[rwairforce]

Well I seemingly got the carb problem fixed with the lean running. After a float adjustment and a new shaft, etc it seems to run like a Kohler 14 should.
New unknown symptom......
It will run and run while sitting with the throttle at full and mower engaged. Change the throttle and it responds without a hesitation. From idle to full, no problem....now for the ???????????
I drive it around and shortly it starts to slow and sounds like something is binding the motor, or overloading it...the deck is not engaged and remember, when it was sitting still the deck would run with no problem or slowing of the engine. With the engine starting to strain as if it were pulling a tree stump I pull the motion lever to neutral and the engine recovers. I move the lever to forward and within seconds it starts to bog again.....Any ideas?
Please remember that the engine and deck performed well while sitting still. Could I have a bad valve??? or whatever controls forward motion.

Thanks again.

 

[castoff]

Does this tractor have a holding valve?

 

[rwairforce]

I was told it did but I just went out and looked under it and it does have that brick looking piece that you've pointed out in other pictures calling it that very thing. So with the authority we all have vested in you, Castoff, I will say that it does. Please tell me that means something regarding my problem....but tell me that it's cheap to fix.

 

[bhildret]

What RPM is the engine running at? I've encountered some running way over RPM and they can't make enough power there to keep up with the hydraulic pump and pressure at those speeds ...

Should be capped right around 3600 ...

Brian

 

[rwairforce]

Oh lordy, how would one go about determing that number without a tach?
I've seen them on cars but never on a tractor.

So you're saying that if I reduce the engine speed it might indicate that either my engine is running to fast or the pump is going bad?

 

[castoff]

There have been instances where a tiny piece of crap finds its way into one of the pilot valves in the holding valve and creates mayhem. The fact that these tractors do not have an oil filter on the hydraulic system makes this sort of problem a lot more possible than if a filter was present.

Here's the bad part....

The easiest way to diagnose this problem is to remove the holding valve from the tractor and install a set of standard hydraulic lines between the motor and the travel valve. The cheapest way to do that is to tell us the model and serial number of your tractor. Perhaps Ken or Boomer have a pair of lines kicking around that they'd sell you.

If someone else has a different theory, then we both hope that they speak up. I could be wrong. I'm not there to actually see, hear, feel etc what's going on. All it takes is a speck of dirt and if you have a rear PTO, then it's sooooooooooo easy to introduce many such specks into your hydraulic system if you are not careful.

 

[rwairforce]

Thanks, no rear pto.. I have a model 444 serial 14072665.

 

[rwairforce]

Castoff...
Is there a method for flushing this system? Sort of like how we used to flush a heater core by connecting an external hose and flushing it with water both directions.

 

[castoff]

Keep in mind that we use motor oil in the hydraulic system and the motor oils have a substantial amount of detergents in them that are there to keep particulates suspended so that they can be removed by an oil filter. The alternative to a filter is to run the tractor long enough to heat up the hydraulic system and get all the nasty stuff in suspension. Then you drain out the oil.

If you want to have a more complete draining, then there's two choices.

1. Disconnect various lines and use compressed air to force out the oil. Cylinders have to have their lines removed so they can be emptied by pulling and pushing the rod all the way out and in. It's a lot of work and the only time I believe it to be justified is when someone deliberately contaminates the system with sugar or sand etc because that stuff can get pumped everywhere before the pump fails.

2. Drain the system, refill it with 2 quarts of cheap motor oil of any grade and 2 quarts of ATF. Put the trans-axle in neutral and run the tractor at 1/4 throttle for an hour outdoors with the travel lever in full forward and then in full reverse (1/2 hour, each way). Then drain the system again, refill it with 4 quarts of the cheapest 15W40 or straight 30W you can find and allow it to run for another ten minutes. (5 min in FWD and 5 in REV) Drain it one more time and refill it with the oil of your choice.


ATF has additives in it that you won't find in regular motor oil. Cleanliness inside an automatic transmission is paramount because of the tiny passages in the "brain" of the transmission that controls which gear to be in. Therefore, ATF can dissolve things that the detergents in motor oil cannot dissolve. However, nothing will dissolve a metal particle or some other contaminants.

If your holding valve has something lodged inside it that cannot be dissolved, then it must be dismantled and cleaned. You can try the flush method I suggested if you wish but it comes with no guarantees. As Brian suggested, making sure that your engine is running at 3600 rpm is the first step of trying to figure out what's gone wrong.

 

[wurkenman]

If you need a tachometer. Here is a cheap solution. May not be the best, but it will get you closer than guessing.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260589839962&ssPageName=STRK:MEWAX:IT

 

[rwairforce]

Thanks for your advice guys..
I will get one of those tachs so I can determine my rpms and I will try the oil flush as outlined by Castoff.
What is the next step if the flush doesn't solve it? A new holding valve? Could it be the pump?