does shear cyl have regen valve, ussualy regen valve instaled on lines boom and stick, i read your firt post that you have replace relieve valve, just make sure that is for rod end or head end ? And did you have adjust this valve ? The Spec about 5050 psi
-
Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!
Cat 345B losing hydraulic pressure in one ciruit as it warms up.
- Thread starter Scrapper
- Start date
Per Eriksson
Senior Member
This one, 
I took the regen valve out. I don't see any seals on this thing at all. I also noticed some scratches on it that I took a picture of. Can you let me know if there is supposed to be seals on this or not and if you think the valve is salvageable or if I should just buy a new one.
Also if anyone has a parts breakdown of the valve I would really appreciate it. I can PM you my Email address if you need it.
Also if anyone has a parts breakdown of the valve I would really appreciate it. I can PM you my Email address if you need it.
Per Eriksson
Senior Member
There you have it, you should have seals in all five grooves.....
I wouldn't worry about the marks since they are on the outside and don't have anything moving against them, just try to smoothen them out a little so you dont damage the seals when putting them on.
Make sure the spool fits nicely in the bore and moves freely.
Parts breakdown View attachment Regen valve.pdf
The updated replacement version that have better seals, pricy but you could get just the updated seals.
View attachment Regen valve updated.pdf
I wouldn't worry about the marks since they are on the outside and don't have anything moving against them, just try to smoothen them out a little so you dont damage the seals when putting them on.
Make sure the spool fits nicely in the bore and moves freely.
Parts breakdown View attachment Regen valve.pdf
The updated replacement version that have better seals, pricy but you could get just the updated seals.
View attachment Regen valve updated.pdf
Last edited:
I don't think you would be able to post if you didn't activate your account. Not sure why you wouldn't be able to start a new thread. I believe I started my first thread right out of the gate with no post count when I had a problem with my EX400. Some forums require you to have a certain number of posts before being able to do certain things on the forum. That might have been changed since I joined too and was the reason I could start a new thread and you can't.
You might want to go ahead and create a new account with a different Email address and see if that fixes your problem. You can make up a new Email pretty easy using Hotmail or Gmail. Good Luck.
You might want to go ahead and create a new account with a different Email address and see if that fixes your problem. You can make up a new Email pretty easy using Hotmail or Gmail. Good Luck.
Thanks Per Eriksson for the help and the parts breakdown.
That is really something that all five of the seals were completely gone. I can see how oil could go from one port to another and mess this thing up with no seals.
The spool moves freely inside the bore and the spring is not broken so hopefully it will be alright. I'll take some emery cloth and smooth out the scratches before installing the new seals. I have five new seals on the way from the dealer, $3.00 each for the seals plus shipping, should have them on Tuesday morning. The new replacement valve would be just under $500.00.
I will let you all know how it turns out once I get the valve reinstalled back in the machine, hopefully on Tuesday.
That is really something that all five of the seals were completely gone. I can see how oil could go from one port to another and mess this thing up with no seals.
The spool moves freely inside the bore and the spring is not broken so hopefully it will be alright. I'll take some emery cloth and smooth out the scratches before installing the new seals. I have five new seals on the way from the dealer, $3.00 each for the seals plus shipping, should have them on Tuesday morning. The new replacement valve would be just under $500.00.
I will let you all know how it turns out once I get the valve reinstalled back in the machine, hopefully on Tuesday.
Nige
Senior Member
Scrapper, those 4 black particles in the photo above. It's difficult to tell from a photo but are they metallic or non-metallic..? If they are non-metallic then how hard are they..? In other words can you crush them with a pair of pliers..? If you can they are likely what's left of the missing seals.
Another comment regarding O-Rings that you posted earlier. Those O-Rings that have a backup ring (the white Teflon Ring) should really not be installed without that ring otherwise the O-Ring will tend to deform under pressure and start to leak before very long. A black rubber washer will not work reliably for long - the hydraulic shop should have told you this.
O-Rings in this type of application need to be 90 Duro-rated nitrile rubber (not 75 Duro silicone rubber under any circumstances), that's the only material that will stand up to hot hydraulic oil for any length of time. If your local hydraulic shop cannot supply nitrile O-Rings or give you a blank look when you ask for them, head straight for your nearest Cat dealer. I'm not 100% familiar with your 345 but I know some exacavators use metric-size seals in the hydraulic systems. The difference between inch sizes & metric might only be a few thousandths in some cases but it'll be the straw that breaks the camels back.
Another comment regarding O-Rings that you posted earlier. Those O-Rings that have a backup ring (the white Teflon Ring) should really not be installed without that ring otherwise the O-Ring will tend to deform under pressure and start to leak before very long. A black rubber washer will not work reliably for long - the hydraulic shop should have told you this.
O-Rings in this type of application need to be 90 Duro-rated nitrile rubber (not 75 Duro silicone rubber under any circumstances), that's the only material that will stand up to hot hydraulic oil for any length of time. If your local hydraulic shop cannot supply nitrile O-Rings or give you a blank look when you ask for them, head straight for your nearest Cat dealer. I'm not 100% familiar with your 345 but I know some exacavators use metric-size seals in the hydraulic systems. The difference between inch sizes & metric might only be a few thousandths in some cases but it'll be the straw that breaks the camels back.
Last edited:
>HevyIndsMFGng<
Well-Known Member
Great thread! Enjoyed following this one, hope everything works out and sorry to hear about the crappy company you had to deal with while buying this machine!
Received the 5 new seals on Tuesday. Total invoice including shipping costs $22.40.
I filed the scratches on the valve, greased up the seals and managed to slide them on valve into the correct grooves, took out the plug on the cap so I could slide the valve down into the cap (if I didn't air pressure built up wouldn't allow me to slide the valve all the way into the cap) and then greased up the whole regen valve and stuffed it back up into the main valve and tightened the four bolts. A piece of 1" pipe about two foot long worked good for pushing the regen valve back up into the main valve. It's a tight squeeze up in there. The whole job didn't turn out to be half as bad as I thought it was going to be when I first looked up at the under side of the main valve.
I started up the machine and moved the jaw on the shear back and forth a little bit and then checked for leaks around the reinstalled valves, which there were none. I then grabbed a cold beer out of the refrigerator and turned up the RPM's on the old CAT and proceeded to try out the shear.
Holy Crap, this thing will cut though anything now. I can cut though stuff I couldn't cut before even when the machine was cold. When the guy I talked to at Genesis said "that shear should go through two or three I-beams at a time without any problem" he wasn't kidding. So I'm thinking OK the hydraulic oil will warm up and the shear will start losing pressure soon. Well it was over 90 degrees outside and it actually took longer for the oil temperature to come up than it did before when the outside air temp was much cooler. I would imagine this was because the hydraulic oil bypassing the regen valve before generated a lot of heat which is not the case now. The oil temperature got up to three bars on the gauge and the shear was cutting good, four bars and still slicing throw anything I could fit in the jaws.
Hats off to Per Eriksson for diagnosed this problem to the T.
I just wish Sargent's Equipment would have spent more time testing this machine before they sold it and not lied to me when they said they ran the machine up to temperature and tested everything and the shear works just fine. A few seals and an hours worth of labor wasn't worth losing a potential repeat customer. I will never buy another piece of equipment from Sargent's Equipment after what I experience with this one. I'm just glad I didn't send the shear cylinder to them to have it rebuilt. I would have had $2500.00 plus shipping costs invested in that and it wouldn't have fixed the problem. Which I'm almost sure they wouldn't have reimbursed me for when it turned out to be 5 O-rings that cost $15.00.
Thanks for everyone's help. I'm glad you enjoyed the thread. I'm hoping to make a video of the shear in action and when I do I will post it here for everyone to enjoy.
I filed the scratches on the valve, greased up the seals and managed to slide them on valve into the correct grooves, took out the plug on the cap so I could slide the valve down into the cap (if I didn't air pressure built up wouldn't allow me to slide the valve all the way into the cap) and then greased up the whole regen valve and stuffed it back up into the main valve and tightened the four bolts. A piece of 1" pipe about two foot long worked good for pushing the regen valve back up into the main valve. It's a tight squeeze up in there. The whole job didn't turn out to be half as bad as I thought it was going to be when I first looked up at the under side of the main valve.
I started up the machine and moved the jaw on the shear back and forth a little bit and then checked for leaks around the reinstalled valves, which there were none. I then grabbed a cold beer out of the refrigerator and turned up the RPM's on the old CAT and proceeded to try out the shear.
Holy Crap, this thing will cut though anything now. I can cut though stuff I couldn't cut before even when the machine was cold. When the guy I talked to at Genesis said "that shear should go through two or three I-beams at a time without any problem" he wasn't kidding. So I'm thinking OK the hydraulic oil will warm up and the shear will start losing pressure soon. Well it was over 90 degrees outside and it actually took longer for the oil temperature to come up than it did before when the outside air temp was much cooler. I would imagine this was because the hydraulic oil bypassing the regen valve before generated a lot of heat which is not the case now. The oil temperature got up to three bars on the gauge and the shear was cutting good, four bars and still slicing throw anything I could fit in the jaws.
Hats off to Per Eriksson for diagnosed this problem to the T.
I just wish Sargent's Equipment would have spent more time testing this machine before they sold it and not lied to me when they said they ran the machine up to temperature and tested everything and the shear works just fine. A few seals and an hours worth of labor wasn't worth losing a potential repeat customer. I will never buy another piece of equipment from Sargent's Equipment after what I experience with this one. I'm just glad I didn't send the shear cylinder to them to have it rebuilt. I would have had $2500.00 plus shipping costs invested in that and it wouldn't have fixed the problem. Which I'm almost sure they wouldn't have reimbursed me for when it turned out to be 5 O-rings that cost $15.00.
Thanks for everyone's help. I'm glad you enjoyed the thread. I'm hoping to make a video of the shear in action and when I do I will post it here for everyone to enjoy.
Last edited:
Per Eriksson
Senior Member
Excellent.