Splitter Problem-Filter Blew(Pic)

[timbrjackrussel]

Hydraulic filters that do more harm than good - Part 2
In response to my previous article on hydraulic filters and the negative effects of suction strainers, one of our readers wrote the following:


"The one thing a suction strainer does that's worthwhile is to keep out the trash that gets dropped into the tank during service. We lost pumps to things like bolts that we know were not in the tank when it got built. The process of adding hydraulic fluid to the tank often doubles as the trash-installation function. The screens that are often installed in the fill neck usually get a hole poked through them so that oil will go in faster..."

A couple of years ago, I was involved in a case where the seals failed in the swivel on a hydraulic excavator. This allowed the automatic greasing system to pump grease into the hydraulic reservoir.

The grease clogged the suction strainers, which subsequently failed. The wire mesh from the suction strainers destroyed all four hydraulic pumps and several other components.

Had suction strainers not been fitted, it is likely that the grease would have eventually dissolved in the hydraulic fluid with minimal damage to any components.

My point is, I don't use this example as an argument against fitting suction strainers - because grease should not be in the reservoir.

Likewise, I do not consider trash exclusion to be a valid argument for fitting suction strainers - because nuts, bolts or similar debris should not be in the reservoir.

The sloppy operators that allow trash to drop into the reservoir are the same operators that never drain and clean the reservoir, and change the suction strainer. So the suction strainer clogs eventually and the pump fails through cavitation. Therefore, with or without the suction strainer, the pump is destined to fail prematurely.

The correct solution is not to allow trash to get into the reservoir. And this is fundamental to my recommendation to remove and discard suction strainers, where fitted.

Excessive vacuum at the pump inlet caused by suction strainers is a bigger threat to pump life in the long run, than trash that shouldn't be in the reservoir in the first place.

Suction strainers have a by-pass on them so cavitation doesn't happen. If the strainer is vertically mounted the crap will plug only part of the screen and will be cleaned off of the screen at MAINTENANCE time.

 

[cabinman]

Michiagander

Hydraulic filters that do more harm than good - Part 2
In response to my previous article on hydraulic filters and the negative effects of suction strainers, one of our readers wrote the following:


"The one thing a suction strainer does that's worthwhile is to keep out the trash that gets dropped into the tank during service. We lost pumps to things like bolts that we know were not in the tank when it got built. The process of adding hydraulic fluid to the tank often doubles as the trash-installation function. The screens that are often installed in the fill neck usually get a hole poked through them so that oil will go in faster..."

A couple of years ago, I was involved in a case where the seals failed in the swivel on a hydraulic excavator. This allowed the automatic greasing system to pump grease into the hydraulic reservoir.

The grease clogged the suction strainers, which subsequently failed. The wire mesh from the suction strainers destroyed all four hydraulic pumps and several other components.

Had suction strainers not been fitted, it is likely that the grease would have eventually dissolved in the hydraulic fluid with minimal damage to any components.

My point is, I don't use this example as an argument against fitting suction strainers - because grease should not be in the reservoir.

Likewise, I do not consider trash exclusion to be a valid argument for fitting suction strainers - because nuts, bolts or similar debris should not be in the reservoir.

The sloppy operators that allow trash to drop into the reservoir are the same -*perators that never drain and clean the reservoir, and change the suction strainer. So the suction strainer clogs eventually and the pump fails through cavitation. Therefore, with or without the suction strainer, the pump is destined to fail prematurely.

The correct solution is not to allow trash to get into the reservoir. And this is fundamental to my recommendation to remove and discard suction strainers, where fitted.

Excessive vacuum at the pump inlet caused by suction strainers is a bigger threat to pump life in the long run, than trash that shouldn't be in the reservoir in the first place.

Check the source of that article,..If you (tried) to do that It wood be diffiacult,. To get a hydraulic seal to leak and grease to get in that leak, aint going to happen, If it was on the return side, Its possable, But not likley,the turn table bearing will let off most of the grease pressure .Either way, their was more than one problem there,... A hydraulic leak, that was not detected, An opperator that was not paying attention to the gages on the dash, (Hydraulic Filter gauges specifically), I wouldnt go out and strip my equipment of its hyd filters because of one (poor) operators tale, or a (freek) greese suckin insident,. E,J,

 

[Kydan]

While where on Filters

So like is there a big difference between a 10 and 25 micron filter on the Return Side, I had replaced a bad pump and changed the hydraulic fluid. When I went to change the filter that was a 10 micron the guy I got
the pump from a hydraulic specialist said that a 25 will do just fine.What do you all think?..

 

[user 19670]

Car engines do not have as much psi as hydraulic systems, Also when running hydraulic systems oil temp can be 100 degrees hotter than air temp.

"Car engines do not have as much psi as hydraulic systems" - Difference noted but what is the point? The filter is in a pressure line not a suction line.

"Also when running hydraulic systems oil temp can be 100 degrees hotter than air temp" - NO difference noted. Car engines are controlled for temps of 195C and that isn't cool by anyone's estimation.

The comparison was valid. Hydraulics systems in heavy industry typically have a suction strainer and a pressure filter system built in by experts in hydraulics system design.
The course I took stressed this fact for good reason.
In the last 4 years of my career I worked as a Maintenance Planner and I never saw a hydraulics system without a suction strainer in place and a filter [or filter(s)] in the return line to the tank. I had to arrange for maintenance on the hydraulics in my area at work and purchase the replacement parts (in this case the filters).

I've exhausted myself on this subject. Do what you will and have fun no matter what you do.

 

[timbrjackrussel]

A few BIG IFS and A few BIG NEVERS

A little filter info-
If the oil tank is clean and the return line 10 micron filter is piped into the tank - then all oil is filtered that goes back to the tank. Inlet filter is not required since the hydraulic oil will not contain particles large enough to be captured by the coarser mesh strainer.

IF nothing NEVER gets into the tank other than clean oil, and IF nothing NEVER flakes off of the inside of the tank , you MIGHT be OK. If not it could cost a PUMP verse a STRAINER. DO the math $$$$$.

 

[mga]

Ding..Ding.. We have a winner! I just have a strainer in the tank on mine, But if I was to put a filter on it, the suction line to the pump is the place. Good luck where ever you put it..Nothing worse than a oil bath!

the filter mount has a by-pass valve in it. this is so that if the filter ever gets clogged to the point where oil could not pass thru it, the by-pass valve would open and do it's job. if it didn't, pressure would build up and blow the filter. the return flow is considered as a low pressure line.

on the suction line, the physics are different. the suction would open the relief valve and the oil would be sucked past the filter, rendering it useless.

even the strainer could cause problems, so, if using one on the suction line, it has to be checked periodically. if the oil flow is being restricted, it will cause cavitation...which will eventually ruin the pump.

only under special conditions are suction line filters used. you can read more here:

http://www.insidersecretstohydraulics.com/vane-pump.html

that is an excellent web site for hydraulic information

 

[michigander]

Pic of larger return hose

Here is a pic of my larger return hose from filter to tank. Hopefully it will do the job.
Thanks to all the people who voiced their idea's and to debate the pro's and con's of the use of the suction strainer or the return line filter. I know that I learned a lot and thats what this site is for. to all of you.

 

[Blazin]

Hope that does the trick for ya! After all the Spankins that have been handed out...I'll just keep my strainer in the tank (New oil every year/clean/check strainer) with no filter.

 

[timbrjackrussel]

Galvanized fittings are a no no

Here is a pic of my larger return hose from filter to tank. Hopefully it will do the job.
Thanks to all the people who voiced their idea's and to debate the pro's and con's of the use of the suction strainer or the return line filter. I know that I learned a lot and thats what this site is for. to all of you.

I think that I saw galvanized fittings on your pump suction line and on your filter base output.They shouldn't be used as the galvanizing can flake off. I know it may be another "maybe" but it could negate all of your work if the fittings are on the pump intake after the intake screen. The intake on my splitter has a 25 GPM 125 square inch #100 stainless steel mesh to a 1" single wire hose down to the pump that is always lower than the fluid level. A smooth gentle bend up into the pump. Minimal restrictions! I have a magnetic plug in the tank as well. Your larger, less back pressure return hose should help out your filter rupture problem. What oil are you using in the splitter?

 

[michigander]

Timbrjackrussel, Thanks for the tip on the galvanized! I am using tractor hydraulic fluid 10w-20. I think it might be a little thick for the colder months, but be better for using it when its warm.
Another question. I've been trying to find some rubber motor mounts that could be used on this 9 HP Robin. It seems to shake a lot when I'm splitting. I've been looking on Ebay to get some idea's , but haven't found much yet. Ever heard of anyone using these mounts to smooth things out?

 

[timbrjackrussel]

Tighten the engine down to the splitter frame and check the engine service info to see if it has a balancing gear system in it.It may have a problem. Did the motor shake on the previous machine? If no, then check your tire air pressure. I run mine at 15lbs. or else it bounces all over the road when being towed. A lower pressure may help absorb some of the shake.

 

[tanker]

makes no diference what position cylinder is in,it will bleed itself. The return line has no pressureon it just return flow to res. If any more pressure than 60 psi would blow return line off of fittings as your hose clamps are only rated at 60 psi

 

[kevin j]

only under special conditions are suction line filters used. you can read more here:
http://www.insidersecretstohydraulic...vane-pump.html
that is an excellent web site for hydraulic information



1. Brendan Casey also has an email hydr newsletter. go to the site above, or to
http://www.hydraulicsupermarket.com/ and at bottom of page to sign up. OK by him for anyone to sign up.
He sells books, does training. He is among many good sources.

2. motor mounts:
Grainger 5XK44 is a common, two piece, center bonded mount, that use a ¾ inch hole in the base, 3/8 bolts for motor mounting. (4) required, about $4 each. These are quite stiff for the weight of a small engine, but are the smallest Grainger had. With steel through bolt and sleeve, and washer on both sides, the engine is positively restrained in case of rubber deterioration. Simple to use: Just drill out the original motor mount holes in the splitter to 3/4 inch, deburr and install. Raises the engine slightly. My 18 hp engine is more in the weight rating and the mounts are quite effective. I used the mounts between engine and power unit frame, and also between power unit and trailer frame. Makes a sweet and quiet running package.


3. Eric: turning the cylinder so the ports were up allowed the air to go out and back to tank. With ports on side, there is an air pocket up above the port even when piston is full stroked. I am still cautious there is more to the story, but hopefully the larger hose solved it.


kcj

 

[michigander]

Timbrjackrussel, I just bought the motor used. I'm just looking to isolate motor from rest of splitter when its running. It goes down the road nice. There is a torsion flex axle under it.


Kevin J.
1. Yes, I checked that website out. Lot's of good information there.
2.Thanks for the tip about the mounts at Grainger. There is a store about 10 miles away. It looks like just what I was thinking about.

 

[cabinman]

Bubble

only under special conditions are suction line filters used. you can read more here:
http://www.insidersecretstohydraulic...vane-pump.html
that is an excellent web site for hydraulic information



1. Brendan Casey also has an email hydr newsletter. go to the site above, or to
http://www.hydraulicsupermarket.com/ and at bottom of page to sign up. OK by him for anyone to sign up.
He sells books, does training. He is among many good sources.

2. motor mounts:
Grainger 5XK44 is a common, two piece, center bonded mount, that use a ¾ inch hole in the base, 3/8 bolts for motor mounting. (4) required, about $4 each. These are quite stiff for the weight of a small engine, but are the smallest Grainger had. With steel through bolt and sleeve, and washer on both sides, the engine is positively restrained in case of rubber deterioration. Simple to use: Just drill out the original motor mount holes in the splitter to 3/4 inch, deburr and install. Raises the engine slightly. My 18 hp engine is more in the weight rating and the mounts are quite effective. I used the mounts between engine and power unit frame, and also between power unit and trailer frame. Makes a sweet and quiet running package.


3. Eric: turning the cylinder so the ports were up allowed the air to go out and back to tank. With ports on side, there is an air pocket up above the port even when piston is full stroked. I am still cautious there is more to the story, but hopefully the larger hose solved it.


kcj

Ok,.. I dont see how there could be any air left in that space with the cylinder fully stroked, repeitataly, Ive never experinced it,.In my 40 years of experince,. Maybe better said,.. If there was a bubble in the system it went undetected, and caused no problems, I dont think a few bubbles wood cause a filter to puke its guts, (If) it was installed right,= proper micron, proper fittings, proper hose size, and proper tank venting, And, Just because I Question your explanations, at times, You are much more intelegent and experinced then me in hydraulics, Its still hard to figure out why cylinder position has anything to do with an air bubble,.most of my experince with air in the system, has been with farm equipment,.. folding tillage tools especially, Thanks, Kevin, Iam looking forward to your log splitter site,..Eric

 

[turnkey4099]

Ok,.. I dont see how there could be any air left in that space with the cylinder fully stroked, repeitataly, Ive never experinced it,.In my 40 years of experince,. Maybe better said,.. If there was a bubble in the system it went undetected, and caused no problems, I dont think a few bubbles wood cause a filter to puke its guts, (If) it was installed right,= proper micron, proper fittings, proper hose size, and proper tank venting, And, Just because I Question your explanations, at times, You are much more intelegent and experinced then me in hydraulics, Its still hard to figure out why cylinder position has anything to do with an air bubble,.most of my experince with air in the system, has been with farm equipment,.. folding tillage tools especially, Thanks, Kevin, Iam looking forward to your log splitter site,..Eric

I agree that a bubble should not cause any problems. All it does is absorb (i.e. compress) to the system pressure. Pressure releases, the bubble expands. It does not cause an increase in pressure. It does cause spongy operation of any hydraulic system though.

As for the bubble position. A bubble will find the highest point in the system and, once there, will remain unless there is an outlet for it. With the fitting on the side, it can't get down to them to be pushed out.

Harry K

 

[triptester]

Air in a hydraulic system acts like a spring .When you apply force to something that is non compressible then suddenly release that force nothing happens. If you apply force to a spring causing it to compress then suddenly release that force there will be a violent reaction.

The filter that may have been designed for 20 gpm in a normal hydraulic system could when the fluid is backed by compressed air be subjected to 80 gpm for a split second causing it to rupture.

 

[mga]

a pressure gauge on the filter will show a steady flow when the control lever is in neutral. the oil is just flowing freely and might be around 10 to 20 psi.

when activating the cylinder the gauge will drop to "0", then all of a sudden jump back to operating pressure when the control lever is switched again. the gauge on mine actually showed a negative number for a brief second or two when there was a sudden stop of the cylinder. regardless, the flow into the filter is never the same constantly. the filter should handle the sudden drops or increase of pressures, especially with the by-pass valve inside of it.

i'm banking on just a defective filter housing.

however, what brand of filter valve housing are you using? model number?

 

[michigander]

I did not see a name on the housing. I bought the filter housing and some other odd parts at Tractor Supply. The filter on it originally was a Cross 25 micron. They sell Cross splitter valves their too, so possibly the housing was made by Cross. Just a guess, I will look closer when I get to splitter tomorrow. I will be installing the rubber mounts on motor tomorrow and let you know how it helps.
Here is the description of the filter, from the TSC webstite.
Full flow efficiency up to the cracking pressure of the integral 15 PSI bypass. 25 micron filter element - general hydraulic system replacement element - for logsplitters, small tractors, etc. Rated to 200 PSI, 20 GPM.

 

[cabinman]

bubble

Air in a hydraulic system acts like a spring .When you apply force to something that is non compressible then suddenly release that force nothing happens. If you apply force to a spring causing it to compress then suddenly release that force there will be a violent reaction.

The filter that may have been designed for 20 gpm in a normal hydraulic system could when the fluid is backed by compressed air be subjected to 80 gpm for a split second causing it to rupture.

Trip, your explanation of traped air in a cylinder, causing a sudden violent release of fluid, far in excess of rated flow or otherwise is certinaly true, But I dont see how there could more then a (vary) small amount of air traped after he ran the machine splitting the smaller pieces of wood, I guess what I am not understanding is,.. When the piston comes to the end of its stroke it pushes everything out, Right? what difference does it make if the ports are on the side or the top? i dont think there wood be more than an oz or 2 room left, for air, and dont see a couple onces of compressed air causing that filter to blow, as far away as it is,. Thanks for taking the time to post, Eric