Yanmar SA424 - 1.3L 3TNV80F - engine hop up

[Erbid]

I have a small Yanmar that I dig with frequently. Newish SA434 (200 hours) with a stock 1.3L 3TNV80F engine (Thinking it may be like a JD 1025R engine ( 1.3L 3TNV80).

Problem is with a full scoop of dirt I can't drive up a steep slope! (no, I don't want a backhoe unless its scoop is about half the size of my 60" front loader bucket. Problem is the custom metal work. Waterjetting and custom bent (and terminated?) tubing for exhaust (or hydraulics) are new areas for me.

Anyhow, I'm not in a rush (6mo? 1 year? maybe later) but wondered whether you could help me figure out how to request custom fabricated parts when I need to do something beyond my skill set? I'd also love to up my hydraulic output and add some versatility (rear hydraulics, 10GPM power via hydraulics, looks easy w a tiny bit thicker pump, priority flow division to the steering with all else to accessories, except for the tubing!)

Erbid

 

[jeff9366]

Problem is with a full scoop of dirt I can't drive up a steep slope!

Is the parking brake OFF?

Are the Yanmar's rear tires turning without the tractor moving forward, creating rear tire ruts?
The burdened bucket unloads weight from your rear wheels/tires. Do you have Three Point Hitch counterbalance mounted when attempting to drive up a steep slope?

Or, the alternative, are your rear wheels/tires not turning?
Are your rear tires correctly inflated after 200 hours?
Are the rims turning within the tires due go insufficient inflation?
Or your two range HST transmission is pooping out.


Your Yanmar 434 is an 1,800 pound bare weight, subcompact tractor. This is the lightest category of Three Point Hitch tractor. Tractor weight mostly defines tractor capability.

There is little you can do to upgrade any subcompact tractor's performance. More engine horsepower, small wheels/tires and a two-range HST transmission is a zero sum.

Research 3,600 to 4,000 pound bare weight compact Yanmar tractors. A 4-WD tractor with this weight is suitable for cropping five to fifteen acres. The Loader will lift at least one ton.

Five reasons owner/operators trade up from a Subcompact Tractor:
More tractor weight.
More FEL lift capacity.
More ground clearance
Three-range (3) HST (Lower LOW, Higher, HIGH) rather than two-range (2) HST.
Larger wheels and tires yield more tractive power pulling ground contact implements and logs, pushing a loader bucket into dirt and pushing snow. Larger wheels and tires permit heavier tractors to bridge holes, ruts and tree debris with less implement and operator perturbation.

The fundamental importance of TRACTOR WEIGHT eludes many tractor shoppers. Heavier tractor weight is more important for most tractor applications than increased tractor horsepower. Bare tractor weight is a tractor specification easily found in sales brochures and web sites, readily comparable across tractor brands and tractor models, new and used.

I have owned three tractors. The first was a 1,900 pound subcompact "learner" without a Loader. The second a 2,200 pound tractor-loader package with 33-horsepower and three-range HST transmission. The third, my 3,700 pound Kubota L3560, is tractor nirvana in my north Florida conditions. Had I early read a thread philosophizing on tractor weight it would have stimulated tractor weight research and I would have omitted purchase of tractor #2, which proved too light for my applications. I purchased tractor #2 seduced by the allure of increased horsepower.

 

[Aquamoose]

I concur. Tractor is worthless if there’s no traction. Weight is detrimental to achieve any results from your tractor. Which is why I zeroed in on the heaviest tractor I can buy.

 

[bmaverick]

I have a small Yanmar that I dig with frequently. Newish SA434 (200 hours) with a stock 1.3L 3TNV80F engine (Thinking it may be like a JD 1025R engine ( 1.3L 3TNV80).

Problem is with a full scoop of dirt I can't drive up a steep slope! (no, I don't want a backhoe unless its scoop is about half the size of my 60" front loader bucket. Problem is the custom metal work. Waterjetting and custom bent (and terminated?) tubing for exhaust (or hydraulics) are new areas for me.

Anyhow, I'm not in a rush (6mo? 1 year? maybe later) but wondered whether you could help me figure out how to request custom fabricated parts when I need to do something beyond my skill set? I'd also love to up my hydraulic output and add some versatility (rear hydraulics, 10GPM power via hydraulics, looks easy w a tiny bit thicker pump, priority flow division to the steering with all else to accessories, except for the tubing!)

Erbid

Hope your Yanmar 3TNV80F get well beyond 2,000 hours in the future. My YM2610 has the first generation of your engine, it's the 3T80. Its now reached the 1,800 hours since placed in service.

Wonder if the John Deere Power Beyond or SVC would help you or a Yanmar equivalent.

 

[Erbid]

1) is the parking brake OFF?

Likely not. I bump the parking brake to start the tractor and sometimes it hangs. Adjusting the brake so it brakes when applied helped me to notice this.

2) Are the Yanmar's rear tires turning without the tractor moving forward, creating rear tire ruts?
The burdened bucket unloads weight from your rear wheels/tires. Do you have Three Point Hitch counterbalance mounted when attempting to drive up a steep slope?

Wheelspin is not an issue. I usually have a 700lb rototiller hanging a few inches beyond my 3pt hitch on a quick-hitch. I did have that issue when I tried to lift a big root. Instead of the front loader lifting, the back of the tractor wanted to go up. Not an issue with 700lbs off the rear.

3) Or, the alternative, are your rear wheels/tires not turning?

Yep, it will stall if I try to keep it above 3MPH or so. Wheels stop turning.

4) Are your rear tires correctly inflated after 200 hours?

Checked at 150hrs, visually checked daily, will check again tomorrow.

5) Are the rims turning within the tires due go insufficient inflation?

No bead slip on the tires.

6) Or your two range HST transmission is pooping out.

Still working like new, I really thought more power would help me maintain momentum. My 36hp 1957 Beetle had more power.

---

Thanks! I was having issues as well with the interplay of interlocks (brake to start) and diff-locks (if the brake is almost grabbing, the diff lock is beginning to engage, a problem on asphalt, even if you did need the engine running).

With that sorted out and a heavy implement on the rear, I have traction, but not power. If I go too slow, I can spin a tire but that is going much slower than working speed to scoop and carry dirt. If I creep, the HST will finally give me the torque I need at the tires, but it is needed at a useable speed.

If traction is moderate, four wheels drive. If traction is slippery, I get one front wheel spinning and one rear spinning. Engaging the diff lock gets me one wheel drive from the rear wheel that was not spinning. Once it spins, I rely on learned responses rather than the 4WD or Diff Lock. Mostly rocking back and forth and managing momentum better.

Power would help with momentum management.

That said, a bigger tractor would not have this problem. I recall a Versatile the neighbor had back in the 1970's. 8 tires taller than me, and better management of torque to the wheels. Heck, I don't even have "steering brakes" or a way to route power to the non-spinning front wheel. Diff lock is there to use on the rear axel, but it is odd to press pins through the differential as much beyond a parking brake. Only engage pins through diff gears at no to very low speed.

 

[WranglerX]

What RPM are you running engine at..... On my SCUT it says to run it at about 2800RPM and use HST as speed control....

 

[Yander]

A lot of tractors struggle going up a hill in a high range that's why you have a low range. I don't think your issue is lack of tractor weight at all.

If you're trying to go up a steep hill with weight on your tractor in high range that's your problem.

 

[Erbid]

I'm working in low range, RPM 2500 to 3000rpm, I bump it up to 3100rpm when working hard, and climbing steeper slopes. I've found feathering the forward pedal to have it barely crawl works. I reckon using the HST as it's lowest gear, to just creep up the slope. Makes sense thinking of it as a CVT with lowest gear being barely pressing the forward pedal (in low range).

Dumping half the load used to be the solution, just feathering the pedal works.

Thanks for mentioning low range. I use it almost exclusively, but that would have helped.

 

[Soloz2]

Messecks did a video about why you can’t climb a hill with good tips.

For modding, TractorTime with Tim turbo’d a 1025r and has some videos on it. Might be worth a watch.

 

[YanmarFever]

I THINK your tractors hyd pump is not getting enough fluid thu it.
Have you changed the hydraulic fluid and filter lately? I had a hydrostatic Mahindra with the same problem, when we changed everything, it worked great.
Also clean the screen INSIDE the tractor.

 

[Yander]

Messecks did a video about why you can’t climb a hill with good tips.

For modding, TractorTime with Tim turbo’d a 1025r and has some videos on it. Might be worth a watch.

Here it is and it is a very good video from Messecks. https://www.google.com/search?q=Mes...#fpstate=ive&vld=cid:af42906e,vid:NIEx4_fHKA0

 

[WranglerX]

Easier link to follow....

 

[Erbid]

The biggest issue is not realizing to achieve the lowest gear, feather the hydrostatic pedal. By creeping up the hill, at fll RPM, I am fighting an urge to press the pedal a bit further... I did NOT fight that urge and constantly nearly stalled.

Correct about the messic video

Thank you Soloz2!! (Yander, WranglerX) Multiple nails hit on the head. That said:

Are there any Yanmar or aftermarket parts to turbo a 3TNV80F engine? I reckon there is a part number for that engine with a turbocharger, maybe as a 32HP engine? She's just at 300hrs, fresh as a daisy.

Erbid

 

[careyo63]

No loader on my Yanmar! To light weight period. Yanmar Owners.com With no FEL. 1664 lbs.. The reason I purchased the Ford 2000 with a FEL. HP. and Weight. Many Hrs. using a JD.5103 FEL. all 2wd. Never had a problem but once and I new it and what the problem was. WET and Muddy. Sure enough and still tell my self how I didn't get it stuck! I Dumped the load in the bucket Quick before I dug in the Rear wheels. A couple pushes back with the loader and I was able to free it up! No need for 4wd. in Ga. for me anyways 40yrs. here.. Know plenty of people who do use 4wd. being Org. from WV.. It's just a little hilly. Back weight to the rears. Loaded tires and or counter weight. No matter what 2wd/4wd. You lose the rear traction chances are very high of having a big problem. JMO....... My grandfather used a 8n in the mountains. It's was a "Funk". People still actually know what that means! Were I learned what to do. Weight & HP.............

 

[EOD Retired]

No insult intented, just my understanding of some types of problems: I have a SA 425 with only about 70 hours on the clock. I've been moving full bucket loads of 3/4 minus gravel up what I consider a fairly steep driveway section without a problem (he load is nearing the lift capacity of the FEL). That's with a 470 lb box blade on the 3 pt, beet juice rears, 4wd, low gear at maximum of 2500 rpm. No problem! Steep is undefined in your senerio just has "fairly" steep is in mine. Could be a big difference in the two. Hard to know just how steep is realistic to expect any SCUT to climb with or without a load. When using my box blade I can stop the tractor cold if I put too sharp a down tilt angle on the box (not using the rippers) but its only a SCUT. I know someone with the same tractor who advised me to not buy a rear blade because this size tractor won't pull it. He says his tractor is useless for plowing snow with a 60" rear blade. I learned that he was trying to pull 23" of wet snow in high gear on a slightly uphill grade and no additional weights or chains. I think the tractor alone would have trouble driving thru that much snow without a rear blade. It seems to me that its all about the operators expectations - how he tries to use his equipment - and using the right sized tractor for the job IMHO. That said these problems often are related to mechanical troubles so....???

 

[Yander]

Putting a turbo on an increasing the horsepower will not solve this problem because it's not a horsepower problem.

It's simply the way hydraulic systems are made on every tractor that's why there are multiple ranges.

Even a gear tractor if you have it in too high a range won't pull worth a crap or climb worth a crap. You could double the horsepower and that's not going to change.

These are all things I had to learn from experience and just using multiple tractors over the years.

Everyone has to learn the limitations of their tractors the characteristics of them and how to use them and sometimes it takes a while.

 

[Erbid]

Feathering the "go" pedal to keep the HST just creeping in low range seems to work.

I saw a thread on Yahoo groups, where the opinion was posted that a turbo on a non-sleeved cylinder Yanmar would result in a short life and egg shaped cylinders balooning at the bottom, and blow-by. Re: FX22D turbocharger capabilities?

My 3tnv80f is apparently non sleeved:
https://originalparts4you.com/section/3tnv80f-snmb/cylinder-block

Just fighting the urge to use the "go" pedal like an accellerator pedal when low gear ratios are needed. I tend to drive it as if the engine speed/power and HST control are reversed when I need more torque at the wheels.

Erbid