by passing starter solenoid

[neighborbill]

Let me explain how I came to my conclusions.
A few years ago I put in the new starter motor with the solenoid attached on top.
Now what is happening. The signal voltage energizes the solenoid but the motor does not spin. I am getting 12 volts to the starter but when the signal is applied and the pinion kicks in there is no voltage showing up on the lower lug which leads to the starter motor itself.
I used a starter switch to jump 12 volts to the starter motor. Turned on the key, pressed the starter switch and it starts right up.
So the contacts in the solenoid can't be making good contact. I purchased a new solenoid but I'm going to have to remove the starter to put the solenoid on.
However, before I go through all the problems of getting it out and putting it back, here is what I'm going to do.
I have a three post solenoid. I am going to mount it near the starter. Run the battery B+ to that solenoid post. And then out the other post to the starter motor. Next make a parallel connection from the signal wire to the three post solenoid and to the old solenoid so that the pinion will energize.
Sounds like a lot but it isn't. Much easier then removing the starter and all that other gear to get the access.
What do you think?

 

[Forest#2]

That sounds like it's might work ok because you are still using the starter's existing solenoid as the shift bendix gear mechanical and the add on solenoid's CONTACTs in parallel with the starter's solenoid contacts.

Make sure you do not use a wimpy China type add-on solenoid. The reason i say this is I've had issues with the cheaper China solenoids contacts welding closed and ruining starters. (starter will stay engauged after the key is turned off and cannot be heard with the engine running)
Also mount the add on solenoid so as it's shielded from rain water.

You can easily test such before making a permanent mount.
Next time going into the machine replace the complete starter. I've had good luck with replacement starters from DB electric.
I re-build small engine starters but in your case I would not even trust a re-built starter for long life since it's hard to get to labor wise, go with new type.
Report back with your results.

 

[neighborbill]

I bought that starter from DB Electric a few years ago. Just surprised to find out about the contacts. Sooner or later I'll get it out of there and see what is up with those contacts.

What I am doing is basically jumping the old contacts

You are right about the continuous run on the starter motor if the contacts stick. I'll watch for that . Thanks for that tip.

 

[StarTech]

Also make sure the voltage at trigger terminal is not dropping a lot. ON some mowers I have to add a helper relay due long trigger wire runs causing voltage drops that only partially energizes the solenoid thus it sounds like it is working but it not fully engaging.

 

[Forest#2]

Also keep in mind that with the some electric mechanical shift bendix type starters that due to the mechanical design the solenoid en-gauges/shifts the bendix pinion gear into the flywheel slightly BEFORE the starter motor starts spinning (slightly before the solenoid contacts make to spin the starter motor) and reduces chance of flywheel teeth and bendix gear teeth wear which is a good design. The bendix is not spinning when it first en-gauges the flywheel teeth. (as compared to the other types that has the starter spinning and the starter pinion gear is already spinning as it en-gauges the flywheel ring gear teeth)
Your starter motor and bendix pinion gear is going to be already spinning as the gear is moved towards the flywheel teeth when you add your external solenoid.
Keep a heads up and do not ruin your flywheel ring gear teeth.

A good reasonably priced add on heavy duty solenoid type starter relay is the old fender mounted FORD starter relay. They can be used as the three terminal type even though they have 4 terminals and the frame of the case on most has to be grounded and they are almost bullet proof.

I would have mentioned this sooner but my internet went down for awhile.

 

[wb3czi]

I have read and have removed and replaced a starter motor on a BX1500 Kubota.
It is a nightmare because of room spacing.
I know now that the contacts on my solenoid are not making good contact when I try to start.
Without trying to remove the starter again. Here is what I am thinking of doing.
Buying a three terminal starter relay. connecting the B+ from the starter motor to the B+ on the new relay.
Then connecting the other side of this relay to the starter motor. Effectively by passing the contacts in the solenoid.
I will make a parallel connection to both the new solenoid and the old solenoid. This will engergize the plunger to the fly wheel. and at the same time close the new solenoid contacts.
When the motor starts, pinon falls back 5 volts to solenoids (because the starter switch is disengaged) is broken and the motor starts.
What do you think.

I did the VERY SAME THING on an old Toyota pickup. It'll work fine!

 

[RevB]

https://www.mytractorforum.com/threads/replace-starter-on-kubota-bx1500.1349145/

 

[neighborbill]

I did the VERY SAME THING on an old Toyota pickup. It'll work fine!

Thanks for the comment
I previously said "5 volts", I meant "12 volts"

 

[Gym123]

Did you test the starter after pulling it?

 

[VRR.DYNDNS>BIZ]

Excellent,
then what I am going to do, will work.
All this because it is so difficult to remove the starter and solenoid from the Bx1500.. Clearances are almost impossible without removing a lot of parts.

You indicated there is a solenoid on the starter. As you were already told, the solenoid shifts the drive into the flywheel, thus you cannot eliminate the solenoid. Take the advice of someone who has rebuilt thousands of starters. if it is a Denso starter, the contacts may solve it. If you replace the solenoid on another design/OEM starter it may resolve it.