Jacobsen 628 2wd

snakeknuckles

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So I bought my 628 2wd at auction in upstate ny- ended up spending 3k. Machine is fast and quiet and nice ride. My other finish mower is a 422. My 422 bogs easily... the 628 sucks in the traction department. Traction brakes need work but I plan on retrofitting a diff lock valve. The Jacobsen difflock lists for 2300... Bûcher makes one that i am told is much cheaper. Anyone know the pump output on this machine- 20l/min?
Also need to convert rear discharge to side for my cyclone rake. Should just be sheet metal work?
 

BlazNT

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Rear discharge spins one blade in the opposite direction. You will have to re-engineer the deck to get it to side discharge.
 

northcreeek262

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I don't understand how a differential lock would work on the 628 since there is no differential. Unless your machine is different but, my 628 has a hydraulic motor on each wheel....Mike.
 

snakeknuckles

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On the rear discharge issue, I will compare my 422's deck to the 628... It might be easier to move that deck to the 628- It looks much heavier than the one on the 628. It also does not have sealed bearings. It sounds like the 628 blades spin faster than the 422.... On to the diff lock saga: In response to northcreek262's question about a differential- I know we are all used to a differential gear set being the way to make inner and outer wheels to be driven "differentially", but a single hydraulic motor driving to equal motors in parallel also works perfectly as a differential. There are two types of flow dividers that effectively drive both wheels at same rpm regardless of load(pressure); they are pressure compensated and rotary gear type. based on the schematic in the jacobsen parts manual (and the price), I think the one Jacobsen sells is a rotary gear type- probably a Parker? Does anyone know? The one I am looking at is a pressure compensated valve manufactured by Bucherhydraulics:
see:
https://www.bucherhydraulics.com/47...-functions/Differential-lock-valve/index.aspx

I am trying to price the thing out and get more info but the Bucher dealers I have talked to so far are clueless. Anyone know a good Bucher rep?
 

northcreeek262

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Aug 21, 2018
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On the rear discharge issue, I will compare my 422's deck to the 628... It might be easier to move that deck to the 628- It looks much heavier than the one on the 628. It also does not have sealed bearings. It sounds like the 628 blades spin faster than the 422.... On to the diff lock saga: In response to northcreek262's question about a differential- I know we are all used to a differential gear set being the way to make inner and outer wheels to be driven "differentially", but a single hydraulic motor driving to equal motors in parallel also works perfectly as a differential. There are two types of flow dividers that effectively drive both wheels at same rpm regardless of load(pressure); they are pressure compensated and rotary gear type. based on the schematic in the jacobsen parts manual (and the price), I think the one Jacobsen sells is a rotary gear type- probably a Parker? Does anyone know? The one I am looking at is a pressure compensated valve manufactured by Bucherhydraulics:
see:
https://www.bucherhydraulics.com/47...-functions/Differential-lock-valve/index.aspx

I am trying to price the thing out and get more info but the Bucher dealers I have talked to so far are clueless. Anyone know a good Bucher rep?

Thanks for taking the time to explain that . I'm ok in the electrical field but, hydraulics...not so much...,Mike.
 
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