CAT 345BL slow Dipper Stick slow Retract Motion

[overworked]

Why did it not changed when thy switched the hoses on the cyl. ?

 

[Maurice Muenks]

Depending on where you swap the hoses at you might have a bad hose on the inside. May have swallowed it's tongue. You sure have a good one there! Will be interested in what you find.

 

[gannaly]

And how about the regen spool, checked the seals on that yet? i'm willing to bet some money on it.

Now, it is time to check, rest of the systems were checked, nothing has been found yet...will check the regen spool soon, slowly coming down to the root

 

[gannaly]

Why did it not changed when thy switched the hoses on the cyl. ?

Yes, exactly this is the question everyone is concerned actually Looks like this is an odd issue though

 

[gannaly]

Depending on where you swap the hoses at you might have a bad hose on the inside. May have swallowed it's tongue. You sure have a good one there! Will be interested in what you find.

We swapped the hoses on cylinder end. Hoses have been checked separately, both of them are good, no obstruction inside.

 

[gannaly]

grannaly take the long tube off of the cylinder and check it for obstructions.
Later Bob

Bob, we checked it, clean

 

[overworked]

I think you are not getting both pumps to upstroke when swinging stick out. Its fast when gravity is helping bucket away from cab but when you go over center only one pump is filling cyl.

 

[gannaly]

Gents,
We have checked the regeneration valve, all the seals were extremely damaged, no sealing function was in place. I will post the pics tomorrow.
Thanks Per, we are not 100% sure yet but looks like this is the root cause for the issue. After installing redressed regen valve and cylinder, we will check the machine functionality and update this thread.
By the way, we saw that there were some tiny metal particles inside the valve, does these metals make the seals worn out? and is there a best practical way to clean the whole hydraulics system from these particles?

 

[Per Eriksson]

I don't think it's related.

Replace filters, make sure tank is clean and if you have one, run a kidney loop.

 

[tctractors]

gannaly, the regeneration valve is common to be called the recycleing valve (spelling ???) in the U.K. it is a bit of a pig to strip out due to the oil dripping all over you as things come loose, credit to Per Eriksson for chiming in at the start pointing you to this valve that often thows up some very odd antics with the front end activity, anyhow things should be better now with a few penny 0 rings etc stuffed on to the shiny bit with groves, to do a half good job on the hydraulic tank and oil clean up, I use my kidney pump to pump out the hydo oil into clean barrels or I.B.C. container, then do all the filter and tank cleaning dutys, finaly pumping the oil back into the tank useing the kidney pump, so the oil has been filtered out and then back into the tank so things start off from a good point, oh and just a point, the spool springs are under the top cap, remove this cap and the spools lifts out,

tctractors

 

[gannaly]

We have tested the machine after installing the regen back with o-rings dressed. Unfortunately, issue has not been solved yet. Old o-rings on regen valve were completely worn out, there was no any o-ring in place but only tiny hardened o-ring particles instead. That's why, may these old o-ring particles spread over in a hydraulics system blocking the flow to the stick? If yes, where should be the first place to be checked?

 

[Construct'O]

You would want to start by tracking the lines down stream from the regen valve,and anything going to the slow moving cylinder.Had this happen on a trencher and the hydraulic tank was full of packings and the suction screen was covered with packing restricting the flow.The hydraulics run hot because of this.Good luck.

 

[Nige]

Based on the reply above why not pull the suction screen out of the tank and check it as a first step ..? It's easy enough to access.

 

[overworked]

Can you cap off pilots and run stick from one pump at a time, that might isolate it to one section.

 

[Per Eriksson]

Does it track straight?

 

[Per Eriksson]

Any update?

 

[gannaly]

Sorry guys. Due to the weather condition, we are currently stand by. We will update once we again start trobleshooting.
Yes, it does track straight, no problems with tracking. We are planning to check 2nd pump's connecting spool for stick.

 

[Mobiltech]

I have seen a lot of the regen valves fail. There was a service letter on them from Cat for the 345. Rather than resealing I would replace both. They will seal ok with no load but when loaded they leak which shows up after the downward travel of the stick.
I can't explain why swapping hoses didn't work but the regen valves do connect both ports in regen mode.

When you had the cylinder apart did you pull the nylon seal out on the piston and check the oring underneath it. Sometimes that oring can fail without showing signs on the outer nylon seal.

 

[Bob/Ont]

If what you tell me about swapping lines and the problem staying the same is correct, I will repeat myself once more. " Check the Cylinder or get it rebuilt" you are missing something.
Later Bob