YM226D Project

   / YM226D Project #1  

tc197

Bronze Member
Joined
Jan 9, 2021
Messages
63
Tractor
YM226D
Hi, I've been reading and observing for a few weeks now collecting information as I go. Thanks for the help so far. I have a YM226D with a front loader that I recently inherited that I am working on getting running. It's been sitting outside under a deck for the last 5-10 years untouched until it was given to me by some family. I have a couple issues I am working through and was hoping to get some advice before I start tearing things apart.

So far I've drained and replaced the diesel, changed the fuel filter and bled the lines according to the Hoye site, changed the engine oil and filter, replaced the thermostart glow plug, and spliced in a lower radiator block heater. I have a fresh battery and have been somewhat successful in getting the tractor to start. The colder it is, the harder it is to start and the other day when it was about 20 out even the radiator hose heater wasn't getting it done. I am following the recommended starting procedure with the throttle all the way forward, using the thermostart for 30 seconds two times, pulling the decompression lever and cranking and releasing. once I can get the tractor started I have three main issues.

1. The tractor is leaking engine oil. I have a consistent drip when running that is coming from the weep hole in the bottom of the bell housing. It is not hydraulic oil. Based on my research I believe this would indicate a rear main seal issue but was looking for any other possibilities before I go down that road. It's probably a drip every second or two and not something that I would run as is.

2. Despite all of the posts about Yammer-Hammering I think I have extra noise and it does not sound smooth to me, especially at lower RPM's. I hear inconsistent knocking and not just a smooth diesel rumble like my fathers BX series Kubota.

3. Possibly linked somehow to number 2, I have weird surges and control issues with the RPM's. It will respond to the throttle but not in a consistent manner. If I try to set the tractor at any RPM, within a few seconds it is either dropping in RPM's and stalling or surging and heading to redline. All of my throttle control is over an inch or two of travel and requires constant babying to stay away from redline but not stalling. I have adjusted the throttle friction nut so it is not the throttle sliding up and down. If I hold the throttle in one position I still get the increase or decrease of RPM's. I get some white smoke when cranking and starting but once it is running the smoke goes away. I will get some black smoke if I throttle the RPM's up but only for a second. Any thoughts on what might cause this?

Thanks in advance for any input and I look forward to getting these issues sorted out!
 
   / YM226D Project #2  
Hi, I've been reading and observing for a few weeks now collecting information as I go. Thanks for the help so far. I have a YM226D with a front loader that I recently inherited that I am working on getting running. It's been sitting outside under a deck for the last 5-10 years untouched until it was given to me by some family. I have a couple issues I am working through and was hoping to get some advice before I start tearing things apart.

So far I've drained and replaced the diesel, changed the fuel filter and bled the lines according to the Hoye site, changed the engine oil and filter, replaced the thermostart glow plug, and spliced in a lower radiator block heater. I have a fresh battery and have been somewhat successful in getting the tractor to start. The colder it is, the harder it is to start and the other day when it was about 20 out even the radiator hose heater wasn't getting it done. I am following the recommended starting procedure with the throttle all the way forward, using the thermostart for 30 seconds two times, pulling the decompression lever and cranking and releasing. once I can get the tractor started I have three main issues.

1. The tractor is leaking engine oil. I have a consistent drip when running that is coming from the weep hole in the bottom of the bell housing. It is not hydraulic oil. Based on my research I believe this would indicate a rear main seal issue but was looking for any other possibilities before I go down that road. It's probably a drip every second or two and not something that I would run as is.

2. Despite all of the posts about Yammer-Hammering I think I have extra noise and it does not sound smooth to me, especially at lower RPM's. I hear inconsistent knocking and not just a smooth diesel rumble like my fathers BX series Kubota.

3. Possibly linked somehow to number 2, I have weird surges and control issues with the RPM's. It will respond to the throttle but not in a consistent manner. If I try to set the tractor at any RPM, within a few seconds it is either dropping in RPM's and stalling or surging and heading to redline. All of my throttle control is over an inch or two of travel and requires constant babying to stay away from redline but not stalling. I have adjusted the throttle friction nut so it is not the throttle sliding up and down. If I hold the throttle in one position I still get the increase or decrease of RPM's. I get some white smoke when cranking and starting but once it is running the smoke goes away. I will get some black smoke if I throttle the RPM's up but only for a second. Any thoughts on what might cause this?

Thanks in advance for any input and I look forward to getting these issues sorted out!

Welcome to the forum! There are many many folks on here that are great resources here. I am sure you will get lots of help.
My opinion but typically we do not talk about a redline RPM’s on our tractors. You probably need to explain what you mean in more detail. As a side note, Tractordata.com list your working RPM at 2600 (this would generate 540 PTO RPM in PTO speed 1, if multiple speeds)
Your smoke description sounds pretty normal based upon what you say. Also when using the tractor when a heavy load (PTO or ground engaging) expect some black smoke. Probably more than a brief puff.
The rough running sounds like an issue that needs to be corrected. It is difficult to advise you without hearing the sounds. It could be as simple as a poorly performing injector due to sitting and a gumming effect. A good diesel additive/injector cleaner may correct this over time. If you do not wish to wait (understandable) use an additive conditioner for fuel anyway (diesel in 2020’s is very different than diesel in 1980’s). If you want to be proactive on the knocking, one at a time verify that fuel is getting to each injector by loosing each metal line at the injector. If fuel is getting to each injector, plan to pull the injectors and clean them. There are videos of how to clean them on Youtube. And yes a surging is probably related to a poor fuel delivery issue.
As for the oil leak, you will have to split the tractor to replace the rear seal. If the oil getting into the Bell Housing is sufficient to coat the clutch, you run the risk of other damage to other components.
I would be concerned about the amount of oil inside the Bell Housing as well as how much drips out over a period of time. I suggest you get a paint mixing container that has marked measurements on it. Run the tractor for a set period of time (measure) then collect the dripping oil over an extended period (ie 1day). This gives a good feel for exactly how much oil you are loosing. It is possible that the seal may have dried out and loose less as it runs longer. But at 40 yrs old don’t count on it.
A couple of other areas you want to address.
1) change the hydraulic/transmission fluid and. Clean the screen. All of these tractors have a tendency to allow water to seep into the reservoir. Only way to avoid is to store them out of weather.
2) same water issue but in the steering box. Water runs down the steering column and collects in the steering box. Since oil is lighter than water, the oil floods out.
 
   / YM226D Project
  • Thread Starter
#3  
Welcome to the forum! There are many many folks on here that are great resources here. I am sure you will get lots of help.
My opinion but typically we do not talk about a redline RPM痴 on our tractors. You probably need to explain what you mean in more detail. As a side note, Tractordata.com list your working RPM at 2600 (this would generate 540 PTO RPM in PTO speed 1, if multiple speeds)
Your smoke description sounds pretty normal based upon what you say. Also when using the tractor when a heavy load (PTO or ground engaging) expect some black smoke. Probably more than a brief puff.
The rough running sounds like an issue that needs to be corrected. It is difficult to advise you without hearing the sounds. It could be as simple as a poorly performing injector due to sitting and a gumming effect. A good diesel additive/injector cleaner may correct this over time. If you do not wish to wait (understandable) use an additive conditioner for fuel anyway (diesel in 2020痴 is very different than diesel in 1980痴). If you want to be proactive on the knocking, one at a time verify that fuel is getting to each injector by loosing each metal line at the injector. If fuel is getting to each injector, plan to pull the injectors and clean them. There are videos of how to clean them on Youtube. And yes a surging is probably related to a poor fuel delivery issue.
As for the oil leak, you will have to split the tractor to replace the rear seal. If the oil getting into the Bell Housing is sufficient to coat the clutch, you run the risk of other damage to other components.
I would be concerned about the amount of oil inside the Bell Housing as well as how much drips out over a period of time. I suggest you get a paint mixing container that has marked measurements on it. Run the tractor for a set period of time (measure) then collect the dripping oil over an extended period (ie 1day). This gives a good feel for exactly how much oil you are loosing. It is possible that the seal may have dried out and loose less as it runs longer. But at 40 yrs old don稚 count on it.
A couple of other areas you want to address.
1) change the hydraulic/transmission fluid and. Clean the screen. All of these tractors have a tendency to allow water to seep into the reservoir. Only way to avoid is to store them out of weather.
2) same water issue but in the steering box. Water runs down the steering column and collects in the steering box. Since oil is lighter than water, the oil floods out.

Thanks for quick and well detailed response!

I believe my understanding of redline was incorrect for this tractor. On my gage I have a red line at just past the 2500 rpm mark. I see now that this most likely indicates the working rpm's of 2600 as you pointed out. The gage max is 3000 rpm. I was getting nervous watching the rpm's surge to 2600+ thinking I was "redlining" the tractor. Is it possible for these diesels to overrun and do damage or is that not something I need to worry about?

I did add a diesel injector cleaner as well as an anti-gel due to the cold weather just the other day. This is my first time working with diesel so I was surprised to learn that gelling is an issue. My biggest concern with the knock was doing extra damage for running it longer. I will verify fuel delivery at the injectors and start there. As an additional thought - a lot of the soft fuel lines are past their prime and I'm tempted to replace them. Is there a recommended process to avoid sucking a bunch of air into the system? After seeing how detailed you need to be when changing the fuel filter I can only imagine the troubles that could arise if I load the lines with air.

Great idea with the oil vs time measurements, I will do this as well. My plan right now is to try to fix any issues I know of before splitting the tractor if it ends up needing to go that way. This way, when I put it back together, I know anything not working properly is directly related to my rear main seal fix.

I will change the hydraulic fluid. I held off on this initially because it looked clean, at the proper level, and the front loader has motion. I already have the new filter but had just prioritized some of the other issues ahead of this.

Good to know about the steering box. I will have to do some research on this.
 
   / YM226D Project #4  
My yanmar is a grey where yours was USA build, but my understanding is most if not all the USA models have a grey counterpart model or one very similar at least.
Gelling of diesel is an issue has there are different numbers of diesel (#1 & #2). Basically that is warm weather and cold weather fuel. Because of the age of my model (only built in ‘82 & ‘83) I use a conditioning additive with every tankful of fuel. The additives I use for conditioning contain an anti-gelling additive so win win on that.
As for replacing your soft fuel lines, try to do them all at the same time, tank to filter is a pain if no shutoff at the tank (mine does not have at least. Ot when it found its way to me). It is never a hood ideal to run a diesel dry of fuel by the way. Replacing all the lines at once means you only have to bleed the fuel system once as it can be a drawn out process. This could be feeding your knock condition, a failure of the injection pump to have a sufficient fuel supply could be randomly starving injectors from enough fuel to fire correctly as they pop off of pressure mechanically not based on an electronic signal as a modern fuel injected car (no computer present).
The potential issue for your hydraulic fluid looking fine but containing water is that if looked at resting, oil and water will separate with oil on top. Looking from any opening will look good. Checking the dipstick for fluid level will look fine. Overfull would be a large indication of potential water. If checked while running or just after shutting it down, a milky or frothy appearance is a sure sign of water in the oil.
A rear engine seal in a tractor is similar to a rear seal on a car. The transmission must be removed from the engine. The big difference for a tractor is that you end up 2 pieces of tractor, each piece with one axle. Both half’s will need extra support. Be sure you have help on hand. Best if someone has done it before is around, even if like me and would mot attempt it any longer (back problems that make tugging on that heavy uncooperative half’s a bad ideal).
 
   / YM226D Project
  • Thread Starter
#5  
Tried to do some of the checks you mentioned today but couldn't manage to get the tractor started. I have a service manual on order and am waiting to start the bigger jobs until that arrives. I was able to verify that I have fuel reaching each injector and am waiting for the service manual for details on pulling the injectors to clean them. I wasn't sure how much of an overlap there is amongst various diesel engines and was getting confused trying to google the removal process. It seems that I will be removing the hard lines, removing the retaining collar, and using a puller. I will change out the soft fuel lines at the same time and go from there.
 
   / YM226D Project #6  
Tried to do some of the checks you mentioned today but couldn't manage to get the tractor started. I have a service manual on order and am waiting to start the bigger jobs until that arrives.

See attached
 

Attachments

  • YANMAR YM226 PARTS MANUAL.pdf
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   / YM226D Project
  • Thread Starter
#7  
See attached

Thanks bmaverick, I do have a copy of the parts manual as well as the operation manual. I'm assuming the service manual will have a good description of how to remove the injectors and how to split the tractor to get at the rear main seal.
 
   / YM226D Project #8  
I would be checking the governor spring.
 
   / YM226D Project
  • Thread Starter
#9  
Well my service manual came in and it looks to be full of great information. One thing I'm having trouble finding is details on removing the injectors. Do I need a special tool to pull the injectors like what is sold on the Hoye site? The only information I can find in the service manual says "Remove retainer from top of each injection nozzle. Remove injection nozzle from cylinder head."
 
   / YM226D Project #10  
Sometimes they come out easy, sometimes they don't. Yours could be either. I have read of loosening hold down bolts and spin engine to blow them loose. Do not remove hold down, just loosen if you try this. :eek:
 
 
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