Selectamatic linkage bounce

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Amended 27/10/18

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Richie
Posts: 40
Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Mon Dec 24, 2018 5:43 pm

Hi guys, I have removed the p t o box and loosened the suction pipe, the o ring was pretty hard and had flats on it , I flexed it and it snapped so I think that maybe the culprit. Would you experienced guys change the pump shaft seal while apart ? I have also fitted a vapormatic suction filter, has anyone had problems with the o ring staying in correctly? I’m a time served fitter but these filters can be a pain. Is there a better pattern part. I have removed the spring washer so the spigot sits in a little further. Such an important connection should be idiot proof. Is it possible to remove the suction pipe completely without removing the rear bellhousing or is it a big job ? I’m considering popping her back together to see if cured as it’s relatively simple. Cheers rich

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ollek
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Location: South West Finland

Re: Selectamatic linkage bounce

Post by ollek » Mon Dec 24, 2018 6:26 pm

Some of the suction filters and other parts on the market are of dubious quality. For a filter or other parts that fits, contact Peter Williams, see the following link http://www.davidbrownparts.com/ The removal of the suction pipe is not that simple, it can involve removing the complete rear axle.

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db2d
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Location: Monmouthshire

Re: Selectamatic linkage bounce

Post by db2d » Mon Dec 24, 2018 8:24 pm

I would not recommend resealing the pump at this stage. Have you carried out the simple test I mentioned earlier?

Richie
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Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Mon Dec 24, 2018 8:47 pm

Thanks for that link ollek, and to reply to db2d yes , I did carry out the incline test earlier in this thread and after a short bleed the system did return to almost perfect except for ghost lift at high revs and I had to reduce revs to lower arms but these may be unrelated problems? Ollek wisely suggested sorting air problems first and then re assessing the situation. Remember this tractor had been used with no suction filter so I could have foreign bodies in valve chest or pump damage.i think il replace suction pipe o ring and give it a try . Thanks again rich

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ollek
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Re: Selectamatic linkage bounce

Post by ollek » Tue Dec 25, 2018 8:08 am

You will get ghost lift if the small hole in the restrictor washer (ref 3) in the by-pass valve has been made bigger or the washer is missing or the brass plug (ref 4) is not tightened properly. Please see the following link https://partstore.caseih.com/us/parts-s ... 85ar297525 Some individuals think it is a good idea to make the hole bigger end thereby stropping dirt coming from the transmission housing, plugging the hole, resulting in no lift. It can not work and the result of this interfere is ghost lift.

Richie
Posts: 40
Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Tue Dec 25, 2018 9:02 am

I’m hoping the air problems may have contributed to the ghost lift? I also remember once placing a small o ring under the restricor plate to improve the seal as the small filter had been damaged and I guess this was a sort of gasket in the design theory? That was on my 990 , can’t remember if it helped but it’s good to explore. Thanks ollek. Rich

Richie
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Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Thu Dec 27, 2018 4:57 pm

Hi guys, fitted a new suction pipe o ring and re assembled, the hydraulics were instantly sorted , all the symptoms are sorted except the linkage is slow to drop on high revs? Is this typical of an old 880 or do I need to have a look at that ? Many thanks to all who helped and as ollek said ( any air in system will cause all sorts of weird symptoms) don’t go chasing rainbows like me ! Cheers rich

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db2d
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Re: Selectamatic linkage bounce

Post by db2d » Thu Dec 27, 2018 5:32 pm

db2d wrote:
Sun Dec 23, 2018 3:38 pm
Fill the gearbox to just above the maximum mark with the tractor level and then park nose up on the steepest incline possible and work the hydraulics. The fault you described is usually the seals on the induction tube.
This simple test procedure eliminates air being drawn into the pump from a faulty seal on the induction pipe.

philedge
Posts: 236
Joined: Sun Dec 03, 2006 11:27 am
Location: Chester UK

Re: Selectamatic linkage bounce

Post by philedge » Thu Dec 27, 2018 6:54 pm

Richie wrote:
Thu Dec 27, 2018 4:57 pm
Hi guys, fitted a new suction pipe o ring and re assembled, the hydraulics were instantly sorted , all the symptoms are sorted except the linkage is slow to drop on high revs? Is this typical of an old 880 or do I need to have a look at that ? Many thanks to all who helped and as ollek said ( any air in system will cause all sorts of weird symptoms) don’t go chasing rainbows like me ! Cheers rich
Great result. Did you need to do anything obscure to access the pipe/o ring, or was it quite straight forward?
'66 880 Selectamatic rat.

Richie
Posts: 40
Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Fri Dec 28, 2018 10:07 am

Hi philedge, the o ring is easily fitted at pump end and some other info that the less experienced may find helpful is when you fit the suction filter keep its o ring and o ring recess clean and oil free, place a clean smear of grease up into the suction tube location and the prevents the o ring being displaced when you push it up . It’s obvious when it pops up correctly and if it’s resistant up to its stop then it’s probably dragged the o ring askew.hope this doesn’t sound to patronising but it is an important seal that is not the best design . Cheers rich

Richie
Posts: 40
Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Fri Dec 28, 2018 5:44 pm

I’m still struggling with the ghost lift at higher revs , I don’t seem to have the small screen filter below the restrictor plate and am wondering if the plug may run out of thread before it fully pinches the restrictor or the hole has been enlarged very slightly. As with carburettor jets can poking wire through orafice cause enough to be a problem? Hopefully I can buy thes parts from the link ollek sent me to eliminate them as my cause . If anyone has any other suggestions I’d appreciate it. Cheers rich

Richie
Posts: 40
Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Fri Jan 04, 2019 8:47 am

Hi everyone, the current state of hydraulic system is dramatically better than when I started , the suction pipe seal at pump end was replaced and was instantly free of pulsing bounce.however, on trials I came down a moderate slope and air re entered causing loss of lift . On returning to level ground the operation returned to normal . I didn’t interfere with the pump when fitting the suction o ring so I guess I should next fit a new shaft seal ? Is overhauling the pump straight forward as I’ve read it can be problematic? Cheers rich

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db2d
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Location: Monmouthshire

Re: Selectamatic linkage bounce

Post by db2d » Fri Jan 04, 2019 10:19 am

I would be surprised if it is the pump. I suspect there is something still not right on the induction pipe. Check the switch sealing on the under side of the induction pipe.

Richie
Posts: 40
Joined: Tue Dec 18, 2018 7:13 pm
Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Fri Jan 04, 2019 11:54 am

I’m with you db2d, I’m reluctant to split pump, I have replaced the vacuum switch o ring . Ollek kindly informed me that the suction pipe itself can be a lot of work To remove so my only other simple replacement is the pump shaft seal which I assume is replaceable by removing the drive gear? Does anyone know of a pictorial which shows oil level through transmission in relation to the hydraulic pump ? It would be interesting and maybe a diagnostic help to know the height of possible air ingress weak spots . Cheers rich

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db2d
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Location: Monmouthshire

Re: Selectamatic linkage bounce

Post by db2d » Fri Jan 04, 2019 3:41 pm

If the system works when the tractor is level it is not the pump seals. Are you certain you have the correct size ‘O ‘ rings on the induction pipeline?

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