris in carb. the top of the carb can be taken off on the machine and the bowl compartment cleaned out with spray and compressed air. 

Debris in the tank. The fuel tank at the outlet gets. Blowing some air back into the tank with the cap off will clear the stuff, test run and if the problem clears and comes back later going to have to remove the seat pan and clean out the tank. You can get to the port through the fuel gauge port on the top of the tank. 

The carb has an electric fuel shut off that must have power to open. they use it as an anti back fire valve. Make sure it is working (should be done when cleaning carb)

 

Ignition

Question, if your machine has a black box on top of the right side near the valve cover it has spark advance.  need to get a couple of those cheap inline spark testers and fire it up and compare the spark intensity. There is a vid on my YouTube channel showing good and intermittent spark. The spark advance if awesome when working and lasts a long time. but the parts are expensive if you can find them. Mostly the coils go bad. There is a kit from Kohler to make the machine a straight mag set up, but you have to pull the engine to install. 

 

 

Edited July 24, 2023 by JoeM

[Vermonty 0]

14 hours ago, JoeM said:

A few things come to mind.

 

Fuel System Issues. (this is what I found of these machines)

Debris in carb. the top of the carb can be taken off on the machine and the bowl compartment cleaned out with spray and compressed air. 

Debris in the tank. The fuel tank at the outlet gets. Blowing some air back into the tank with the cap off will clear the stuff, test run and if the problem clears and comes back later going to have to remove the seat pan and clean out the tank. You can get to the port through the fuel gauge port on the top of the tank. 

The carb has an electric fuel shut off that must have power to open. they use it as an anti back fire valve. Make sure it is working (should be done when cleaning carb)

 

Thanks, this is something that I can check pretty easily in the next day or so.  I had hoped to remove and clean the carb, but got cold feet after seeing how deeply embedded it is.  I can handle a "take the top off and spray it out", though.  

 

When you mention the electric fuel shut off--is there anything specific I'm looking for to confirm that it is operational, or just the appropriate voltage at the terminal?

 

Thank you for the tips!

[JoeM 7,874]

In the back of the carb there is a solenoid with I believe a red wire going to it. If you are somewhere quiet, listen carefully when turning the key to on, should hear a click.  

 

Edited July 25, 2023 by JoeM

[Vermonty 0]

Ok, some things to report.

 

Day1: 

Inline Spark plug tester ordered, but not in hand.

• I got the carb top off and cleaned out the bowl.  There was little sediment there, but quite a bit of fuel pooled up (picture attached).
• I was able to hear an audible 'click' when moving the ignition to the run position, but it was darn near impossible to tell exactly where it was coming from.  All wiring looked to be connected and with clean contacts.  
• Next step was blowing out the fuel line.  I did that from the intake to the fuel filter and blew compressed air through.  
• Changed the battery for good measure.

Got it all back together and cranked the engine.  It was turning over but didn't start up.  I took the air filter off and could see fuel squirting into the carb when choked.  I gave up for the day.

 

Day2:

Spark tester arrives!

• I put the tester on the non-exhaust side and cranked the engine.  Just got the solenoid click sound and couldn't get it to turn over at all.  First thought was that the battery must have been drained?
• A few hours later, I went out again to jump start the mower.  Before changing anything, I put my hand on the seat to activate the switch and turned the key.  It fired right up at the "no choke" position and ran strong for ~1 minute from low throttle to high throttle.  It then struggled/slowed a bit, lost power, and died.  While running, the inline spark tester was showing good spark.
• I switched position of the spark tester to the exhaust side, cranked the engine.  It was lighting up, but alas no more engine running.  Strong smell of gasoline (at least stronger than I remember in the past).  

 

The fact that the mower fired right up with no choke the second time has me wondering.  That's never been the case in the past 15 years (always needed some choke from a cold start).  Having it run for ~1 minute and die is the best I've gotten out of the 5 or 6 starts I've had since the changing the fuel pump.

 

Might it be a bad fuel pump?

 

 

[2kflhr 12]

I have a '97 522xi that is now my back up mower. When it was my primary after after about 15 minutes of runtime it would lose power. I was determined it was a fuel related issue so I changed the fuel pump and etc. It turned out to be one of the coils was bad. I assumed once it got heated up the winding was opening. I replaced both coils and problem solved. I had to remove the body to get to them it though. I found the service manuals on line which was a big help..

[Vermonty 0]

Thanks for the tip.

 

"remove the body" has me a little worried, though.  Is there a way to test these prior to disassembly?  What was involved in getting to the coils?  

 

(I have a donor parts machine, so swapping parts in is a possibility.)