I have a caterpillar 267b which is starting to hesitate when going from forward to reverse or reverse to forward. It may take two to three seconds for it to respond. Wagner equipment of course wants to replace everything from the pilot valve to the shuttle valve. I don't think it is that serious of a problem and I have never been one to change everything to find the problem. None of their mechanics seems to know what to do but replace everything. Anyone had this problem?
Yes, it is inherent in the pilot valve machining....we are talking thousandths of an inch. I had a 246B that hesitated to go right. The easiest way to test and check is to swap the hoses from the right pilot (loader) to the left (drive). then you can know for sure that its a pilot problem not the forward reverse control valve. The have a delay built in but every B series machine I have operated has been slightly different. Your dealer knows that changing the pilot valve is like a 20 minute job...whereas stripping the pilot and playing trial & error with chart paper or copper shims can take forever. Trust me on that one. A Cat mechanic who knows his stuff will swap those pilots left for right in no time.
What is it in the pilot valve that makes it hesitate? What do the shims do? Thanks
More than likely its the machining...but I'm really only guessing. Shimming changes the angle of the pilot in the seat. Don't pull a pilot valve body apart unless you know what you are doing.