Belarus 310 Starter Solenoid wiring

I have a Belarus (Pray) 310 Tractor. I've been trying to rewire the
starter solenoid. The coil works fine, but the wiring to the coil is
all corroded.

When I tried to get the coil to throw the solenoid by hooking it up
the way I thought I should, I get nothing; that is connecting the
body/ground to negative battery, and the power connection to to
positive battary; nothing happens even when you short the starter switch/relay stud to positive..

If you take the cap that holds the electrical connectors off the
coil, you see that there are only two connections going into the
coil. One which goes to the starter relay/switch stud actually
has two wired connected together which go into the coil. The
other wire goes to the positive battery power.

The only connection I found to make the solenoid coil react is
connecting the two wires going into the coil to positive and
negative battery. Then the solenoid goes off!

This doesn't make any sense to me because the one wire goes
to the main battery positive power stud; the two wires that go
into the coil together go to the starter relay/switch!!!

Now I've paid to have this starter 'rebuilt' a couple of times;
it didn't seem like they were really doing anything because it
fail within a years again. So I decided to clean it up myself.
Maybe it's wiring is no longer original?

It doesn't help that you have to unsolder a couple of connections
just to get the cap off, and there's no way to put it back together
because the starter relay stud is soldered to a wire with no slack.
I put a ring terminal on the starter relay stud under the cap on a
wire a couple inches long to give me enough slack to push the
relay stud through the cap and then screw the cap on, and solder
the ring terminal outside the cap on the main power stud to the
wire that goes through the cap to the ring terminal.

Is it supposed to be like this? Has this already been screwed over
sometime in the past?

Thanks, Jaimes Beam

I'm not familiar with your model,but have worked on a couple of larger Belarus' with starting problems.It may not be a solenoid per say, you may have a series parallel switch. Tractor starts on 24 volts but runs and charges 12 volt. Does your tractor have 2 batteries? I used a series parallel switch for an older Mack. I had to look up an old (1960's)truck manual to figure out to wire it up.

As far as the wires being connected inside the solenoid the way they are that is correct. There is actually 2 windings in a solenoid like that and thats how they are done. The thing I want to make sure of though is that the one wire connection from the solenoid winding goes to the field stud not the battery stud. maybe thats what you meant and I misunderstood. if you take an ohm meter and measure from the switch stud to ground ,then to the feild stud, then fom the field stud to ground you should get connection to all those points. If you have this then the solenoid coil is "probably ok". then you have to look at how much your big studs are burnt off or how bad the moving contact is. hth jstpa

Thanks for the reply!

Let me try to respond to your comments:

The single wire that goes into the solenoid coil is connected to
the stud that is connected to the battery.

The two wires that are connected together that go into the
solenoid coil are connected to the smaller stud that goes to the
starter relay or starter switch.

The other large contact stud goes to the Starter motor through
a little strap.

If I take a ohm meter and measure from ground to either the
battery power stud, or the starter relay/switch stud I get a few
ohms; likewise between the two studs.

I can't make this make sense in my head, thinking that the body
is negative ground what it's on the tractor, batter power goes
to the one big stud, and when you apply power the the relay stud
the solenoid fires and connects the moving contact inside with
the battery stud contact to the starter motor stud contact to run
the starter motor???

The moving contact works fine; I tried it out on my workbench;
in a vise. If you're not carefull you could put a hole in something
/someone!!!

Thanks, Jim.

My Tractor has two 6 Volt batteries, and a 12 Volt starter etc.

Where's the ground strap from the cab to the engine? I've already
replaced the Ground Power On/Off switch on the firewall. I think
my ground strap is bad.

The other weird electrical thing about the tractor is that the fuses
are wire wrapped around a card mounted on the front of the firewall!!! None of the electrical stuff works anyway... :-(

Thanks for the response, Jim.

No parallel switch on a 310,this is the smaller two cylinder tractor,12 volt.

Those fuses are what they call "lifetime" fuses.When you blow one,swing the blades to the sides,unwind a little wire off and replace the blown piece of wire.Swing the blades back straight and reinsert.Very cost effective fuse.

Also,double check your grounds.250/310's are known for ground issues,esp. between where the ground switch mounts to the cowling.

Jaimes, it sounds like the windings are good. But the bigger stud with the little wire on it should go to the starter strap not where the battery wire goes on. When you hit the key switch you put juice to the switch stud. the juice goes though the pull in winding out the field stud through the fields and brushes to find a ground. that puts the contact across the 2 big studs which puts juice to the starter fields and then the winding in the solenoid finds it ground through the 2nd winding, which is the hold in winding. thats a rough explanation of how it works. There are probably people on this site that could probably give you a better explanation. hth jstpa

OK, Thanks, I think I understood that!

Yes, I had the two big studs reversed; I had convinced myself that
the Stud with the coil lead on it had to be the battery stud instead of the Starter stud.

I'll try it out tomorrow and see if it works!

Thanks, Jim.

So where's the ground cable/strap? I have not been able to find it.

It has started better if I put a jumper cable from the battery negative to the engine block.

Thanks, Jim.