G1900 - sticking starter solenoid?

   / G1900 - sticking starter solenoid? #1  

Sniggle

Silver Member
Joined
Jan 27, 2008
Messages
234
Location
Jefferson County, WV
Tractor
2003 Kubota B7800 (new to me @ 435 hours
My g1900 starts fine sometimes, but other times I need to use a portable lithium ion jump battery. When I use the jump battery, when she is being stubborn, regular mode will not start the motor, but if I put the jump battery to extra boost she starts right up. It does appear to be a replacement starter motor, put on before I bought the lawn tractor 16 years ago.

My guess is that the starter motor solenoid sometimes sticks, and it takes the extra boost from the jump battery to get it moving. Does this sound right?

My plan is to pull the starter after the last lawn cutting, and see if I can clean up the solenoid....or possible just put on a new stater motor, unless you folks tell me I am barking up the wrong tree.
 
   / G1900 - sticking starter solenoid? #2  
Did you get a voltage reading of the battery, engine not running/running? Check connections?
 
   / G1900 - sticking starter solenoid? #3  
Clean battery terminals and cable ends. Check carefully for corrosion. Replace cables and tighten securely. Follow ground lead to frame. Clean and tighten. Check battery voltage and charge if needed. Monitor battery voltage while attempting to start. You could have a defective connection or a too old battery.
 
   / G1900 - sticking starter solenoid? #4  
A quick image search indicates that it should have the starter with the can solenoid on top. If it just clicks and clicks and the boost finally engages it, chances are that the big square head copper bolts that the battery cables attach to have eroded and carboned up to where they don't make good contact any more. You can either replace the solenoid, or be cheap like me and carefully take it apart and rotate the square heads so the plunger disc hits the new side.
 
   / G1900 - sticking starter solenoid? #5  
First off make sure you have a good battery and charging system. The fact it's starting with a booster tells me you have issues
 
   / G1900 - sticking starter solenoid? #6  
In our repair shop we must have done dozens - maybe hundreds.... of "starter won't turn" repairs. Most of them were not in the starter at all. If the battery and cables were OK, it was generally that the solenoid's internal copper contacts needed some attention with sandpaper and file. Not always, but that is where to look first.

The ones where the starter motor itself needed attention often came in with the same story:
Someone had taken off the original starter motor and then instead of rebuilding the OEM starter, it was replaced with a cheaper generic - often a rebuilt - from a parts house.

rScotty
 
   / G1900 - sticking starter solenoid? #7  
Very common on G1900 tractors. I'd clean all connections. One thing to check is the voltage to the solenoid, they are notorious for not having good voltage at the solenoid. Some have added an extra relay to send power to the solenoid.
 
   / G1900 - sticking starter solenoid?
  • Thread Starter
#8  
I tore the starter down today (armature side). It had some dirt and grime on most of the surfaces, which I cleaned. I lightly sanded the brushes and the copper body, as well as the interior field coils (2nd picture), which were a bit pitted. I pushed in some more grease into the bearings, and put a light coat of oil on rotating surfaces.

The only challenge (besides losing a dam screw for the top of it...aaarrgghh) was getting the armature back in the brushes, which are spring loaded. After flailing for a bit, I found that a gas can spout worked great (after I cut the lip off, 3rd picture) to push apart the brushes and let me push the copper body in.

I reinstalled it and it seems to work....3 for 3 in my test start ups. Time will tell if I solved the issue for good:) If this does not solve it I will get into the solenoid side next.
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   / G1900 - sticking starter solenoid? #9  
As noted earlier, check your voltage to the solenoid. I ad this issue and even went so far as to install a whole new starter BEFORE I took time to check the voltage. I found it was only about 10V. I went through every safety switch on the machine, even eliminated some. Still no bueno. I finally threw in the towel and modded the machine with a helper solenoid. Pretty sure I did a write up of it on here. If not post back and I will post a part list and photos. Now no issues at all
 
   / G1900 - sticking starter solenoid? #10  
Very common on G1900 tractors. I'd clean all connections. One thing to check is the voltage to the solenoid, they are notorious for not having good voltage at the solenoid. Some have added an extra relay to send power to the solenoid.
Ding-ding-ding! Just added a "helper relay" to our G5200 and also removed the flywheel to inspect the gear teeth. Some of the teeth had substantial raised burrs. I used an abrasive wheel in my Dremel to deburr the teeth and now it starts on the first or second crank. I believe that low voltage, due to accumulated resistance from several safety switches resulted in the solenoid not fully engaging the starter pinion / ring gear mesh, beating up the gear teeth. This resulted in a self-stoking cycle of increased mesh resistance causing reduced mesh engagement causing increased gear wear until everyone just quit. I'll post details of the repairs if anyone asks.
 
 
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