Linkage not lifting fully and dropping under load

[agroman]

Hi all, it's been a long time since I was last on this forum - apologies! In my defence I have a couple of Landrovers and they take up most of my forum time allowance!
The dexta on the other hand has been pretty much trouble free since her rebuilt 3 years ago. Now she needs some TLC again!

During my 2017 hay making campaign the linkage as stopped raising to the top. I am assuming it is ware on the position pin again, so will take top off and have a look. See previous post, I had been using the loader with draft lever in position control which has probably lead to premature ware of the pin!

Also when the diverter is pulled out for external services (loader) the link arms are now dropping a bit too quickly. I use a weight on the linkage with loader, so it is a pain to have to stop every few minutes, alter the plunger and raise the linkage again, gets worse as the oil gets hotter obviously. When I 1st rebuilt the cover etc. The linkage would stay in position for a long time, almost overnight. So something has worn over the last 3 years.

Am I looking at the main lift ram seal / cylinder or should I be also looking at something else?

[MikesDexta]

I take it you have checked the oil level in the rear axle? It surprised me how much you can lose over a season if a rear axle seal is leaking for instance, and I had problems similar to yours. Mike

[agroman]

Oil level fine, a little over full if anything as I had put a jug full in in the vain hope that this might help.
Took top off and position pin is worn nearly half way through - so this is my lift height problem. Welded up the grove and ground it back to shape, easier than replacing the pin!

Everything else appears ok. So I have honed the bore of the lift cylinder and will replace all the seals including hydraulic piston lip seal. I have had a problem with the ASV plunger getting very stiff so that it can only be pulled out with a pair of vice grips. I mounted the plunger in electric drill chuck with drill in vice and used some 2000grade wet n dry to polish the surfaces. This appears to have made the plunger easier to operate. With regards to the top plate of the ASV block, I did have a gasket in there as Agriline supply one. But looking at the parts diagram there isn't one. So I will refit without one and with new o rings this may help squeeze the o rings a touch tighter?

Just waiting for seals to arrive from Agriline, but it is a bank holiday and I think couriers are reluctant to come to the Westcountry on a Friday, so it will have to wait until next week.

[agroman]

Ahah seals arrived today in the post, so able to get on with the rebuild. All back together. Lift height is fine now position pin is rebuilt.

The auxiliary service block does need the gasket in place otherwise it leaks oil. So refitted with gasket. Linkage arms still dropping as soon as the auxiliary service spool is pulled out. With it in, the arms are good and static even with engine off. I have found that if the service valve spool is not pulled completely out against the stop grub screw then the lift arms don't drop. So my next experiment is to try placing some washers between the grub screw and the shoulder of the spool valve to reduce its' travel. I think it needs to be about 6mm, so that linkage doesn't drop but loader will still work.

Will update when I have a chance to try this out.

[agroman]

I have put a few copper washers between the shoulder of the spool valve plunger and the grub screw stop to reduce the valve's movement outwards when selecting auxiliary operation. This works a treat, needed about 5mm. The auxiliary i.e. loader is also working fine with the draft lever dropped into draft position. So all good! Next job is moving of my various dung heaps when I get time, hopefully with the help of a mates Super Major for dung spread / trailer duties!

[MikesDexta]

I can't see you photos - just an error message?

[agroman]

Photos were originally uploaded from Photobucket. They have recently requested a large charge for photo sharing and have locked out all pictures until people pay up!
Not willing to do this so need to find a new file sharing site for my photos.

What site are others using?