Engine choked down and dying without load

[Gary Fowler]

I have this problem posted on the operation forum also but it was suggested that maybe some of you folks might have an idea.
I recently bought a Yanmar 4220D and within the first few hours of running it (bush hogging) the engine would suddenly choke down and die. It was exactly like the tractor was overloaded and stalled except it would do it with the tractor setting still and in neutral. THis happened perhaps half a dozen times and the first couple of times, it had thought that the bush hog was fouled with something, but then it did it going down the driveway with out the PTO in gear. Each time the tractor made a squealing noise similar to a hydraulic pump overload sound but not high pitched
Finally after looking the entire tractor over and getting out the operating book which was almost useless. I found that the 4 wd shift lever was only partially engaged. I moved it to full engagement and it hasnt happened again although I cant imagine that that was the problem since it stalled once setting still with the tractor in neutral
ANY ONE WITH SIMILAR EXPERIENCE. THIS IS A POWERSHIFT 12FORWARD/4REVERSE 50 pto hp diesel 4 wheel drive Tractor with a FEL

 

[mark777]

Gary,

Not sure what's going on but I wouldn't think the 4WD selector and engagement isn't related to the problem. It sounds more like fuel starvation from dirt or some type of contamination before or at the FI pump. How does the fuel element and bowl look? How about the fuel tank bottom? The fuel feed (rubber) hose? Weathered and cracked hoses can allow air and cause considerable grief when trying to diagnose the problem.

Another possibility would be a badly clogged air filter element - but it would have to be extremely fouled allowing little or no air. This is where I would start....the simple things are usually the culprit.

btw, I live in Crosby too

Mark

 

[kenmac]

has it ever done this without anything connected to the PTO ? Or is it when only when something is connected to the PTO ? Is this tractor with or without the turbo ?

 

[Gary Fowler]

It did it with the PTO engaged an also without it engaged. It also stalled the engine down with it sitting still with the transmission in neutral. IT wasnt a fuel problem, the engine just choked down like it was overloaded. There was some internal noise associated like a pump was overloading but I cant believe the hydraulic pumps would have the power to stall the engine with it running full throttle. It has new filters throughout, oil, air, hydraulic. All oil levels were in operating range. This all started with only about 4 hours on the engine. After it stalled, I could immediately restart is and it would run fine for a few seconds to several minutes then would stall again. All gauges showed everything in operating range, no overheating, oil pressure was good etc.
Anyway after I parked it, read through the troubleshooting section and found nothing applicable, and then thoroughly checking all the fluids and blowing out the radiator. That is when I noticed the 4 wd shift lever in the center position between 2 and 4 wd although the tractor was still pulling in 4WD. That was the only thing that I moved and made sure that it stayed in on position or the other and I drove it hard bushhogging some waist high grass and small trees and it never did it again in the next 4 days. I burned 25 gallons of fuel and it never happened again. I suspected it was something in the Powershift transmission or hydraulic clutching but since it didnt happen again, I continued to run it. So far so good.
Just wondering if any one else has had a similar experience with their tractors. This is one of the gray market tractors that was supposedly totally rebuilt. At least it doesnt use any oil SO FAR although there are a few small leaks from somewhere around the transmission gear shift that have wet the tractor transmission case area. IT appears to be coming out around the rubber collar at the gear shift for one spot, maybe others also. I didnt have time to check it really well.

 

[SailorBob]

You might want to check the vent pipe on transmission if it has one. I had fluid coming out of my shift boot and I found dirt dabbers had tried to build a next in there. My transmission is a manual though.

 

[YanmarFever]

Gary, It looks like you have gotten some excellent advise from the others, and you have all the fluids & filters covered.

Sometimes I have to adjust the lever handle on the 3 point lifts, we get some tractors that squeal like crazy until you make the adjustment.

Its when you lift it all the way up, it will bog down the engine and leave you wondering what happened

 

[kenmac]

did you have it rebuilt & know it only has 4 hrs on it ? Or were you told this by the seller ? Most (or none) of these tractors are totally rebuilt.

 

[Gary Fowler]

This is just told by the dealer that they are rebuilt to 90% or new spec. to which I didnt attribute the whole truth to. However I figured that if it ran ok for the 90 day warranty period, it would likely be OK. Even if they inspect and rebuilt as claimed, they tell you that they reuse any parts that are within the 90% or new. They reset the hourmeter to 0 and I suspect this is just so they know how many hours you ran it in those 90 days more than anything else, plus there is then no way for the buyer to know how many actual hours have be put on the tractor. Since most folks think a tractor with 1000 hours is worn out, it calms those fears when they dont know.
Having said that, the engine does appear to be in as good shape as new tractors at least from my experience with new back in the 60-70s. Even new diesel tractors back then would use a quart of oil per day when heavily loaded. I put 25 hours on this one pulling 6 foot brush hog in heavy cover and it didnt use any oil so it appears the rings are good at least. THe hydraulics seem a little weak on the FEL but I may just be expecting too much for the 45 HP tractor. I bought a 8 foot tandem disc and had trouble getting it off the trailer with the FEL. It wouldnt pick it up with the arms but I managed to lift it by curling the bucket. THe specs on the disc said it weighed 1600 but the previous owner had welded about 10 feet of heavy railroad track on top to give it more weight so I dont know what the actual weight was. Once I got it off the trailer, it carried it well to where I set it down for storage.
I havent tried to see if the 3 point will lift it as it had Category 2 pins in it and the threads were banged up and the tools I had available were not sufficient to loosen the nuts.

Well back to the original problem. I suspect the problem had something to do with the hydraulic clutching mechanism in the powershift although I dont know how it could stall the engine unless the hydraulic feed to that does not have a pressure relieve device like was mentioned with raising the lift too high. In that case, something must be out of adjustment because the pump should not continue to put pressure on a cylinder after it reaches maximum extension.