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Right side track slower then left?

redline808

Well-Known Member
Joined
Jul 4, 2007
Messages
101
Location
Hawaii
Alright, I drove my machine today. New problem??

The new drive motor, on the right track is a lot slower then the left track? do drive motors have left and right? there was 4 ports on the drive motor for hydraulic lines. 3 were used one is plugged. When I installed the unit, the top one was plugged and the next 3 were open. I needed to put my small line in the top port, so I took that plug out and moved it to the bottom port. The bottom port was plugged on the original motor. Could I have that wrong? My machine is low on hydraulic fluid to, could that be a problem? I would think both tracks would be slow if it was fluid level related.

Any ideas please
 

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stumper120

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Joined
Jun 11, 2007
Messages
123
Location
newhampshire
congrats looks like you are finaly getting somwhere. first off fill up your hydro fluid you have a lot of time into this thing only to burn up a pump. unless you need another vacation lol. just cause the drive bolts in doesent mean the gear ratio is the same if you have a two speed motor just run the speed that closer matches the other motor. the ratio is not only changed buy the overall planetary system but the angle of the swash plates in the motor itself. you may be able to find different swash plates to meet your needs
 

redline808

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Joined
Jul 4, 2007
Messages
101
Location
Hawaii
Thank you, I am not a mechanic but I seem to be learning, the hard way...lol. My original drive motor does not have 2 speeds. the machine is a Kobelco.

Ok, bare with me, here comes the questions:
How can I tell if this new drive motor is a 2 speed?
If it is a 2 speed motor, how do I run the speed that closely matches?
What are swash plates?

I do have my old drive motor for parts.

If the new drive motor is a 2 speed unit, how could I run both speeds? I ask, because I actually bought both sides, but only changed 1, because I could only carry back 1 and also because the other side on the machine was still good. but if it is a 2 speed motor, if it is worth it, I could make a 2 speed machine. then I could drive faster?

Thanks for the help.
 

stumper120

Well-Known Member
Joined
Jun 11, 2007
Messages
123
Location
newhampshire
for sake of simplicitcy i whould install the matching drive. you sed you plugged on port on the newer motor. if it has 4 ports total it changes speeds with a different supply line change in the house or upper unit. requiring an extra line in the swivel joint. drive units have axial piston motors on them. google it up cause its complex to explain but with you obvious skill you will figure it out buy looking at some pics. you can plug the high speed port and run them in low. high speed has very little tractive force for turning and hill climbing anyway. plus it will finish off whats left of your undercarrige in a hurry. whats the rush round here were paid buy the day/hour.:usa
 

redline808

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Joined
Jul 4, 2007
Messages
101
Location
Hawaii
I tried to google something on what you said, but came up empty. do you have a phrase I can google or link for some pictures to look at.

I am more then happy with one speed. but right now it is retardedly slower then the other side? I would put in the other drive unit, though I left it at a friends house in Thailand, so for the moment, I cannot go get it...., even though I would like to for fun.

My old drive motor had 4 ports too, and one was plugged. does the top and bottom ports control the drive speed?

Thanks.
 

Ohio Takeuchi

Active Member
Joined
May 30, 2007
Messages
43
Location
Columbus Ohio
Thank you, I am not a mechanic but I seem to be learning, the hard way...lol. My original drive motor does not have 2 speeds. the machine is a Kobelco.

Ok, bare with me, here comes the questions:
How can I tell if this new drive motor is a 2 speed?
If it is a 2 speed motor, how do I run the speed that closely matches?
What are swash plates?

I do have my old drive motor for parts.

If the new drive motor is a 2 speed unit, how could I run both speeds? I ask, because I actually bought both sides, but only changed 1, because I could only carry back 1 and also because the other side on the machine was still good. but if it is a 2 speed motor, if it is worth it, I could make a 2 speed machine. then I could drive faster?

Thanks for the help.

1. Redline, If you motor has 4 ports it is a two speed motor. Basically, your ports will be forward, reverse, case drain and two speed.

2.If you have to choose low or high speed. You have to choose low speed. Your machine will not turn correctly or perhaps not at all. Plus you will not be able to pull steep grades. Even if that means you motors run at different speeds.

3. Simply, swatch plates are part of your drive motor the hydraulic fluid goes through and makes your drive motor work. They are part of the "motor" not the gears.

It would not be easy to add two speed to a machine that is not equipped from the factory. I would suggest using both motors and do not mess with the two speed. Also be careful, on some motors the two speed and the drain our the same size lines. Do not hook the drain where the two speed goes. You will not have a drive motor for long. Hope this helps
 

redline808

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Joined
Jul 4, 2007
Messages
101
Location
Hawaii
1. Redline, If you motor has 4 ports it is a two speed motor. Basically, your ports will be forward, reverse, case drain and two speed.

2.If you have to choose low or high speed. You have to choose low speed. Your machine will not turn correctly or perhaps not at all. Plus you will not be able to pull steep grades. Even if that means you motors run at different speeds.

3. Simply, swatch plates are part of your drive motor the hydraulic fluid goes through and makes your drive motor work. They are part of the "motor" not the gears.

It would not be easy to add two speed to a machine that is not equipped from the factory. I would suggest using both motors and do not mess with the two speed. Also be careful, on some motors the two speed and the drain our the same size lines. Do not hook the drain where the two speed goes. You will not have a drive motor for long. Hope this helps

Do you know anything about the "HY-DASH" drive motors. specificly which port is what? looking at the photo above.

The swatch plates, you say is part of the motor, is the motor the part that the hydralic lines are connected to which has 6 hex bolts holding it on? if so, can i take my old one, off my old drive motor and put it on the new drive motor? would that solve my problems?

Thanks.
 

Ohio Takeuchi

Active Member
Joined
May 30, 2007
Messages
43
Location
Columbus Ohio
Do you know anything about the "HY-DASH" drive motors. specificly which port is what? looking at the photo above.

The swatch plates, you say is part of the motor, is the motor the part that the hydralic lines are connected to which has 6 hex bolts holding it on? if so, can i take my old one, off my old drive motor and put it on the new drive motor? would that solve my problems?

Thanks.

I am not familiar with the specific motor. I was trying to make it simple when I said the swatch plate was part of the motor. You can not switch anything around. They are very specific for each motor. The swatch plate is just a part in the motor. Like a piston would be part of an engine.
 

drag1line

Well-Known Member
Joined
Nov 2, 2007
Messages
127
Location
Houston, Texas
The Kobelco 03 was called the SK903 or SK 60 in the US. Talked to a Buddy who has worked with Kobelco for a long time.
Call your dealer for a Service Bulletin number HE-195-A. While not specifically for this unit, it does address the Hy-Dash motors with warnings about connections.
Good Luck
PS If you are walking and boom up,,does the machine straighten out? With the tracks in the air on each side, do the tracks run the same RPM on each side? No, you may have a pump problem or a problem with the new motor. Piston Motors can be checked via case drain flow amount at FULL STALL pressure. They should have very low flow...Around 1-2 GPM at this size, but very similar on each side.
 

redline808

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Joined
Jul 4, 2007
Messages
101
Location
Hawaii
Alright, got some insight today from an expert in drive motors. The drive motor I purchased does not have the same gear ratio as I hoped. Oh well, at least I got both sides, now I just have to change the other.

Now some tech. My old motor and the new one both have 4 ports. this is a single speed motor. 2 speed Hy-dash motors have 5 ports. The 4 ports go as follows. top and bottom are drains, one is plugged, doesnt matter which. center are A and B which are forward and reverse. My old motor had a ratio of 64:1 the new motor is a whopping 108:1, yes, it will be very slow, which I am not to pleased about, but I am trying to look at the bright side, now I should be unstoppable with all that torque. Buwahahahah.

Thanks everyone!
 

Countryboy

Senior Member
Joined
Jun 8, 2006
Messages
3,276
Location
Georgia
Occupation
Load Out Tech. / Heavy Equipment Operator / Locomo
now I should be unstoppable with all that torque. Buwahahahah.

Glad to hear you got it worked out. :)

Just weld a ripper on the back, add a blade in the front and you'll have a dozer-vator. :D
 

philsbs

Member
Joined
Nov 21, 2007
Messages
9
Location
Northern WI
Did you take the old drive apart? I have a Komatsu pc50uu-2 that has the same type of drive (hydash) and it leaks gear oil when its full. The drive sounds ok and no metal in the gearbox so I would like to repair it before it does some damage. I can't find a manual or any info on how to take it apart. Any info would be greatly appreciated.
Thanks
 

redline808

Well-Known Member
Joined
Jul 4, 2007
Messages
101
Location
Hawaii
if you need to remove the front cover, this is what i did.

on the front where you fill and drain the gear oil. around that edge is a wire clip. pull the wire clip out. i used a scratch all and cleaned out the groove then used the point to pry out the leading edge. once it was out, i grabbed it with a vise grip and used a flat head to help it along. came out pretty easy. next you soak that groove with penetrating oil, more if you haven't already. remove the drain and fill plugs, thread a bolt into them and tighten it in, when the bolt bottoms out it keep turning it, slowly, it will act as a reverse press lifting the cover off. you may need to use a hammer and heat around the edge to help it. simple as that. lol. once you get it off, there should be a large o-ring seal. anyone else please comment if this way is not the best way. good luck.
 

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philsbs

Member
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Nov 21, 2007
Messages
9
Location
Northern WI
Thanks for the great illustration. I'm not sure if I have to take the cover off or not. It seems to be leaking on the inside between the motor and the final drive. I just don't know how to get at that seal.
 

redline808

Well-Known Member
Joined
Jul 4, 2007
Messages
101
Location
Hawaii
Thanks for the great illustration. I'm not sure if I have to take the cover off or not. It seems to be leaking on the inside between the motor and the final drive. I just don't know how to get at that seal.

oh, that one is easy. if your talking about separating the head from the rest of the unit. just remove the hydraulic lines, take out the allen head bolts, i think there is 6 of them and it comes right off. you should take the drive motor out and lay it on its face to do this. there is a bunch of springs in there that might be a pain to re-install if on the machine.
 

joshy7

New Member
Joined
Dec 15, 2010
Messages
1
Location
australia
5 port hydash motors

I know this is an old thread but does anyone have the hydraulic schematics for the 2 speed hydash motors Mine has 5 ports but 2 are linked converting it to a 1 speed motor.
 
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