Our 06 th460b was starting to get hard to start about a month ago. It was turning over too slow. The batteries being 7 years old I thought just change the batteries. This didn't help, so I called our local cat dealer and they sent out a tech to change the fuel filter and he suggested a new starter. he changed the starter but this didn't help either so he called tech support . They told him to crank the steering wheel while turning it over and if it sped up then the priority valve that supplies hydraulic power to the steering and brakes was blocked. It did speed up the cranking so he ordered a new one and installed it. It is still not starting like it was. Our machine has 2300 hour on it. We are 3 grand in and the cat boys are still scratching their heads. Anyone will the same or similar machine had this happen. thanks
Why are you 3k into it with CAT if its not fixed?! It sounds like they are shotgun troubleshooting and charging you for it?! I wouldn't be paying!
I forgot to mention they also changed all the hydraulic fluid and the filter. The priority valve is in the hydraulic system which is also the transmission fluid as well.
We had one years ago doing this. We found a valve in the system that had backed out. Couldn't say where it was though.
Did anybody check the grounds?
The tech tested the amperage at the starter as we tried it. It came up what it should read getting to the starter. He thought he had it figured out with the priority valve. Also he suspected possible contamination in the hydraulic fluid so he changed all the fluids and filter.
Heres an update to our problem. Had the cat tech out today again. The machine has not been starting well since we had it fixed. The priority valve that we changed earlier was still the suspect. The tech brought back our old valve that he had cleaned. After testing the batteries again which are new, we decided to put the old valve back in. It started right up. We are guessing that the hydraulic fluid which is also the tranny fluid has some contamination in it that keeps clogging the priority valve. So it is fixed for the moment. We have the new valve which we will clean and keep handy in case it clogs again. This machine only has 2100 hrs on it. The tech said that because we had not changed the hydraulic fluid regularly particles have contaminated the system. We changed the filter again and will be more diligent about changing our fluids more regular. Hope this solves our problem but is a lesson on preventative maintenance. Just because it doesn't have a lot of hours doesn't mean you can get away with not changing the fluids regularly. Thanks for everyones input.
Cat offers a lower micron filter as well or clean out filter. The main control valve is real sensitive as well. I have had to replace several of them at $3000 a piece. It has been updated now so you can get it with individual solenoids but the updated one is still $2700 for the valve.
Hey friend, was reading threw here an saw ur issues with the th 460, im very familiar with him, I worked at a cat dealor for bout 7 yrs, if the cat guys are telling you that you have dirty oil in ur systems due to lack of serviceing properly, an you say you keep changing ur hyd filters out an its not helping ur problems due to the whole hyd system,,,,now I nay be wrong but I don't think that the trains. fluid an hyd. fluid are in the same system as each other,,, I remember that the trains. has its own dipstich there behind the batteries, but either way it ur cat guys are telling you that ur oil is dirty WHY HAVENT THEY MENTIONED PUTTING UR MACHINE ON THE FILTER CART don't mean to sound like im yelling at ya but I worked at cat for yrs an they use to run the cart on machines all the time to filter the oils to get the particle count down, the paticle count is the dust like trash in the oil that ya cant see with just ur eyes alone, the filter cart is amazeing ,, its locks like the big propane tank out in ur back yard that hase big filters in it to cat the particles an returns cleaner oil back into ur system, it has hoses that ties into ur machine while ur machine sits there an idles for few hrs then the tech takes an oil sample an runs it threw a machine an it tests cleanliness,,,,,,just like a DNA lab does,,,, it ll even tell ya if you have a lot of a certain type metal in the oil that's not suppose to be there (basicly tells you if ya have bearing wear going on or if maybe coolant is starting to leak into that particular system) kinda help with preventive down the road break down, but back to the filter cart each machine has its on standards to meet for cleanliness an after running the cart for few hrs an he checks the micron readings if its now in spces he changes the filter cart filters an tractor filters an runs it again, sometimes a all day thing but it will eventualy get the oil clean. as the cat guys bout the cart. they have to have one for there warranty reasons an to save there own buts down the road.
Thanks for the tip guys. I will ask about them next time I see the tech.
Just curios where this valve is located. I have the same machine and it starts slow but it starts even when really cold out. When I got it it only had one battery. I added another but it didnt really seem like it helped all that much. I'd like to check this valve out on my machine. Thanks
Just another update. Don't know for sure if this is related but the last couple months the machine had started to lack power and of course was hard to start. Yesterday the fuel pump gave up the ghost. We replaced the fuel pump and what do you know, its starts like it used to. Just a guess as I am no mechanic, but maybe the fuel pump was slowly dying and the hard starting was an indicator of that. Anyway happy to report it is finally starting like it used to. Cheers
Is that the black cartridge type fuel pump with filter built in with electric motor?
yes. the pump is on top of the filter canister. All one piece.
Sorry to read the thread too late!! As soon as I started reading I suspected that pump! These are hand overs from perkins, and the cause a whole lot of trouble, from engines hunting to dieing underload to not starting at all. We carry a spare pump in the truck at all times. Just fail for no reason at all, no matter how often you change the filter. There is an upgrade kit to replace the pump with a silver bullet style pump, but I think it's quite expensive. Are you going to try to get some back from the cat dealer, lot of effort for what should have been a simple fix
Got a cat th460 B new battery new starter cleaned and replaced priority valve left it out to try and get cranking speed with no luck I also disconnected the hydraulic pump and it still won't crank over fast enough new fuel pump ! Has one cylinder lower than others on compression but it ran fine and quit one day and it hasn't started since any ideas or thoughts will be greatly appreciated thanks.
U have one or two batterie? They require 2
It looks like it's only wired for 1 battery but I'll wire it for 2
Yes there’s a spot for two group 31’s. One if them is a biatch to get in there lol