TC!8 Engine bogging down

[OkeeDon]

There's one section of my 5 acres I had pretty much ignored most of the summer while I was working on other areas. It's been real wet and the grass grows fast in Florida. I finally went in there with my TC18, hydro, and 4' brush hog to get the thick, wet grass back under control.

With only about 15 PTO HP, I've gotten used to the mower bogging down every once in a while. Usually, if I lift it, it will come right back up to speed, I can back up a bit and let it back down and keep mowing. If it's really thick (as this was) the hydro is great for just creeping along.

This time, when the mower started bogging and the engine slowed, I couldn't get it to come back up to speed. I lifted the mower, depressed the clutch, took the PTO out of gear, put the hydro in neutral, and the engine kept running slowly. It never quite stalled, and would try to build back up to PTO RPM (around 2450), but something was still slowing it down. But, what? Nothing was connected, and the PTO shaft wasn't turning.

Eventually, it cured itself (after about 5 minutes of waiting), and I mowed for another hour or so without problems. Then, it did it again. I tried some other combinations. With everything in neutral, I worked the hydro pedals and it seemed like it came back up a little faster. I also found that if I lowered the throttle to about half way, it would pull down to about 1000 but wouldn't stall, and seemed a little easier to get it back up to speed.

Over the course of about 6 hours (the grass was really thick, and I think I was mowing at about 1/10th MPH), it did it a couple of more times. But, most of the time it was OK - the mower might bog, but it came right back to speed as it always has. There didn't seem to be any rhyme or reason why sometimes I would have the problem and other times not.

The only thing I can figure is that maybe I got the hydo too hot or something, or something in the PTO was binding. The hydro fluid is full. The tractor has about 250 hours.

Today, I finished the mowing and it was OK all day - no problems.

Any clues what might have happened, and is it a symptom of some greater problem?

 

[DUMBDOG]

Check the fuel filter as I had somewhat of the same problem, bogging on occasion, cleaned the filter, got rid of the crud in the filter bowl and the situation was back to normal.

 

[jinman]

Don, I think especially in a high humidity area, you might be experiencing some condensation water in your fuel. It really sounds like some form of foreign material either in your fuel or stopping up the flow. Like David suggested, the fuel filter and bowl is a good place to start looking for the problem. Problems that come-and-go are almost always fuel related. You might have some trash/obstruction in your fuel tank. Was the level low or did you have a full tank? I think it also could be hot-engine related. Does your tractor have a heat gage or a light? If it's a light, you might need to check your heat switch. Did you have any blockage of your radiator? ...just a couple of suggestions

 

[rambler]

Well, does the engine sound like it is really working hard? Probably not. If so, could possibly be the tranny/ etc. I would really doubt it.

Does it sound more like it's weak, or starving for something? Clean out the fuel filters - this will be your problem 95% of the time. Check for water in your fuel tank - that's really bad for a diesel, the pump hates water.

My combine did this once, cleaned & replaced filters & watched for flow.... Two days I dealt with this, I was sure it was a major $$$$ problem. Finally traced the fuel line & found a sediment bowl with a mesh screen in line under the dust. Dumped out the bowl, blew off the screen with my windy breath, and it has run terriffic for 2 years!

--->Paul

 

[OkeeDon]

All of you point to the fuel, so obviously that will be the first thing I check. It just seemed strange to me that it entirely mimicked the bogging caused by the mower, and only happened when I was running the PTO to drive the mower. Sequence is this: tractor running at around 2400, mower bogs down, tractor slows to, say, 1200 or 1500, then wavers briefly while coming back up to speed - up to 1800, back to 1600, up to 2200, back to 1800, then finally back up to 2400 and everything is normal, again. If I leave the mower down in the thick grass, it would take much longer to come back up to speed. Lifting the mower with the 3PH lets it come back to speed almost immediately

However, several times, lifting the mower would not let the engine recover. I press the clutch, then shift off the PTO, then put the hydro in neutral, and it still wavers between, say, 1200 and 1800, with no change in the throttle setting. The thing that scared me, is that if I cycled the hydro pedal (which is a foreward and backward treadle on the TC18), even though the range lever is in neutral, it seemed to relieve whatever was making it bog, and let it come back up to speed a little sooner. I subsequently ran it for about 4 hours with the box blade and it was perfect.

But, the fuel filter is a good place to start. The tractor has been sitting outside for a couple of weeks, and we have had almost constant rain. There could be some water. I hope that's all it is; I can handle that!

Unfortunately, I'm back home now, and the tractor is 45 miles away, and I won't be going back out there for a week or so due to other commitments. So, I won't be able to check it and I'll be on pins and needles until then.

Thanks for all the replies. I'll let you know what I find once I get the chance to check it.

 

[thcri]

Don,

My TC29D did that the first night I got it home. The dealer came out the next day and we took the fuel bowl off and it was full of crud. We ended up flushing the tank out a couple of times and I will still change that filter about every 50 hours and there will be crud in the bottom of the bowl. I also put conditioner in the fuel about every 5 tanks or so especially in the winter.

When taking the bowl off make sure you have the gas shut off right by the bowl and when replacing make sure the bowl is full right to the top with fuel when replacing, it will spill out some while pushing the bowl up around the new filter but you have to have no air in the bowl.

murph

 

[cdcole]

Mine turned out to be a fuel issue - read this thread.

The reason it happens under load is because that is when the engine needs the most fuel supply.

Darn I felt stupid for not figuring this out sooner.

Had nothing to do with heat, engine failure, etc.. And everything to do with the fuel.

Check out this thread. Thread on engine idling back

 

[Soundguy]

Might also check air filter. Some of that heavy mowing might be dislodging lots of fluff to clog up the air filter ( or even the radiator screen ).

Soundguy

 

[OkeeDon]

I'll check the air filter too; the radiator screen is the first thing I checked, because I usually have to clean it about once a day. But, the grass was so wet this time, it wasn't blowing around. In fact, in some places I was mowing though 3" to 9" of water; I adjusted the height of the brush hog by listening to the motor boat sounds the blades were making... /forums/images/graemlins/crazy.gif

 

[OkeeDon]

I got out to Okeechobee today and looked at the fuel filter. It is cruddy. Problem is, I couldn't get it apart. The loader frame runs right across the big nut that holds the bowl on, there are hydraulic lines above and below the loader frame, and I couldn't get water pump pliers on it. I tried putting a screwdriver on one of the lugs and tapping it, but it's on there too tight. There isn't much room to work. I hate to admit defeat, but it started raining (again) while I was working on it, so I quit. I moved it out by the gate and am calling the dealer in the morning to stop by and clean or replace it.

I didn't have my owner's manual with me.

Is there a special tool, or some trick, to getting the thing loose?

I did run it for a bit, and it's getting worse - bogged down trying to pull the box blade without much resistance against it. So, I guess it is the filter.