853 boom up issues

[chesapeake]

had a crack in my aux. pump. removed the pump cleaned everything up and welded the crack in the housing. put everything back together and fired it up. good news is the weld worked great and the leak is stoped. bad news is once i got it back i took it over to a pile of stone and after moving 3 bucket fulls the boom stoped lifting full buckets. i took the bucket off and hook up my breaker and it will not fire at all. (no lift and no aux.) i think its a pressure relief proble,m and not a pump because it just failed and did not "taper off" like the pump was losing power let me know what you think thanks chris

 

[Bobcatdan]

This is a guess. i don't know about 853, but 863 and 873 had a spacer that went on the end of the gear pump shaft to hold the coupler in place. If the spacer is gone, the coupler has enough room to to back off the shaft. Learned this the hard way on an 863. Relief should not just go, if anything I think its failure would lead to high pressure, giving the thing great power until the pump gernatted.

 

[Fishfiles]

I think you need a new pump , welding on it did it in , do a flow -pressure test to verify

 

[chesapeake]

I think you need a new pump , welding on it did it in , do a flow -pressure test to verify

hooked up a pressure gauge and found that the aux peaked out a 1000 psi then droped to 800. i replaced the main relief valve and got the same numbers. tried to adjust the screw and could not get any more psi. took the pump apart when it was welded so all was exposed to the heat was the housing. going to take the pump out tomarrow to check to see and make sure all the interinals are ok. when i put it back together everything seemed to fit very tight (no warping) thanks for the responce talk to you guys later any other ideads let me know chris

 

[Kermode]

hooked up a pressure gauge and found that the aux peaked out a 1000 psi then droped to 800. i replaced the main relief valve and got the same numbers. tried to adjust the screw and could not get any more psi. took the pump apart when it was welded so all was exposed to the heat was the housing. going to take the pump out tomarrow to check to see and make sure all the interinals are ok. when i put it back together everything seemed to fit very tight (no warping) thanks for the responce talk to you guys later any other ideads let me know chris

If you managed to weld the case on a hyd pump and get it to work again without major machining then you are the best welder and hydraulic mechanic guy in the world. Your pump is shot. Your pressure test shows it clearly.

 

[chesapeake]

If you managed to weld the case on a hyd pump and get it to work again without major machining then you are the best welder and hydraulic mechanic guy in the world. Your pump is shot. Your pressure test shows it clearly.

it was a bad gasket on the sprocket bushing! all the fluid was passing by the bushing not allowing it to build pressure replaced it today and its working great. spent more time trying to dial in the the new main relief vavle i installed. Ps not the best welder or machineist in the world just a kid that taught his self to weld and would rather spend a hr or two trying to fix it before i drop a g on a new pump. thanks for the compliment thought. all my buddies said i was wasting my time to. ill post picks of the welded pump lol

 

[Fishfiles]

it was a bad gasket on the sprocket bushing! all the fluid was passing by the bushing not allowing it to build pressure replaced it today and its working great. spent more time trying to dial in the the new main relief vavle i installed. Ps not the best welder or machineist in the world just a kid that taught his self to weld and would rather spend a hr or two trying to fix it before i drop a g on a new pump. thanks for the compliment thought. all my buddies said i was wasting my time to. ill post picks of the welded pump lol

Time will tell if you wasted time or not ----------- I changed a lot of pumps in 753 , 763 and 773 that cracked right thru the threads of the output side , that is the only spot I every seen one crack on one , looking forward to your pic to see where it cracked at , Bobcat came out with a new fitting that had a bevel in the end under the oring , that helped to stop the problem of cracking tjhru the threads ----------- what welding rod did you use

 

[chesapeake]

Time will tell if you wasted time or not ----------- I changed a lot of pumps in 753 , 763 and 773 that cracked right thru the threads of the output side , that is the only spot I every seen one crack on one , looking forward to your pic to see where it cracked at , Bobcat came out with a new fitting that had a bevel in the end under the oring , that helped to stop the problem of cracking tjhru the threads ----------- what welding rod did you use

sorry for the delayed responce my dog chewed through the damn computer charger lol. i used my tig to weld the crack. and yes it was right through the output side of pump. horriable design because of all the virbritation. it really wasnt to bad because the pump was pretty thick. i dug out the crack and then cleaned it really good. onced it was cleaned i went right at. alum. really aint that bad as long as its not to thin. spent alot of time "welding" and distroying (lol) tarp arms for my roll off trucks they are way to expensive to replace when they brake. which happens alot due to the truck bouncing around when there empty. my dad had a little saying that "if one man can do or fix something so can this man". taught my self alot of stuff like this from a little trial and error. actually got pretty good at welding cracked engine blocks and heads too. whats the best way to post pics to these threads havent be able to figure it out chris

 

[Bobcatdan]

sorry for the delayed responce my dog chewed through the damn computer charger lol. i used my tig to weld the crack. and yes it was right through the output side of pump. horriable design because of all the virbritation. it really wasnt to bad because the pump was pretty thick. i dug out the crack and then cleaned it really good. onced it was cleaned i went right at. alum. really aint that bad as long as its not to thin. spent alot of time "welding" and distroying (lol) tarp arms for my roll off trucks they are way to expensive to replace when they brake. which happens alot due to the truck bouncing around when there empty. my dad had a little saying that "if one man can do or fix something so can this man". taught my self alot of stuff like this from a little trial and error. actually got pretty good at welding cracked engine blocks and heads too. whats the best way to post pics to these threads havent be able to figure it out chris

The pumps normally cracks due to relief pressure getting too high. The pump takes too many shocks from pressure it can't handle and crackes it. Different sonario, I had a T190 gear pump take a digger. Put the new pump on checked relief pressure, 5500 psi! Adjusted it down to 3300 and the customer complained it had no hydraulic power.

 

[Tazza]

The pumps normally cracks due to relief pressure getting too high. The pump takes too many shocks from pressure it can't handle and crackes it. Different sonario, I had a T190 gear pump take a digger. Put the new pump on checked relief pressure, 5500 psi! Adjusted it down to 3300 and the customer complained it had no hydraulic power.

For piccies, if you host them on a site like photobucket. When you have the page open with the image up, right click/copy then go to your post, right click/paste. It should appear.

 

[chesapeake]

For piccies, if you host them on a site like photobucket. When you have the page open with the image up, right click/copy then go to your post, right click/paste. It should appear.

do you have to post it to something i tried to cut and paste it from email but it would not paste

 

[skidsteer.ca]

do you have to post it to something i tried to cut and paste it from email but it would not paste

Chesapeak. The photo must be hosted (uploaded to online storage) online at a site like photobucket, not at SSF.
Then open it, copy and past into text box here, be sure to hit enter after each paste as they get too wide to view.
To paste links here make sure you hit the space bar once after you paste the link, at that pointit will turn blue meaning its working.
Ken

 

[HarryN]

Chesapeak. The photo must be hosted (uploaded to online storage) online at a site like photobucket, not at SSF.
Then open it, copy and past into text box here, be sure to hit enter after each paste as they get too wide to view.
To paste links here make sure you hit the space bar once after you paste the link, at that pointit will turn blue meaning its working.
Ken

I believe IE works better when using this site. Other browsers work but are more difficult because of how the site is set up. Hope you figure it out with the suggestions given, as we love pictures. There are a number of posts explaining how to do it if you need more help. Just do a search.....