DB 990A Implematic Hydraulics Not Working

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ollek
Posts: 3924
Joined: Tue Apr 10, 2012 1:20 pm
Location: South West Finland

Re: DB 990A Implematic Hydraulics Not Working

Post by ollek » Sat Dec 14, 2019 8:40 am

I would not recommend to put any "conditioners" or cemicals into the gear box oil. All modern oils have all additives needed for the oil to perform in the correct way. The way you keep water out of the oil is simple, cover the tractor so that rain can not get in and change the oil and clean the intake screen at the intervals stipulated by the manufacturer.

blissakpo
Posts: 76
Joined: Tue Jul 17, 2018 7:15 pm
Location: IRAQ

Re: DB 990A Implematic Hydraulics Not Working

Post by blissakpo » Sat Dec 14, 2019 7:10 pm

Just to add one small point to the comment db2d made regarding the main control lever connecting to a small push rod giving lift hold and drop - It does, and is located directly under the control lever acting on a cam inside the back axle - This as he said controls the up/down of the 3 point lift. There is a spring on it externally mounted held in place with a circlip, when you push the control lever forward the 3 point lift drops and when you pull back the spring pulls the rod off the cam and the 3 point rises. It is not unknown for the circlip to ping off and the spring to be lost - Then when you pull back the control lever the implement will not rise. Those not in the know eventually work out that the lever arrangement inside the control box does not actually work the up/down function and seeing the pushrod stuck in assume that is the problem and give it a whack with a hammer assuming the spring is internal to free it off - all this does is ensure the pushrod overrides the cam and you have to take most of the back end apart to rectify the situation. It is possible to pull the pushrod out install a new spring and using a thin piece of plastic or simular with a hole drilled in it to compress the spring reinstall the circlip without having to take all the back end to bits and save yourself hours of work in the process if you are aware of the problem and forgo the bit with the hammer. By the way the pushrod has a pointed end machined on it where it acts on the cam, during operation the pushrod rotates so you get even wear but eventually the end wears out - Replacement pushrods are available from Barclay Williams in the UK should you ever need one.- Just saying. Andy

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db2d
Posts: 2172
Joined: Fri Feb 24, 2012 10:01 pm
Location: Monmouthshire

Re: DB 990A Implematic Hydraulics Not Working

Post by db2d » Sat Dec 14, 2019 8:59 pm

It is important that the hydraulic control linkages are correctly adjusted to avoid damaging the pushrod. The spring can be retained with either a circlip or an e-clip but the best option is to drill a hole and use a split pin.
Incidentally, without going into details this pushrod assembly can be changed without removing the hydraulic cross shaft etc.
These parts are also available as a kit from davidbrownparts.com

LoneWolfMuskoka
Posts: 22
Joined: Sun Sep 15, 2019 3:18 am
Location: Canada

Re: DB 990A Implematic Hydraulics Not Working

Post by LoneWolfMuskoka » Sat Jan 04, 2020 7:38 pm

Thank you for the tips on the pushrods. I'm having trouble with the actual control arm as the bottom piece which holds the adjusting screw for the pushrod under it has snapped off. The previous owner put the wrong bolt in there (UNC rather than the BFT or BWT that likely requires). I applied a little too much force trying to remove it and now I'm working on replacing it. The pushrods both seem to be working fine so I should have control back once I can get that all sorted out.

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ollek
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Joined: Tue Apr 10, 2012 1:20 pm
Location: South West Finland

Re: DB 990A Implematic Hydraulics Not Working

Post by ollek » Sun Jan 05, 2020 2:17 pm

You wrote "UNC rather than the BFT or BWT that likely requires)". There is no thread called BFT or BWT. The thread on the screw and the lock nut is BSF (British Standard Fine). Please see the following link https://partstore.caseih.com/us/parts-s ... 2ar1079720

LoneWolfMuskoka
Posts: 22
Joined: Sun Sep 15, 2019 3:18 am
Location: Canada

Re: DB 990A Implematic Hydraulics Not Working

Post by LoneWolfMuskoka » Sun Jan 05, 2020 8:53 pm

Thanks for the correction ollek. I'm just learning about the different thread standards and I knew it was British and Fine. And the other standard is Whitworth or something like that.

Are they very common still in the UK? Or are the metric standards more common? Here in Canada the universal are still most common but metric is catching up.

Gard
Posts: 278
Joined: Sun Apr 06, 2008 2:25 pm
Location: Fairfax Vermont USA

Re: DB 990A Implematic Hydraulics Not Working

Post by Gard » Sun Jan 05, 2020 11:49 pm

I would be surprised to find BSF whitworth bolts or wrenches at the local hardware store but are easy to find on the internet, in the US, I have had good luck with britishfastners.com

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cobbadog
Posts: 735
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: DB 990A Implematic Hydraulics Not Working

Post by cobbadog » Mon Jan 06, 2020 10:26 am

BSF = British Standard Fine.
BSW = British Standard Whitworth. Both are Whitworth threads and nuts and bolts can still be purchased but are expensive to buy here in Australia So I bought a small lathe to make ones myself.
As for spanners, these are still available online and most are made in India. Surprisingly they are pretty good quality. I have many taps and dies to clean up both thread pitches and a sockets, combination spanners and ring spanners to ensure I have the right size spanner for the job.

Gard
Posts: 278
Joined: Sun Apr 06, 2008 2:25 pm
Location: Fairfax Vermont USA

Re: DB 990A Implematic Hydraulics Not Working

Post by Gard » Mon Jan 06, 2020 11:36 pm

I looked at my 990 implematic and found the "grub screw" part #3 on the Case IH parts page is a 5/16 BSF bolt, 1.5" long that appears to be threaded full length. The head of the bolt bears on the plunger part #6. There is a lock nut on the front side of the lever.
I looked on the brittishfasteners.com web site and it appears their BSF 5/16 x 1 1/2 bolt is not fully threaded, cost is only us$ 1.15
If you contact them they may be able to provide a fully threaded version or they sell a die you could do it with for $15.
Another option would be the fully threaded cheesehead screw, 2" long for $1.55. You will also need nuts and perhaps a tap to clean up the threads, $ 7.26.
I have been happy with this company but have no affiliation with them, I am sure there are others on the web.

I also noticed the spring #7 is in place but plunger is missing the retaining snap ring.

LoneWolfMuskoka
Posts: 22
Joined: Sun Sep 15, 2019 3:18 am
Location: Canada

Re: DB 990A Implematic Hydraulics Not Working

Post by LoneWolfMuskoka » Mon Jan 13, 2020 4:26 pm

Thanks for the updates on BSW and BSF!

For my control arm, the part at the bottom that the "grub screw" goes into completely snapped off when I was trying to get the stuck bolt out. So I've attached a long nut (not sure what the term is, but that's how I view it 8=) with JB Weld. I'm using a threaded rod to replace the grub screw and it's working so far. Hopefully it will last me until spring time and I can afford to have the controls apart for a couple weeks to work on them more and have a proper weld done (or replace it).

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