Selectamatic linkage bounce

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

Selectamatic linkage bounce

Post by Richie » Wed Dec 19, 2018 5:49 pm

Hi guys, I’ve been reading this forum for a few years and am in awe of the knowledge you lot have. I have an 880 which I’m slowly getting working but on first examination I found no suction filter and knew it was going to spell major problems.anyway, I now have reduced problems to ghost lift on higher revs and bounce when raising to a stop, this can be stoped by screwing in the rate of lower nob a few turns, I also think I’m drawing in air on suction side( this improves on steep climb ) due to oil level probably. Do you guys think the air could be causing all the problems or just some? Hope you can help, cheers rich

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ollek
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Location: South West Finland

Re: Selectamatic linkage bounce

Post by ollek » Thu Dec 20, 2018 5:45 pm

Lets start with the possible air ingress into the hydraulic system as this can create all kinds of operating problems. The air can get in at the rear of the suction pipe. There is a brass connector stuck into the bottom of the suction pipe. This connector (ref 16) is secured with two bolts to the bottom face of the PTO housing. The connector has an O-ring (ref 13) at the top and air can get in if this O-ring is damaged or missing. There is also a O-ring (ref 11)between the rear end of the suction pipe and the bottom face of the hydraulic pump. Please see the following link https://partstore.caseih.com/us/parts-s ... 85ar285661 If any air has made its way into the lift cylinder, the this can be bleed out using the bleed nipple in front of the lift cylinder (ref 25), please see the following link https://partstore.caseih.com/us/parts-s ... 85ar321017

Richie
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Re: Selectamatic linkage bounce

Post by Richie » Thu Dec 20, 2018 7:38 pm

Hi ollek , thanks for reply , i assume the vacuum connector o ring would not be effected by oil levels? But the higher seals would i.e pump shaft seal would . . .?If I park on an incline and bleed ram cylinder everything seems almost as it should be except I need to lower revs for the arms to drop. I guess one problem at a time and I know I’m sucking air on level ground so il investigate that first . I appreciate your guidance. Richie

Richie
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Re: Selectamatic linkage bounce

Post by Richie » Thu Dec 20, 2018 7:45 pm

One more thing ollek , would you happen to know where the oil level naturally lies in relationship to the hydraulic pump ? I imagined the pump to be totally submerged but obviously not ! Thanks again Richie

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ollek
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Re: Selectamatic linkage bounce

Post by ollek » Fri Dec 21, 2018 5:47 am

The pump bottom is above the normal oil level oil level.

Richie
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Re: Selectamatic linkage bounce

Post by Richie » Fri Dec 21, 2018 4:49 pm

Thanks ollek.

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ollek
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Re: Selectamatic linkage bounce

Post by ollek » Fri Dec 21, 2018 5:27 pm

One more thing. A reliable hydraulic fault finding can not be made before the complete hydraulic system is free from air.

philedge
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Location: Chester UK

Re: Selectamatic linkage bounce

Post by philedge » Fri Dec 21, 2018 5:38 pm

Richie wrote:
Wed Dec 19, 2018 5:49 pm
I also think I’m drawing in air on suction side( this improves on steep climb ) due to oil level probably.
Not sure if Ive missed something, but if the oil level is low its probably best to fill to the top mark on the dip stick. If the oil is anything other than clean and clear probably best to change the oil with a gearbox flush before filling with fresh oil.

Did you replace the missing suction filter/strainer as not having this in place will raise the suction point slightly increasing the chance of drawing air in
'66 880 Selectamatic rat.

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

Re: Selectamatic linkage bounce

Post by Richie » Sat Dec 22, 2018 1:52 am

Hi philage, no I didn’t make it clear , I have flushed system , fitted new filter, purchased at great cost new strainer and refilled with fresh utto to top Mark on dipstick, il keep you guys posted. Thanks for your support in this difficult time ( English black humour ollek .

philedge
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Re: Selectamatic linkage bounce

Post by philedge » Sun Dec 23, 2018 7:20 am

Ok. If you think you are drawing air in, you could put a hose onto the rear camels hump tapping and run some oil into a clean bucket to see if theres air coming through with the oil. Dont let the gearbox oil level get too low before pouring the oil back in!!
'66 880 Selectamatic rat.

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

Re: Selectamatic linkage bounce

Post by Richie » Sun Dec 23, 2018 12:47 pm

Cheers philedge, spelt your name right this time, I have checked vacuum switch o ring , and that’s ok , I definitely make air at camels hump and obviously at lift ram nipple . 3 or 4 mins on a steep incline and much better so my gut feeling is maybe something quite high like the pump shaft seal. I don’t know if I said before but I have always conquered my dB problems (5 other dbs) from the back catalogue of this brilliant forum, guys like yourself and ollek the tractor Samaritans ! One thing; is there vacuum present at the pump output shaft seal? Looks like Christmas Eve in the cowshed, now where have I heard that before? You ollek and Erkki and I have my 3 wise men . Thanks again and merry Christmas. Rich

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ollek
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Re: Selectamatic linkage bounce

Post by ollek » Sun Dec 23, 2018 2:04 pm

Yes, the pump shaft seal is on the suction side of the pump. The shaft with the gear on is the pump input shaft (also called drive shaft), not output shaft and there is no output shaft on the pump. All hydraulic pumps with this designation have a shaft seal on the input shaft and this is on the suction side of the pump.-

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db2d
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Re: Selectamatic linkage bounce

Post by db2d » 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.

Richie
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Location: Uk

Re: Selectamatic linkage bounce

Post by Richie » Sun Dec 23, 2018 8:42 pm

Good info you guys, cheers. Rich

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

Re: Selectamatic linkage bounce

Post by philedge » Mon Dec 24, 2018 4:09 pm

Richie wrote:
Sun Dec 23, 2018 12:47 pm
Looks like Christmas Eve in the cowshed, now where have I heard that before? You ollek and Erkki and I have my 3 wise men . Thanks again and merry Christmas. Rich
Happy to help where I can but my DB knowledge is relatively limited and theres lots of members far more deserving of the wise man badge than me. Have a good xmas yourself.
'66 880 Selectamatic rat.

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