cat 305E no Hydraulics

[jbernielh]

got a call from a friend today with a 305.. I've got a 304.. same manuals.. machine was running fine and then it was like the safety bar was raised.. zero function on any hydraulic system.. engine dropped to idle as it would in a non demand situation and stayed there..
he said he jumped the micro on the safety bar and that had zero effect..
he doesn't have any pressure gauges to take readings from the test ports..
hydraulic levels are good and no leaks anywhere
I gather there was no slow loss of function, it was immediate and includes tracks as well as bucket, boom and swing..

I'll probably take a drive there tomorrow with my test gauges and manuals but thought I'd check here tonight and see if anyone has had a similar situation or thoughts on what should be looked at..
I don't have his serial number

Bernie

 

[lantraxco]

My first guess would be the coupler on the back of the flywheel, I believe it's a flex plate with a splined center, they sometimes just strip out.

 

[jbernielh]

I find out now that there was a burning rubber smell prior to so I suspect that your right..
Guess the next question will be if there’s a pump issue that caused it

 

[lantraxco]

Probably just hours, but you never know.

 

[jbernielh]

They’re pulling the pump now.. I think they’ve found a shop that can test it (if it isn’t seized)
The next trick is if the coupler can be replaced without pulling the bell housing... doesn’t look like it in the parts manual

 

[lantraxco]

Should just be a cover plate....

 

[jbernielh]

the coupler was toast.. the hydraulic pump appears okay.. the bell housing did need to come off to replace the coupler..

 

[lantraxco]

cool... all good news except the last part, eh?

 

[jbernielh]

all good
no dirt under my fingernails..
I was just playing tech support..