Jump to content

656 gear drive cavitation


Tom74

Recommended Posts

I’m getting ton of whine from the hydraulic pump.  It tends to get much better if I over fill it.  I’m assuming the issue is with the suction tube seal.   Where is this located and do I need to split the tractor to fix it? 

Link to comment
Share on other sites

Check to see that the filter gasket surface is cleaned on both sides -- and that the correct bolt length have been used to hold the cover on

Check the suction jumper tube for the pump -- the jumper can get out of place -- or the seal can shrink away from the housing and suck air
-- if the pump has been replaced , the length of the jumper tube needs to be checked , as that is what holds the jumper in place

Check the super charge line as was suggested by @mrfred54  accessed thru the top link cover

The last place is the suction oring in the rear housing / transmission split

Do the easy stuff first , then work to the harder stuff

Link to comment
Share on other sites

Thank you! I was wondering if that tube may be an issue.    I just did a ton of work to my loader (resealed the cylinder and new hoses).  I should probably change the filter anyway.   Only question I have is why will the wrong bolt length affect the whine? I could see it causing a leak.  But maybe I’m missing something.    I’m positive I have the correct length in thought.   I believe ther E are 2 bolts that are shorter due to a recessed hole.  

Link to comment
Share on other sites

That filter gasket was sometimes difficult to remove from the surface -- if you don't get all the small parts off , air can be sucked thru the uneven surface -- just be sure the metal is cleaned

With the age of the tractor , hard to know that the cover bolts are correct
my comment was just to cause you to look and see that the bolts are not bottoming out

Link to comment
Share on other sites

that creates an obvious leak  if oil level is correct I'd pull the pump and check for bolts and Oring the bolts can be checked for tightness on the outside near the step

Link to comment
Share on other sites

2 hours ago, ksfarmdude said:

that creates an obvious leak  if oil level is correct I'd pull the pump and check for bolts and Oring the bolts can be checked for tightness on the outside near the step

"what you talking about willis"

The pump mounting bolts or plate has nothing todo with the suction side of the system -- only the jumper tube fitment in that area

Link to comment
Share on other sites

It will if the oil level is low in that area if there's any pump issues it can cause any type of problem I would suggest he do pressure tests plus see what flow he has and check for air bubbles if there's air present Never seen the oil filter plate cause  problems anyone with mechanical skill can change the filter and install a new gasket and check for a leak doesn't take a rocket scientist to figure that one out 

Link to comment
Share on other sites

If your pump is whining change your filter before you do anything.  Talking from experience.  Mine clogged up with sludge 2 years in a row for reasons unknown and then was fine this year.

Link to comment
Share on other sites

2 hours ago, hobbyfarm said:

If your pump is whining change your filter before you do anything.  Talking from experience.  Mine clogged up with sludge 2 years in a row for reasons unknown and then was fine this year.

Reasons aren't unknown :
Those tractors do not like getting wet
Water will drain into the transmission at the "pockets" on the floor plate -- and run in around the bolts
and at the top of the transmission to rear housing split -- there are no bolts in the center of that split at the top , and a pocket of sorts that collects water
Put your 656 - 686 in the shed

Link to comment
Share on other sites

7 hours ago, HydroTek said:

Reasons aren't unknown :
Those tractors do not like getting wet
Water will drain into the transmission at the "pockets" on the floor plate -- and run in around the bolts
and at the top of the transmission to rear housing split -- there are no bolts in the center of that split at the top , and a pocket of sorts that collects water
Put your 656 - 686 in the shed

I will say I have probably had this tractor 15 years and it doesn't sit out.  In that time frame it has had 3 hydraulic filters.  One after I got it, one in 2021, and one in 2022.  To the original poster I would think it is sound advise to change the filter before doing anything else.

Link to comment
Share on other sites

Sitting out , is not the issue

Getting rained on is tho , as well as washing in the area of the steering column

Moisture will also enter thru condensation
that is why the recommendation of oil change every 2 years , or 1000 hours
Most do not change oil until there is a problem or a major leak

Link to comment
Share on other sites

  • 2 weeks later...

Thank you all for the help.   I’ve been a little busy the last few weeks, but all the hay is put up and I have some time for maintenance.  
So, I’m going to change the hydraulic fluid this week.   I’m going to pull the pump, replace any o rings I come across and just make sure they system is sealed up.    If I take the top cover off the gearbox, can I get to that suction tube hose? Or can I even see it from the top so I can do a better inspection of it?    I like to know what I’m getting into before I open something like this up, but I’m not finding many pictures on line.  

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...