Altec AA755L Trouble

[psmith0803]

I'm having a bit of trouble with my Altec lift. I was using the lift had been working for about an hour and went to move the truck. I moved the selector valve from boom to out riggers and hard a pop and fluid running out the bottom of the machine. I shut down and figured out the return filter had blown it's seal. I replaced the filter added oil and ran the machine thru a few cycles of out riggers and boom and all seemed good. I took the machine to it's next job set up and worked about 30 minutes, moved worked about 20 minutes and went to move and while pulling up the out riggers it popped the filter again.

I don't see much in the hydraulic circuit when it's in "out rigger" mode that could cause an issue like this. I know the pump is variable so is it possible it's over driving the circuit ? Does anyone have any suggestions or a good altec service person I could call?

 

[Eq Broker]

You can call Altec at 1-877-462-5832.

Hope this helps!

Dave
Global Equipment Exporters
770-420-6400

 

[psmith0803]

Here is a response in case anyone stumbles onto this thread.

They claim it's an issue with the variable speed pump being spooled up to move the out riggers when you close the valve the pump is moving so much fluid it over whelms the filter and creates pressure which pops it. They say it's a known issue and the fix is to replace the stock filter/base with a filter/base that can flow 50 gpms and hold 150 psi. I can not find exactly what the stock filter would hold but I think it was 15 - 18 gpms (standard screw on hydraulic filter). The new filter/base is 100 bucks so I'm going to give that a try.

It's hard to imagine it's survived since 2006 without the fix but I got the impression if you feathered the valves carefully so it didn't create the surge you might be able to make it work.

Thanks!