Hydraulic Motor

Jeff B said:
Have you put a flow meter on your pump to verify that? Your pump is probably a little less and loosing it through the case due to wear. However, if your concerned about to much flow you can put an inline flow divider and dump excess to tank. Also, stay away from White motors, they are junk.
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I have not, I turned my hiflow setting down to 37gpm just to be safe, I don't think I will notice any decrease in performance and it gives me a little peace of mind.
 
YotaOnRocks said:
I have not, I turned my hiflow setting down to 37gpm just to be safe, I don't think I will notice any decrease in performance and it gives me a little peace of mind.
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Is that cutter rated for high flow? I've never actually seen a high flow brush cutter and I've used several including a few from C.A. . I'd run it on low
 
braxton357 said:
Is that cutter rated for high flow? I've never actually seen a high flow brush cutter and I've used several including a few from C.A. . I'd run it on low
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The sticker they put on it says it is and I paid extra for high flow, but after my interactions with them I have little faith in anything they say or do.
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well the picture uploaded a little blurry, but the big white sticker on it says 27-40gpm
 
braxton357 said:
Well there you go then. I'm pretty surprised they are treating you so shitty on service
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I had nothing but great things to say about them until how the issues with this cutter were handled. All my stuff is for personal use, I don't make a dime with them, so a 8k dollar paper weight and no willingness to help me has left me rather sour.

I took it back to them after running it for only 2 hours initially and it started making terrible noises, they had it for a month or so and called and said they replaced the hydraulic motor. I get it back and the pressure relief valve block is no longer on it and the hoses now have a check valve between them. They said the motor was bad and they did away with the valve block because they were causing issues on other cutters.

Fast forward to a couple months past my 1year warranty expired and I fired it back up (my svl95 was down for a while with a dead injector) and after maybe 2 more hours the thing started pouring oil out around a drain plug. I put an oring on the plug and about 2 hours later I noticed the terrible noise it was making.

I called them and asked for help troubleshooting and no return calls, just promises to figure something out and call me back. I continued to call and it was always the same story, "I'll call you back this afternoon with some answers after I talk to our expert", then no return call. This went on for a couple months before I asked them if the replacement motor had a warranty and they told me it was the original motor, all they did was remove the problematic relief valve.

Several times during our conversations he would tell me they never have issues out of these motors, only mine and 2 others around the same time had issues. Seems to me like they had a bad run of motors at the factory but I'm no expert. But they refuse to do anything to help me and what really pissed me off was when I called to see if they would sell me one off their shelf he said they didn't have any, I asked if he could help me find one and he just dismissed me and ended the call.

I know that's long winded but it felt good to vent in text.
 
Well I made a big mistake, evidently I struggle with reading comprehension. My original motor is a knock off of a Char-Lynn 6000 with the exception that dynamic offers a 1.250" 14 tooth splined shaft and Char-Lynn only has a 1.5" 17 tooth splined output shaft. Through all this I was looking at the diagram for my dynamic model number and didn't realize it was 1 letter off and had a custom sized output shaft.

What do y'all think my options are here? I don't really want to have to buy another one from dynamic but it seems pulling the output shaft out of the new motor and having it machined down is about my only option if I keep it. Here is a pic of what it mounts to. I looked up the manufacturer of the bearing housing hoping they offered a shaft for it that would accept the new shaft but they do not.

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The 1.5" 17sp is pretty standard from a few manufacturers, surprised they went smaller. That being said I'm sure it hurts to spend more but looks like you can buy the same motor you took off for under $750, I'd just go back with the same...and maybe replace the hydraulic fluid and filter in your svl at the same time
 
braxton357 said:
The 1.5" 17sp is pretty standard from a few manufacturers, surprised they went smaller. That being said I'm sure it hurts to spend more but looks like you can buy the same motor you took off for under $750, I'd just go back with the same...and maybe replace the hydraulic fluid and filter in your svl at the same time
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I just can't find anyone selling the exact motor I took off, the part number after I look closer is bmk6-200-cc-fc-sf5. I will call them again and see if they can put me in touch with a supplier.
 
do you have a char lynn part number? I can get in touch with our sauer danfoss supplier and see if they have an off the shelf cross over.
 
Jeff B said:
do you have a char lynn part number? I can get in touch with our sauer danfoss supplier and see if they have an off the shelf cross over.
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112-1058-006 is what I had ordered, it is an exact match to what I need except it has a 1.5" 17tooth output, I need a 1.25" 14tooth output. I called dynamic today and they told me it was $1700 and a 48 week lead time.
 
Got any more pictures or a breakdown of hoe they did the blade carrier/spindle? If it can be wire edm'd rather than ram edmd I can get it done for nothing. It's almost like they found some surplus motors or something, dynamic doesn't even list 1.25 14 as an option for bmk 6 series...
 
braxton357 said:
Got any more pictures or a breakdown of hoe they did the blade carrier/spindle? If it can be wire edm'd rather than ram edmd I can get it done for nothing. It's almost like they found some surplus motors or something, dynamic doesn't even list 1.25 14 as an option for bmk 6 series...
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Dynamic has a note at the bottom of the bmk6 catalog page that says custom output shafts available. The spindle is a Omni gear mdh65
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I think they did the 1.25 shafts because they use a bmt motor for the low flow cutters and they have a 1.25 shaft. I'm guessing this allowed them to source a high flow motor without redesigning anything else on the cutter.
 
YotaOnRocks said:
112-1058-006 is what I had ordered, it is an exact match to what I need except it has a 1.5" 17tooth output, I need a 1.25" 14tooth output. I called dynamic today and they told me it was $1700 and a 48 week lead time.
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I'll need the correct part number that has the correct shaft.
 
Now that I reread thread I see the confusion and different part numbers. This is actually an easy fix, buy a new bmk6-200-cc-(fe or g2 or t1 or y1)-sf5 for the best price you can find, pull the front plate off and swap output shafts.

Surplus center "has them on order" for $585.
 

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braxton357 said:
Now that I reread thread I see the confusion and different part numbers. This is actually an easy fix, buy a new bmk6-200-cc-(fe or g2 or t1 or y1)-sf5 for the best price you can find, pull the front plate off and swap output shafts.

Surplus center "has them on order" for $585.
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Dammit man, that's the solution!
 
braxton357 said:
Now that I reread thread I see the confusion and different part numbers. This is actually an easy fix, buy a new bmk6-200-cc-(fe or g2 or t1 or y1)-sf5 for the best price you can find, pull the front plate off and swap output shafts.

Surplus center "has them on order" for $585.
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NO-Homo......

I love you, simplest solution staring me right in the face. Thanks man
 
So I'm back to dealing with an issue with this thing. Put the new motor on a couple years ago and ran it for an hour or so without any issue until it would randomly stop spinning the blades. I'm fairly certain the machine was still sending hydraulic flow to the motor, because every time it happened, I would see the hoses move when I cut off the aux hydraulics.

I have had nothing but trouble out of this thing and got pretty discouraged and threw it under the front of a storage trailer.

Needed it on a job so I grabbed it out of storage, it worked during a short test, so I loaded it up. Within a couple minutes of cutting at the job, it started doing the same crap

I would notice that it didn't seem to be cutting and when I checked the blades weren't turning. I had to complete the job, so I kept playing with it to see if I could figure it out. I found that if I throttle the machine down, waited a minute, and slowly throttled it back up, the blades would spin up and work 8 out of 10 times. A heavier load on the cutter seems to trigger the issue. I'm not trying to cut anything crazy with it.

Im wondering if the check valve , they call it an H valve, is causing issues? What say our resident experts? Below is a before and after photo of what I was cutting and a picture of an "h" valve setup, like I have.
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YotaOnRocks said:
So I'm back to dealing with an issue with this thing. Put the new motor on a couple years ago and ran it for an hour or so without any issue until it would randomly stop spinning the blades. I'm fairly certain the machine was still sending hydraulic flow to the motor, because every time it happened, I would see the hoses move when I cut off the aux hydraulics.

I have had nothing but trouble out of this thing and got pretty discouraged and threw it under the front of a storage trailer.

Needed it on a job so I grabbed it out of storage, it worked during a short test, so I loaded it up. Within a couple minutes of cutting at the job, it started doing the same crap

I would notice that it didn't seem to be cutting and when I checked the blades weren't turning. I had to complete the job, so I kept playing with it to see if I could figure it out. I found that if I throttle the machine down, waited a minute, and slowly throttled it back up, the blades would spin up and work 8 out of 10 times. A heavier load on the cutter seems to trigger the issue. I'm not trying to cut anything crazy with it.

Im wondering if the check valve , they call it an H valve, is causing issues? What say our resident experts? Below is a before and after photo of what I was cutting and a picture of an "h" valve setup, like I have.
View attachment 443526View attachment 443527View attachment 443529
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Sounds like something is going on with that valve and once the pressure gets high enough to open it, it is just bypassing all the flow. Will it allow you to spin the blades in either direction, and is the behavior the same in both directions?
 
I had a hydraulic circuit in a trash compactor give an entire team fits. All three shifts had opinions tried options and all of us were failing.
What we knew was the cylinder catastrophically failed and sent the welded cap to the ceiling. What we knew was after rebuild and installing we had a multitude of symptoms ranging from cavitation, surging, no flow, perfect flow and anything else you could think up. We had dang near replaced disassembled and adjusted everything except the cylinder.
I got slated for tear down. Taking one off the hoses I happened to glance into the fitting. Just inside the crimp was a larger piece of rubber. Curiosity and a crap ton of tugging with the help of a vice yielded a oring sized to fit the ram cylinder. Whole, not cut, not nicked and in a hose that meant it had to have traveld through nearly the entire circuit. It was nearly the diameter of the id of the hose and folded flat.

Put it back together and it was finally fixed.
 
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