Cheap Northern tool cylinders=junk

[muddstopper]

Well, today I decided to do a little maintenance to my splitter. The big thing I really wanted to take care of was opening up the ports to the cylinder. I had bought a 5in bore cyl from Northerntool a couple of years ago that was supposed to have 3/4" ports. Well the ports are 3/4, but when you look down in the bottom of the port, there is about a 3/8 hole for the oil to go thru. When I bought the cyl, I didnt have time to take care of that problem, so today was the day. I had to fab up a spanner tool to remove the cap so I could pull the rod and piston. I wanted to be able to clean out any shavings that would get in the cylinder when I drilled out the ports. I have to say I was really disappointed in what I found. The inside of the cylinder was full of metal shavings. The piston looked like it had been run thru a grinder and the cyl bore was all scarred up. Now when I bought this cylinder, It was a replacement for the 4in bore cyl I had robbed off my dump trailer when I built the splitter and that cylinder is still working just fine back on my dump trailer. I know my oil is clean and I have a suction screen in the bottom of my tank as well as a 10micron filter on the return. There is only one place this metal could have come from and that is from inside the cylinder when it left the factory. This wasnt little specks of metal, it looked like milling or drill chips, was even some spirals of metal. Wasnt just a little bit either, I could scrap them up with my hand. Had I not of taken the cyl apart, I wouldnt of found this mess until something failed. As it is, I had to put it back together with all those messed up parts. It still works and doesnt seem to be bypassing oil internally, I used it to split some 40in dia whiteoak after i put everything back together, but how long will it last, who knows. All I can say is if you buy a chinese made cylinder from Northern Tool, you need to take it apart and clean it out before you put it on your machine.

Just to add, I opened the ports to 5/8 dia and I could tell a definate difference in speed, altho I didnt time cycle times.

 

[Fawken]

Do you know who actually makes the cylinder? I get my cylinders from Surplus Center and have found they're a lot cheaper than Northern tool or TSC. Surprised you got any service at all out of it.

 

[BukitCase]

If you opened the ports from 3/8 dia. to 5/8 dia, you would have increased flow by 2.78 TIMES, assuming pressure remained the same. No wonder you thought it was faster... Steve

 

[muddstopper]

I dont know who made the cyl. Pretty sure its chinese. I bought it on sale for less than $300. I knew opening the ports would let more oil flow. I couldnt tell any difference in pressure, but I havent found anything that would stop it yet. I have a 28gpm 2stage pump, what I was really hoping was that removing the restriction might improve some of my over heating problems. It didnt, well maybe a little, but not enough to suit me. My next option is going to be increaseing tank capacity. I know my tank is a little small. I went from a 4in cyl to a 5 in and from a 14gpm single stage pump to a 28gpm 2 stage. My control valve is rated for 25gpm. I need to add a dump valve to the return. One day I will finish building this machine, LOL

 

[porky69]

Recommended IDEAL reservoir size is 3 to 5 times the gpm rating of your pump plus air space of 10%. ie (28gpm*3)*1.1=92.4gallon total capacity.

More realistic is probably 1.5 to 2time. (28gpm*1.5)*1.1=46.2gallon.

 

[CurlyDave]

The reservoir cools by convection to the surrounding air, which increases with reservoir surface area. If everything else is working with the current reservoir, I would be inclined to try soldering some fins on the outside which would increase cooling without disturbing anything else.

 

[muddstopper]

Dave, when I built the splitter, it had a much smaller pump on it than it does now. The cyl was also smaller, 4in versus the 5in one it has now. The hyd tank only holds about 7 gals. I usually just run the machine for a little bit at a time, but every now and then I get some help and I will split until it starts getting really hot and take a brake to let it cool down. When I added the larger pump and cyl, I knew a tank upgrade would be in the future and I have also secured a oil cooler I might add. My wood for this season is already in the shed, so I will probably spend a little time upgrading to a bigger tank. I will probably save the oil cooler for the processor I am building.