Yanmar YM336D hydraulics stopped working. Help

Post your questions or problems you are haviing with your Yanmar tractor here.

Moderator: Aaron

Kavaman
Volunteer Poster
Posts: 10
Joined: Wed Apr 24, 2019 2:31 pm

Yanmar YM336D hydraulics stopped working. Help

Postby Kavaman » Wed Jan 08, 2020 8:51 pm

Hi, I have a yanmar 336D and I was using it and suddenly the hydraulics stopped working. The first thing I noticed was that it was harder to steer, then I tried the front bucket and it would not go up, it will go down but not up, there is no hydraulic power. It still shifts gears and drives, just hard to steer and the front bucket does not work. I checked the fluid and it is full and clean. What should I do now. Any help would be great. thanks.

Chris

winston
Volunteer Poster
Posts: 5603
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Yanmar YM336D hydraulics stopped working. Help

Postby winston » Thu Jan 09, 2020 6:19 am

Happening suddenly would make one suspect the pump has quit. However, first question would be, are you confident your spin on filter and your internal suction screen are both clean? If not, that is the place to start. Any possibility you deadheaded the hydraulics on it?

Aaron
Site Administrator
Posts: 3329
Joined: Thu Jul 26, 2007 12:39 pm
Location: Iowa Park, TX

Re: Yanmar YM336D hydraulics stopped working. Help

Postby Aaron » Thu Jan 09, 2020 3:30 pm

Most of the time when customers call about something like this- a loader hose caught on a branch or something and popped a quick disconnect fitting apart. Do you have quick disconnect fittings in your system? Any chance one disconnected?

Kavaman
Volunteer Poster
Posts: 10
Joined: Wed Apr 24, 2019 2:31 pm

Re: Yanmar YM336D hydraulics stopped working. Help

Postby Kavaman » Thu Jan 09, 2020 4:15 pm

What does it mean to deadhead the hydraulics? All the hoses are fine and still connected. I will check the filter and screen. I assume the screen is behind the filter? Thanks.

Chris

winston
Volunteer Poster
Posts: 5603
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Yanmar YM336D hydraulics stopped working. Help

Postby winston » Fri Jan 10, 2020 6:41 am

Deadheading the hydraulics would be when something stops the discharge flow of fluid such as a quick disconnect hose losing a good connection. When this happens on these the pumps will either destroy themselves or shear the coupling drive or drive key. Hopefully that is not what has happened with you. Do you have any quick connections?
#49 is your suction screen. I don't know how familiar you are with your tractor but your transmission holds around 5.8 gallons of fluid so be prepared.

Here is an example of quick connect fittings. If those become partially disconnected the flow can be stopped therefore deadheading the pump. "If the system is plumbed correctly they would be in a location that would be protected by a relief valve. It can get complicated. https://www.discounthydraulichose.com/6 ... PQQAvD_BwE
Attachments
2020-01-10-063441.jpg
2020-01-10-063441.jpg (149.5 KiB) Viewed 3587 times

Kavaman
Volunteer Poster
Posts: 10
Joined: Wed Apr 24, 2019 2:31 pm

Re: Yanmar YM336D hydraulics stopped working. Help

Postby Kavaman » Fri Jan 10, 2020 4:16 pm

I do have the quick connect hoses but they are fine, still connected and no leaks or damage. It is real wet here in Hawaii right now so I will not be able to work on the tractor. Is it hard to change the filter, screen and fluid?
Is it hard to change the hydraulic pump if I have to? I have changed the fuel pump in this tractor and that was not too bad. Thanks for all your help and aloha from Hawaii.

Chris

winston
Volunteer Poster
Posts: 5603
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Yanmar YM336D hydraulics stopped working. Help

Postby winston » Fri Jan 10, 2020 4:27 pm

No, it is not hard to change fluid, filter, clean strainer. Just to humor me, could you tell me how many quick connects your hydraulics have? Two or four?

When you look at the fluid on the dipstick or down in the sump what do you see? Look good or maybe like water in it?

Aaron
Site Administrator
Posts: 3329
Joined: Thu Jul 26, 2007 12:39 pm
Location: Iowa Park, TX

Re: Yanmar YM336D hydraulics stopped working. Help

Postby Aaron » Fri Jan 10, 2020 5:19 pm

Is it hard to change the filter, screen and fluid?

No but it is very unusual for those things to fail 'suddenly' and completely. Those usually deteriorate slowly over a period of days or weeks or months.

Is it hard to change the hydraulic pump if I have to?

It is easy to change the pump if it failed but the important thing is figuring out WHY it failed or you will get very good at replacing them. We get several angry customers a year that go through multiple pumps before they actually realize that, if they don't fix the underlying problem, they will keep buying pumps. Deadheading is not covered by warranty.

Kavaman
Volunteer Poster
Posts: 10
Joined: Wed Apr 24, 2019 2:31 pm

Re: Yanmar YM336D hydraulics stopped working. Help

Postby Kavaman » Sat Jan 11, 2020 12:37 am

winston wrote:No, it is not hard to change fluid, filter, clean strainer. Just to humor me, could you tell me how many quick connects your hydraulics have? Two or four?

When you look at the fluid on the dipstick or down in the sump what do you see? Look good or maybe like water in it?


Hi, I just checked and I have 4 of them. This was at night, I just did it now, I noticed with my flashlight that there was some fluid under the tractor, the back part. it was whitish in color and wet from the rain. I looked to see if I could see where it came from but I did not see anything, there was not much fluid maybe 1/2 quart but it has been raining so I am not sure.
I looked at the fluid and it looked normal, no water and it looked normal, I looked at the fluid inside and I looked at some that was on the dip stick.
What do you think it could be?
Thanks.

Chris

Kavaman
Volunteer Poster
Posts: 10
Joined: Wed Apr 24, 2019 2:31 pm

Re: Yanmar YM336D hydraulics stopped working. Help

Postby Kavaman » Sat Jan 11, 2020 12:38 am

Aaron wrote:
Is it hard to change the filter, screen and fluid?

No but it is very unusual for those things to fail 'suddenly' and completely. Those usually deteriorate slowly over a period of days or weeks or months.

Is it hard to change the hydraulic pump if I have to?

It is easy to change the pump if it failed but the important thing is figuring out WHY it failed or you will get very good at replacing them. We get several angry customers a year that go through multiple pumps before they actually realize that, if they don't fix the underlying problem, they will keep buying pumps. Deadheading is not covered by warranty.


Hi, what are some of the reasons that it could fail so I can check them all out. Thanks again.

Chris

winston
Volunteer Poster
Posts: 5603
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Yanmar YM336D hydraulics stopped working. Help

Postby winston » Sat Jan 11, 2020 6:26 am

Kavaman wrote:
winston wrote:No, it is not hard to change fluid, filter, clean strainer. Just to humor me, could you tell me how many quick connects your hydraulics have? Two or four?

When you look at the fluid on the dipstick or down in the sump what do you see? Look good or maybe like water in it?


Hi, I just checked and I have 4 of them. This was at night, I just did it now, I noticed with my flashlight that there was some fluid under the tractor, the back part. it was whitish in color and wet from the rain. I looked to see if I could see where it came from but I did not see anything, there was not much fluid maybe 1/2 quart but it has been raining so I am not sure.
I looked at the fluid and it looked normal, no water and it looked normal, I looked at the fluid inside and I looked at some that was on the dip stick.
What do you think it could be?
Thanks.

Chris


A pint of fluid on the ground is quite a lot. Are you saying the fluid in the tractor is not white like the fluid on the ground? No idea where your leak could be coming from, you will have to find that on sight.

Having 4 quick disconnects would lead me to believe they are on the outlets of your loader control valve and would be protected by the control valve internal relief valve.

Is this round handle valve open at least part way, not completely closed?
Attachments
IMG_1295 (1280x960).jpg
IMG_1295 (1280x960).jpg (123.94 KiB) Viewed 3542 times

Kavaman
Volunteer Poster
Posts: 10
Joined: Wed Apr 24, 2019 2:31 pm

Re: Yanmar YM336D hydraulics stopped working. Help

Postby Kavaman » Sat Jan 11, 2020 1:07 pm

winston wrote:
Kavaman wrote:
winston wrote:No, it is not hard to change fluid, filter, clean strainer. Just to humor me, could you tell me how many quick connects your hydraulics have? Two or four?

When you look at the fluid on the dipstick or down in the sump what do you see? Look good or maybe like water in it?


Hi, I just checked and I have 4 of them. This was at night, I just did it now, I noticed with my flashlight that there was some fluid under the tractor, the back part. it was whitish in color and wet from the rain. I looked to see if I could see where it came from but I did not see anything, there was not much fluid maybe 1/2 quart but it has been raining so I am not sure.
I looked at the fluid and it looked normal, no water and it looked normal, I looked at the fluid inside and I looked at some that was on the dip stick.
What do you think it could be?
Thanks.

Chris


A pint of fluid on the ground is quite a lot. Are you saying the fluid in the tractor is not white like the fluid on the ground? No idea where your leak could be coming from, you will have to find that on sight.

Having 4 quick disconnects would lead me to believe they are on the outlets of your loader control valve and would be protected by the control valve internal relief valve.

Is this round handle valve open at least part way, not completely closed?


Hi, I looked at the valve and they are not stuck open, it all seems to be normal. I started the engine while I was looking under the tractor and I found it leaking from the big hose that is coming out of the back side of the filter, the hose looks to be about 1.5" in dia. This is an obvious problem. I will fix it and see if that solves the problem. Do you think that this is the only problem? Should I change the filter and clean the screen too?
Any suggestions or pointers would be great. Thanks so much for your help. Aloha nui loa from Hawaii, wet Hawaii, waiting for the sun to come back. :)

winston
Volunteer Poster
Posts: 5603
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Yanmar YM336D hydraulics stopped working. Help

Postby winston » Sat Jan 11, 2020 1:33 pm

Sounds like the suction hose from the transmission. Could be you are sucking air. Definitely needs to be repaired. I cannot answer the question about your fluids and filter/screen. Do you have any idea when it was last serviced? Does the fluid look clean to you?

dvdhansen3
Volunteer Poster
Posts: 1
Joined: Sat Sep 05, 2020 4:44 pm

Re: Yanmar YM336D hydraulics stopped working. Help

Postby dvdhansen3 » Sat Sep 05, 2020 5:07 pm

Hi, I'm new but having similar issues with my hydraulics. I just bought this one. It has been sitting for at least 10 years. I changed all the fluids right away, I replace the water pump, thermostat, and radiator. Everything was working until the loader valve crapped out. Couldn't rebuild it, too much water and rust pits. Bought a new valve w/ power beyond port. No dice, loader and 3 pts hitch not working.
Could have dead headed, not sure. I look into the transmission tank and I can see fluid moving there. Not getting any fluid out of 3 pts hitch valve to the loader valve, so obviously no fluid returning to the tank from the loader valve. Is there any way to check the pump and or pressure? Going to try a new spin on filter tomorrow.
I hope I got on the forum correctly, thanks in advance. dvdhansen3


Return to “Tech Support”

Who is online

Users browsing this forum: No registered users and 47 guests