It's a little gem

WadeGJ

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Hello world. I'm in Melbourne Australia. I have been "gifted" a Bolens ST125 Suburban Hydro that has been left out in the weather for the past 3 years.
I have replaced carby and magneto as they both were rusted away. Cleaned fuel pump and fitted new fuel filter and spark plug. Now engine runs.. :) replaced main drive belt with a Kevlar series, but I'm thinking it's a few inches short..When I press brake lever and release, it's not travelling far enough forward to release rear brake, so disconnected for now.. When I release brake slowly engine wants to stall while pedal is in neutral .. I can make the forward/reverse pedal engage slightly before it stalls....
I raised rear wheels off the ground to check and see if rotation was going to happen.. This is where I'm at and end.... Am I correct to assume engine throttle linkages are not correct and not rear end at this stage. Cheers
 

WadeGJ

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I failed to mention that the deck is not attached currently..(that's another story) Just trying to run without it..
 

bertsmobile1

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Welcome
When you apply a load to the engine the throttle should open wider to compensate for the load.
If not then the governor needs adjusting
If it was left in the weather it could even be rusted away .
Knowing what engine is fitted would be a help .
If the brake is external pull it off the tranny by removing the two bolts at the end of the caliper , do not touch the center one that is the adjuster .
The brake has 2 pins which will rust solid in position and the disc will rust onto the spline as well ( it is supposed to float ) .
As for the belt, if it loosens enough for the belt to slip on the engine pulley without burning then it is not too short .
The brake is activated by a rod and that rod will have an adjuster ( usually spring loaded ) where it connects to the clutch mechanism, this is where you adjust the balance between clutching & breaking
The brake should come free just as the belt starts to spin.
Too late and it will pop wheelies whenever you take your foot off the pedal & too soon will allow the mower to roll ( backwards some times ) before the clutch takes up.

The brake rotor is on the layshaft which locks the diff so the wheels can only turn in opposite direction ( same as Park on a car auto tranny ) so it has 2 positions, full on or full off .

After you free up the brake & adjust the balance then you adjust the centre nut on the caliper if needed
If the wheels turn in opposite directions when they are off the ground & the mower is in drive or reverse, that is the typical symptom of a stuck or frozen brake.
I have a copy of the mower manual but it is too big to post on the forum ( 4 Mb ) so if you PM me with our email address I can send you copy .
From memory they had a Kohler engine and Kohler have all of their engine manuals on the USA koher site.
Don't bother even trying to use the Australian web site as like most OZ ones it is just there to allow you to down load the BS catelogues .
As for the deck, probably the most complicated set up I have ever seen, designed to use PLAIN belts and to keep the belt run in the proper plane as you raise & lower the deck .
First one I changed took 2 hours .
 

WadeGJ

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bertsmobile1
Thank you.
The engine is a 12.5 hp IC B&S single. I removed the lever at the pivot point (taking your advice not to touch adjuster. Wheel lifted off the ground wheels turn freely when the lever underneath is set to freewheel and engaged mode.
AAAh the deck. The tensioner for the pulley was badly rusted on that I used angle grinder to cut a slot to remove it. Polished shaft and regreased.. works a treat now but the shafts with blades will need replacement as the blades/bolts are so rusted on.. But will come after I get the "old girl" moving first.. :). Now I will take your advice and focus on the governor.
gregandman1@gmail.com
Cheers
 

WadeGJ

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Hi group.. Chasing seat switch question. It appears that previous owner had cut off switch and just crossed the wires.. Does it require a resistance, even hot wired? I read someone used a diode to cross wires.. Help please..
 

bertsmobile1

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Generally no
either normally open or normally closed
and some times both if there is a 4 pin plug .

I don't have a circuit diagram for your mower so can not be definate buy either on or off will be the go
Mowers are not that sofisticated
 

WadeGJ

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Generally no
either normally open or normally closed
and some times both if there is a 4 pin plug .

I don't have a circuit diagram for your mower so can not be definate buy either on or off will be the go
Mowers are not that sofisticated
Thank you.. I'll now move onto wring issues and try to bypass brake switch as well
 

WadeGJ

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Well thank you all.
I was able to download an instruction manual... while trying to chase what we believed to be an electrical issue... bingo
The redundant seat switch was hot wired together......according to diagram it remains "closed" until sat upon....Separated wires and bingo... we have great little gem that drives and cuts like a dream....
Now we focus on little issues like steering slack , oil changes etc
Thank you again group!
 

WadeGJ

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Hi guys, Bolens ST125 is up and running... Somewhat amazed that it doesn't have an oil filter, but, the bolt on bottom of oil drain is seriously locked on. Afraid too much force will snap something. Using SAE30 oil. and drawing it out using old turkey baster.... NOW what do you suggest for the hydrostatic in the rear. Some have suggested using same SAE 30 ( Penrite here in Aust) If it has to be SAE 20.. what rating?
Thanking you all again.
 

WadeGJ

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I failed to mention that its an EATON 750 Transmission
 
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