List of Upgrades to Vermeer SC252

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I agree about the wasted time!!! Before I bought my Kubota I thought about installing two Kohler engines - don't laugh, I've seen it done on some Dixie Chopper Mowers. Could you imagine 50HP on one of these!

I don't have to imagine. I have 60!! hehehe :greenchainsaw:
 
Apex

Don't worry about your pump, the one on my diesel has over 4,300 hours on it and I have not even replaced a seal.
 
I did the 3" pump sheave changeover and my pump howled like a banshee!!
The first job I took it on , the customers dog hid under the doghouse !!! The pump also seemed to be a lot hotter to the touch than usual. I was afraid of burning the pump up and not finishing the job.
I had taken along the original 5" sheave ,so I stopped and changed back to the original. The next day ,I drained and changed all the hydraulic fluid & filter,removed the suction hose and checked for blockage (found no blockage). I haven't re-installed the 3" ,but I'm real hesitant to do so. Any of you guys that report no pump problem ,does your pump "howl" ??? any signs of cavitation,heat,pump wear ,etc

I did like the increased ground speed ,but the howling hydraulic pump was hard to put up with.
Stan
 
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Yes, my pump is now noisy. It doesn't howl loud enough to scare a dog though. It doesn't bother me, I wear ear plugs. I plan on changing the hydraulic fluid to Amsoil synthetic to decrease cold weather warm up time and cut down on fuel/power consumption. The machine is just unbearable in stock form. With the conversion I can actually get to/from/around the stumps in a timely fashion. I am still going to change the drive gear ratio on the wheel/drive motor combo to increase drive speed to a good pace. Right now the pace is just bearable. The wheel drive motor has so much more power, they will spin on any surface.

I think switching over to synthetic fluid will cut down on pump noise too. Hopefully.
 
You might try changing to a lighter hydraulic oil, or you could increase the diameter of the suction line between the pump and the tank.

The problem with lighter hydraulic oil is once it is hot it will bypass in the motor easier and you will lose power and speed - which is what you are after to begin with.

If you know the pump displacement, you can calculate the speed based on the sheave ratio, then you will know the GPM you are trying to pump. With the GPM you can find recommended suction hose diameter.

http://www.surpluscenter.com/Hydraulic.htm

http://www.hydraulicsupermarket.com/upload/db_documents_doc_12.pdf
 
Maybee they have made some changes in the later models, my units are a 1999 & 2001 and both machines are as quite with the pulley change as they were prior to the change.
 
For those of you that care I did a little research on the pump last night. It is a Sauer Danfoss Part # 29YBAD012-2LB. At 3,000 Rpm it delivers 2.6 GPM, at 3,600 RPM it delivers 3.92 GPM and at 4,000 RPM it delivers 4.8 GPM. 4,000 RPM is the highest recomended RPM. THe input flow calls for 8.2 GPM with and output of 4.8 GPM @ 4,000 RPM. If you want more flow order a 43YBAD012-2LB pump and it will give you a higher flow rate at a lower RPM. All figures are at 2,000 PSI.
 
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I've got an 03, I'll check to see what number I have, but sounds like a new pulley and belt would be cheaper than a new pump.

BTW, thanks for the research!


Stumper63
 
Reviewing the specs on the 43 YB pump it may increase flow to much even with the stock pulley. It puts out 7.5 GPM @ 3,000 RPM and 8.5 GPM @ 3,500 RPM. Requires 11.4 GPM input to deliver 8.5 GPM out put. By the way the last 29YB pump I bought through the aftermarket cost me $210.00 + Frght.
 
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Just for Giggles I checked the pump speed at full throttle on both units today.
Lombardini Diesel 3,750 RPMs
35 HP Briggs 4,350 RPMs
 
Slow turn over on 252

A friend has this SC252 and just called with starting issues. Machine is in a warm garage. When he hits the start key the motor turns over very slow and would catch this summer. He has had the starter cleaned and rebuilt along with the celliniod and put on a new start switch. It still turns slow even with a charger/starter pack on the battery terminals.
Any thoughts? TIA
 
A friend has this SC252 and just called with starting issues. Machine is in a warm garage. When he hits the start key the motor turns over very slow and would catch this summer. He has had the starter cleaned and rebuilt along with the celliniod and put on a new start switch. It still turns slow even with a charger/starter pack on the battery terminals.
Any thoughts? TIA

Bad battery.
 
Try cleaning all of the ground cables. I even run and extra battery cable from the starter to the frame on my units as a back up. When you try to start the engine check the battery cables for heat. If there getting hot you most likley have a bad ground.
 
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Thanks for the imput guys and I will relay these ideas. Happy New Year!
 
If the battery is good, check both battery cables. Check them each on both ends where the wire is bared and goes into the crimp or terminal. I've seen corrosion get in between the crimp fitting and the wire letting very little current pass.
 
New battery and cables and starter and solenoid. All connection points are shiny metal. Same thing slow, very slow turn over.
 
A friend has this SC252 and just called with starting issues. Machine is in a warm garage. When he hits the start key the motor turns over very slow and would catch this summer. He has had the starter cleaned and rebuilt along with the celliniod and put on a new start switch. It still turns slow even with a charger/starter pack on the battery terminals.
Any thoughts? TIA

New battery and cables and starter and solenoid. All connection points are shiny metal. Same thing slow, very slow turn over.

This does not leave too much in the line. I am not going to bother running out to look at my 252, but here goes.

You say new battery.. new cables, new starter and new solenoid.

Grab a voltmeter and measure the battery voltage (if you can get a meter). Should be around 12volts under no load.

Take the same meter, leave it on battery and crank engine.. see what happens to voltage.

If it does not drop significantly (and I mean down to 3 or 4 volts), then take meter and place across starter motor and then crank again. You will need two people to do all of this. Voltage should drop, but will or should be close to what you observed on battery terminals during cranking (will be slightly less but not much).

Either the battery is low in charge, dropping low during crank.. or there is in fact high resistance between the battery and the starter terminals. Not sure which, but that is most likely.

If the voltage is not in fact dropping at starter and you still say slow cranking..?? Check to see there is oil in the engine :)

Seriously, let me know how the above tests work and see where we can go.
 
Try taking the spark plugs out and see if it cranks any easier. Will take the compression load off, if it cranks alot easier it could be she's close to seizing up. Just a thought. Or take electric clutch cover off and turn crankshaft over by hand, big bolt holding electric clutch on. If you can barely crank it by hand it's definitely something seizing up, if it turns freely, esp. with the plugs still out, must be in the starting system somewhere.
 
EVERYONE thanks. He and than I and his father started to really look this thing over. The FIRST thing he did is take the starter in for a rebuild and they did(?). I thought it was new before I got there. After a whole lotta stuff went back to the starter and started looking at it. Took it to a different guy and low and behold it was bad, still. He rebuilt it and we put it back on and all is wonderfull. Sucks that he/we had to go thru all this but on the flip side it is really cleaned up for when the stumps reappear from under the snow.
Again thanks to everyone for the imput.
 
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