Last week,i sent my pump to my hydrolic guy to change the shaft seal on two hydrolic pumps and the packing seal on both concrete cylindres.Since that day ,it has been a week,7-8 jobs,200 meters pumped and my schwing 36m 1200 1997 isn t the same.

First the pump seems to work twice has hard to pump pretty easy mix.trouble restart between trucks.

Secondly,the pump speed his not very accurate.i mean ,i adjust the speed controle on the remote at maybe 6-7 it will pump wide open so i slow it down but nothing happen until i have done maybe half a turn on the controle.Then it much too slow !So slowly i open it gradualy nothing happen and then bang wide open again after a half turn or more on the controle.Also ,when i stop and restart to pump,the pumping speed is not the same.On my remote and on the rear panel.It s never been like that before

Third,i know that when you on fold a boom it can bounce a little but man it s very scary.

I feel like hydro pressure out off the pumps is not the same but hydro guy told me that he took off the two hydropump that were leaking and changed the shaft seal ,put it back.He tough that he would have titghen the packing seal cover in the water box too much, so he loose them.Nothing better.

Is there any relation between hydropump and maybe some of the troubles i got

Thanks everyone

Very confused ti-so

I borrowed my friends 36m for tomorrow i have 120m³ footing and i don t want to take anychances.

We had a similar problem with our 36 it turned out to be the flow control solanoid.

It would pay to check the spacing on your packing seals as either to tight or to loose can cause damage to the crome rod, your service manual should have the correct spacings and formula to work out  the correct amount of shims required. If not ive got a copy in the office i can email you.

Did you use schwing parts?

the packing are schwing and the schaft seal are rexroth or something like it for the rest schwing

??

On your chevron seals you are to have 1mm crush. Were there shims on your tension rings? I have never seen it but have been told if there is to much crush the seals can peal the chrome off. For your shaft seal on your pumps most guys drive them on to far. You onlt put them in far enough to put your snap ring back in. its a face seal not a shaft seal. hope this helps you.