Cat 305CR stick control problem

[Phil_C]

Hello All
Yesterday when using my 305CR's stick in function it started stopping and starting and did this for about ten minutes before returning to normal operation. Today it ran fine for about half an hour before it started doing the same thing only after a few minutes it stopped working at all. I parked the machine and looked around for a leak or blown hose in the control circuit but could not find any.
I am guessing it is a problem with the pilot operated control valve but before I start pulling the machine apart to get to the valve is there anything else that could cause this issue? No other function is affected only the stick in. When using the function the engine loads up slightly so I assume the hand control valve is supplying pilot oil to the valve.
Serial CAT00305VDGT01480

Regards

Phil

 

[Phil_C]

Well despite my earlier assessment it is the hand control valve that is faulty. I ran the machine today and it worked for about half an hour. Once it started playing up I swapped the control configuration and the problem went from the stick to the main boom thus eliminating the main DCV. I have removed the left hand control valve. Does anyone have an exploded view of the valve preferably one that shows how it is assembled? The parts book only shows a part number for a complete valve which is $2041 AUD.

 

[Nige]

What Part Number of pilot valve are you looking at..? All the ones I can see have full breakdowns available but I may be looking in the wrong place.
Identifying which valve it is might well lead to a Disassembly & Assembly procedure.

 

[Phil_C]

248-0100 is the number for the complete control and 249-4745 is the actual pilot valve. My parts manual only shows a cut away of the control but not an exploded or detailed listing of the parts in the pilot valve.

 

[Nige]

Is yours a Cat Parts Manual.?
The online version shows the illustration below. All the items with numbers associated are available as spare parts in addition to the complete valve that you already know about.

 

[Phil_C]

Hello Nige
Thanks for the image. I have the genuine Cat parts book. I found the illustration that you posted above. I only found it by looking for the part number in the list at the back of the book.
I pulled the valve out and dismantled it but I cannot see anything wrong with it. I was hoping to find a broken spring or a badly damaged seat but it all looks good. The only other thing I can think of is that there is a crack in the valve housing that is opening up when the machine is at working temperature. My next step is to reassemble the valve and refit it and run it till it plays up again and do some tests.

 

[Dale Beeson]

Is yours a Cat Parts Manual.?
The online version shows the illustration below. All the items with numbers associated are available as spare parts in addition to the complete valve that you already know about.
View attachment 202103

You don't by chance have the hydraulic line input designations for the bottom (right side)

 

[Nige]

You don't by chance have the hydraulic line input designations for the bottom (right side)

Replied to your question on the thread you created.
The poster above has a different model of 305 (DGT vs DCR) with a different Part Number of pilot control valve to the one you have.

 

[Dale Beeson]

Sorry to jump back and forth between posts but Is the DGT series older or newer than my DSA?

 

[Nige]

Sorry to jump back and forth between posts but Is the DGT series older or newer than my DSA?

3 years newer. 2005 vs 2002.
Also could have even been manufactured in different countries.