Bolens G274 hydraulics question and issue

   / Bolens G274 hydraulics question and issue #1  

fish4life

New member
Joined
May 10, 2013
Messages
7
Location
Riverside, CA
Tractor
1988 Bolens G274
Hi all ! New member and new tractor owner here. I have been reading many posts even before I bought my tractor and saw good info here hoping I can get some and provide some to others as well.

My tractor has FEL and came with a hyd. 3 pt ram which was connected to a secondary spool valve with 2 hoses (the work lines), but that spool's IN/OUT ports where left open unconnected or plugged. So I knew I could supply power to it from my FEL valve from the PB port. But guess what!!!! there is no PB port. there is a "PB" stamp on one side but there is no hole machined there. So since it's an open center system I figure that the outlet port has to have oil going out of it in the "neutral" position anyway. So I take the outlet of the first valve off and put it into the "OUT" on the second valve for the hyd.ram. Then I get a new hose from the "out" of the first valve to the "IN" of the second valve.

Start up the tractor and the ram is working now. The 3-point hitch rasied and lowered. But then when I tried to raise the 3pt. again it would not. I put the floor jack under it and it rasied and held up. It will lower with the lever and stay in position but will not longer raise the gannon. The FEL is still working fine so that rules out a pump issue. I did not touch anything else like the slow-fast adjustment under the seat. I made sure it was all the way out. So after this I thought that maybe my hoses were not right so I put the hoses back the way they were originally...and it still doesn't work.

Is it possible that trash got pushed into the 3pt valve from the open connections or new hose? I am fairly good with mechanical things but when I cannot see the 3pt valve since it is inside the rear end case. The rear lever linkage moves as it should. All this happenned in a matter of minutes from working to no go. very strange! I am wondering if something got damaged by my hose job but if it did then it wouldn't have worked not even for the first lift.

Thoughts, questions, and possible troubleshooting techniques are welcome! thanks it's good to be a part of this forum. I can post pics of the spool valves if that helps to show that there really is no open "PB" port.

-Ed
 
   / Bolens G274 hydraulics question and issue #2  
If your valve does not have a PB port, and you are going to connect another valve, then you take the FEL OUT hose and connect it to the IN port of the new valve, and then run the OUT of the new valve to the 3pt.

Now you have a series flow.

You do know that the OUT port on most valves only have about a 500 psi rating.
 
   / Bolens G274 hydraulics question and issue
  • Thread Starter
#3  
Hi J.J. Thanks that is exactly what I did. I did'n't know the OUT would only yield 500psi but it should be enough to lift a gannon of about 600 lbs. Is my only other option to dig into the rear end to have a look and clean out the 3pt valve? Since it no longer works even when I return the hoses back to original config. No chance of airlock since open center is self bleeding correct?
 
   / Bolens G274 hydraulics question and issue
  • Thread Starter
#4  
Let me clarify. The FEL OUT already went to the 3ph so i simply put this hose (since it is long) on the new valve OUT and had a new shorter hose made up to go from the FEL OUT to the new valve IN. Same thing as you mentioned I think.
 
   / Bolens G274 hydraulics question and issue #5  
I didn't mean to imply that the OUT port is only capable of 500 psi.

That is the back pressure limit set by the manufacturer.

It is the individual hyd components that develop the hyd pressure.

If you reconnected the hose to the 3pt, it should work as before.

Do you have a hyd gage?

The hyd gage will tell you if you have pressure and how much.

Open center hyd will self bleed.

So when you pull the 3pt lever up, nothing happens?

Are you sure you connected things as before, and have a series path from pump to the tank?
 
   / Bolens G274 hydraulics question and issue
  • Thread Starter
#6  
I did connect everything the same. The 3pt went up once after I did my hose change and that's it. Now if I pull on the lever while reving engine I see a little movement in the hitch pins. Next I will remove the gannon to see if it lifts without load.

I do not have a hyd gage, but I did crack the line open at the 3pt to verify pressure and had a oil fountain. The primary oil pressure line is steel coming from the pump and runs down to a connection block on the 3pt. There are 2 rubber hoses coming out of the block. One goes to the FEL IN and the other FEL out.
 
   / Bolens G274 hydraulics question and issue
  • Thread Starter
#7  
okay so I removed the gannon box and the 3pt arms lift up very slowly only if I rev the engine up to 2500 rpm. I can stop them just by pushing them down while lever is up.

They go up faster if I drop the FEL at the same time as lifting the 3pt. Lifting the FEL and 3pt at same time 3pt does not lift at all.

3pt will stay up according to where the lever position is left.

shut off engine and I can lift the arms by hand up and down without any resistance.

what could all this mean?
 
   / Bolens G274 hydraulics question and issue
  • Thread Starter
#8  
I guess I have no choice other than to take it apart and have a look! :)
 
   / Bolens G274 hydraulics question and issue #9  
I guess I have no choice other than to take it apart and have a look! :)

The way I read your first post, you have the secondary spool valve connected backwards.

The way I read your clarification post, you have two hoses connected to FEL OUT?

Read J.J.'s post again and connect it that way.

Can you post some pictures?
 
 
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