Brew Posted February 9, 2022 Share Posted February 9, 2022 Can someone point me in the direction of where the relief valve on this tractor is. I changed the main pump, put new fluid in and I’m still getting no rear hydraulic lift or remotes. I have the relief valve, just don’t know where to put it. Thanks. Quote Link to comment Share on other sites More sharing options...
CIHTECH Posted February 9, 2022 Share Posted February 9, 2022 Right side seat riser, thin head 1-1/8 hex head. Should have part # stamped in it 1 Quote Link to comment Share on other sites More sharing options...
Jeff-C-IL Posted February 9, 2022 Share Posted February 9, 2022 I'm sure somebody will chime in with a picture, but essentially its a plug on the right side of the rear end cover, below the operators seat, in front of the remote lever assembly. Its just above the operator platform. Can't remember any more if its a 15/16 or 1-1/8" socket. IIRC, there are 2 similar plugs in that area, one is just a plug, the other is the valve. It will be obvious when you pull it out. (How quickly we forget things we have done a dozen times...) 1 Quote Link to comment Share on other sites More sharing options...
mrfred54 Posted February 9, 2022 Share Posted February 9, 2022 Good time to change the internal oring while your changing the valve Quote Link to comment Share on other sites More sharing options...
Brew Posted February 9, 2022 Author Share Posted February 9, 2022 31 minutes ago, mrfred54 said: Good time to change the internal oring while your changing the valve Is that with the valve? Or in the opening? The new valve has a new oring on it. Thanks. Quote Link to comment Share on other sites More sharing options...
Jeff-C-IL Posted February 9, 2022 Share Posted February 9, 2022 Again, I forget so easy, but I think there is an oring inside the housing, not the one that seals the threads on the valve itself. Look inside the bore where the valve goes (if you can get your head there...). Quote Link to comment Share on other sites More sharing options...
TB5288 Posted February 10, 2022 Share Posted February 10, 2022 2 hours ago, Brew said: Is that with the valve? Or in the opening? The new valve has a new oring on it. Thanks. There is an o-ring on the valve as you mentioned and also one in the bore. Can be a bit of a challenge to replace. Quote Link to comment Share on other sites More sharing options...
Michigan No Till Posted February 10, 2022 Share Posted February 10, 2022 How far in is the internal o ring? If it's bad, does it allow pressure to bypass? Will this be the same procedure and parts for the 756? With a good set of o ring picks, will it be hard to renew the internal o ring? Jeff has said in the past to upgrade to a 66 or 86 series pressure relief valve. 756 remote's and 3 point work, just slow to raise. Quote Link to comment Share on other sites More sharing options...
Jeff-C-IL Posted February 10, 2022 Share Posted February 10, 2022 All the 706-1486 series (open center) tractors are the same. Just used different valves to bump up the pressure. A good set of oring picks and patience should get the job done...some cabs make it real difficult to get to/see the spot. Changing the pressure regulator to a higher pressure one will get the tractor to lift more. That said, if your current pump is weak (low flow), it may not help your lift speed. These old OC systems were very straightforward. The pump created XX gpm flow, the pressure relief set the maximum pressure. So when you loader would not lift the manure bucket, or it barely would lift the planter full of seed & fertilizer, you put the higher pressure regulator in it, and Voila! But that will not correct a poor pump that could not produce flow or enough pressure to open the relief! So on your 756 your slow lift could be low pressure or low flow...put in a higher pressure relief and see if it is better. If not, the pump probably needs service. Quote Link to comment Share on other sites More sharing options...
Michigan No Till Posted February 10, 2022 Share Posted February 10, 2022 Thanks so much, going from a 12 gpm to a 17gpm help out any if the pump needs replaced? There's a o ring behind the pump mounting plate to rear end housing, if I'm understanding some of the older posts and I rings that are on the suction tube also? Quote Link to comment Share on other sites More sharing options...
Jeff-C-IL Posted February 10, 2022 Share Posted February 10, 2022 Yes. Oring (and a teflon ring upgrade) behind the pump plate. Orings on the suction tube. As far as going from 12-17 gpm, that will definitely help the flow but, also remember that more flow takes more HP - which on a smaller tractor may be a noticeable drag when lifting. Do you need the higher flow, are you lifting a loader with large cylinders? Need your 3pt mower to "snap up"? In general, the 17 gallon is probably the better choice, I just wouldn't change it unless your current pump is bad, or you need the higher flow. Quote Link to comment Share on other sites More sharing options...
Michigan No Till Posted February 10, 2022 Share Posted February 10, 2022 16 minutes ago, Jeff-C-IL said: Yes. Oring (and a teflon ring upgrade) behind the pump plate. Orings on the suction tube. As far as going from 12-17 gpm, that will definitely help the flow but, also remember that more flow takes more HP - which on a smaller tractor may be a noticeable drag when lifting. Do you need the higher flow, are you lifting a loader with large cylinders? Need your 3pt mower to "snap up"? In general, the 17 gallon is probably the better choice, I just wouldn't change it unless your current pump is bad, or you need the higher flow. Thanks so much, going from a 12 gpm to a 17gpm help out any if the pump needs replaced? There's a o ring behind the pump mounting plate to rear end housing, if I'm understanding some of the older posts and I rings that are on the suction tube also? Just need to pick up 7000 jd 4 row with liquid and 3 Rawson's/row. Heavy 3 by 6 frame with extended tongue, and 70 gallon pop-up tank on tongue also. Having to stop on head land is a slow process.. To lift it up. Quote Link to comment Share on other sites More sharing options...
Jeff-C-IL Posted February 10, 2022 Share Posted February 10, 2022 I think I would put the 2300psi series pressure relief in it, and try it. Slow raise on a planter is a PAIN. I've never run a 756, I think the original relief was - 1600psi? You can get 2000, 2300, 2500 for the 66 series. (do remember that higher PSI also means more likely to find "weak points"/ leaks!) Then if the lift is still slow, change the pump out. My 806 with a 2000psi valve would raise my 8 row 7000 with liguid starter acceptably. Original pump, as far as I knew. Please, some other guys chime in here to agree or disagree. This is a great group experience topic! Quote Link to comment Share on other sites More sharing options...
snoshoe Posted February 10, 2022 Share Posted February 10, 2022 1 hour ago, Jeff-C-IL said: Please, some other guys chime in here to agree or disagree. You're doing fine. Quote Link to comment Share on other sites More sharing options...
Michigan No Till Posted February 10, 2022 Share Posted February 10, 2022 Thanks again, someone here has said in the past to also remove the upper link mount and watch relief valve flow with a remote lever dead headed? Quote Link to comment Share on other sites More sharing options...
Brew Posted February 10, 2022 Author Share Posted February 10, 2022 Ok all new o-rings, new relief valve, new pump and new fluid and still no rear remotes or 3 point hitch. What’s next? Any suggestions? Fluid looks like there are air bubbles when I let it idle for about 30 minutes to let fluid circulate and re checked. Thanks. Quote Link to comment Share on other sites More sharing options...
snoshoe Posted February 11, 2022 Share Posted February 11, 2022 8 hours ago, Michigan No Till said: Thanks again, someone here has said in the past to also remove the upper link mount and watch relief valve flow with a remote lever dead headed? Oil should be coming down right rear. With valve dead headed. Oil is still coming down there only now it is either going through or around relief valve. If flow slows or stops. The oil is going somewhere else or the pump can't pump it. Quote Link to comment Share on other sites More sharing options...
snoshoe Posted February 11, 2022 Share Posted February 11, 2022 4 hours ago, Brew said: Ok all new o-rings, new relief valve, new pump and new fluid and still no rear remotes or 3 point hitch. What’s next? Any suggestions? Fluid looks like there are air bubbles when I let it idle for about 30 minutes to let fluid circulate and re checked. Thanks. Got an idea it's a suction tube problem or the pump isn't turning. Need to know if seal is pressed on tube or in housing. Also how you installed tube. See my response to no till above. 1 Quote Link to comment Share on other sites More sharing options...
Jeff-C-IL Posted February 11, 2022 Share Posted February 11, 2022 Does the PTO work? IF not you could have driveline problems. Quote Link to comment Share on other sites More sharing options...
Brew Posted February 11, 2022 Author Share Posted February 11, 2022 27 minutes ago, Jeff-C-IL said: Does the PTO work? IF not you could have driveline problems. Yes pto is working. It’s raining down from relief valve. And it looks to be raining down and aerating and getting bubbly towards the front of the housing. Quote Link to comment Share on other sites More sharing options...
hippy5488 Posted February 11, 2022 Share Posted February 11, 2022 10 minutes ago, Brew said: Yes pto is working. It’s raining down from relief valve. And it looks to be raining down and aerating and getting bubbly towards the front of the housing. raining down left front or right front? Quote Link to comment Share on other sites More sharing options...
Brew Posted February 11, 2022 Author Share Posted February 11, 2022 28 minutes ago, hippy5488 said: raining down left front or right front? From the back looking forward. Looks to be from the left side. Quote Link to comment Share on other sites More sharing options...
Jeff-C-IL Posted February 11, 2022 Share Posted February 11, 2022 Could the oring/seal be gone between the case and the top cover? Isn't that about the only thing that is on the left side top?? Even if it was, I would think it would be spraying out sideways not just running down.... Quote Link to comment Share on other sites More sharing options...
Michigan No Till Posted February 11, 2022 Share Posted February 11, 2022 Sounds like a pita. Hope not, Brew doesn't need any more headaches. Is Red run rite have a good reputation? They have the 2000 psi valve. 180 bucks Quote Link to comment Share on other sites More sharing options...
hippy5488 Posted February 11, 2022 Share Posted February 11, 2022 top left would be the teflon seal ring between rear housing and top lift cover. if coming from up high. if coming from about third way down from top of housing could be lube line. either way most likely going to take pulling top cover to fix. should add before i get pummeled if its the lube line leaking it wont cause your current problem. but u just found a new problem Quote Link to comment Share on other sites More sharing options...
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