Starter grounding

[leeroy]

Hyacinth had not been started in a month or so, and when a start was attempted there was nothing but a solenoid click. Battery and solenoid good. Jumped spare 8n starter to rule out solenoid.
Direct jumped the Fordson starter off running tractor and also on running truck with no spin.
Took starter apart to look for issues. Did a light cleaning, brushes good and armature passes the 3 ohms tests that are commonly suggested.
When I put it back together the case has a ground. This is off the tractor. Tested with battery and test light as well as multimeter. It only grounds when one of the two brushes attached to the end plate is released to contact the commutator.
I can have the three other brushes where they should be with no short, but that last one causes the short. I will be looking closer as that brush and holder, but curious if there is something I could be missing. Could it be that the pinion side is not on and the armature is contacting the field coils?
Hoping for a simple fix as only local repair shops, which are not that local, don't sound very confident on sourcing Lucas parts here in the states.

[Billy26F5]

That sounds odd, as the two brushes on the plate are earthed, it's the field coil brushes that need to be insulated. Check the field coils using the test light and make sure those brushes are in the insulated holders (clearly distinguisheable by having insulation in the mounting rivets). You shouldn't be in trouble for parts (although I'm hoping you can fix this with no new parts). I'm wondering if the insulation in one of the insulated holders might be bad, but that would require a new insulating bush and rivet.
Sandy

[leeroy]

Ok I see that now. I am getting ready to check it over again and will report back.

[leeroy]

I put it back together but no luck. I had it on board and jumped it from a running truck. Sparks and looking close the armature was barely turning. Everything is free on the pinion side so I fear there is an electrical problem beyond my knowledge.
I did make sure the wires for the field coil brushes were not touching case for what that's worth. Some smoke from starter as well.

[Hair Bear]

I don't know who to attribute this to, but could apply in your case...

Positive ground depends upon proper circuit functioning, the transmission of negative ions by retention of the visible spectral manifestation known as "smoke". Smoke is the thing that makes electrical circuits work; we know this to be true because every time one lets the smoke out of the electrical system, it stops working. This can be verified repeatedly through empirical testing. When, for example, the smoke escapes from an electrical component (i.e., say, a Lucas voltage regulator), it will be observed that the component stops working. The function of the wire harness is to carry the smoke from one device to another; when the wire harness "springs a leak", and lets all the smoke out of the system, nothing works afterwards. Starter motors were frowned upon in British Automobiles for some time, largely because they consume large quantities of smoke, requiring very large wires.
It has been noted that Lucas components are possibly more prone to electrical leakage than Bosch or generic Japanese electrics. Experts point out that this is because Lucas is British and all things British leak. British engines leak oil, shock absorbers, hydraulic forks and disk brakes leak fluid, British tyres leak air and the British defense establishment leaks secrets...so, naturally, British electrics leak smoke.

[Billy26F5]

Brian posted this ages ago, it might be the case, but I suspect it's probably the insulation for one of the insulated brushes. Try it with the offending brush off the commutator and see if it's any better, I would suspect if the insulation has failed the current was all missing the armature and leaving it with no torque. The smoke suggests a really high current, lots more than the 450 amps specified in the manual. If it does work with the brush off it will have less than half the normal torque but should turn ok.
Sandy

[leeroy]

I don't know who to attribute this to, but could apply in your case...

Positive ground depends upon proper circuit functioning, the transmission of negative ions by retention of the visible spectral manifestation known as "smoke". Smoke is the thing that makes electrical circuits work; we know this to be true because every time one lets the smoke out of the electrical system, it stops working. This can be verified repeatedly through empirical testing. When, for example, the smoke escapes from an electrical component (i.e., say, a Lucas voltage regulator), it will be observed that the component stops working. The function of the wire harness is to carry the smoke from one device to another; when the wire harness "springs a leak", and lets all the smoke out of the system, nothing works afterwards. Starter motors were frowned upon in British Automobiles for some time, largely because they consume large quantities of smoke, requiring very large wires.
It has been noted that Lucas components are possibly more prone to electrical leakage than Bosch or generic Japanese electrics. Experts point out that this is because Lucas is British and all things British leak. British engines leak oil, shock absorbers, hydraulic forks and disk brakes leak fluid, British tyres leak air and the British defense establishment leaks secrets...so, naturally, British electrics leak smoke.

Funny Hair Bear! Ironically I stumbled on that while searching the web yesterday!

[leeroy]

Brian posted this ages ago, it might be the case, but I suspect it's probably the insulation for one of the insulated brushes. Try it with the offending brush off the commutator and see if it's any better, I would suspect if the insulation has failed the current was all missing the armature and leaving it with no torque. The smoke suggests a really high current, lots more than the 450 amps specified in the manual. If it does work with the brush off it will have less than half the normal torque but should turn ok.
Sandy

Thanks Sandy, I look forward to trying this!

[leeroy]

Spent some more time with the starter. I used some plastic pieces and tire tube pieces to insulate any questionable points.Confident the plastic insulator for the positive post on cover is good.(set up as negative ground here).
Tried again on jumpers off running truck. Got a slow spin along with "leakng" smoke and some heat.
Then I pulled one of the insulated brushes, tried again and got great spin! Was just coming in to ask how to proceed, whether to cot brush right off etc. Decided to put brush back in just to be sure and it spins fine?!. I repeated this over on the two insulated brushes and got the same results. Noticeable torque difference with one brush removed.
So I plan on putting it back on Hyacinth and seeing what happens. Not quite sure what helped here. I'll post a picture of my insulating, and hopefully a running Hyacinth!

[Billy26F5]

Looks like one of these strange problems after all, just make sure the insulated brushes are nicely insulated when you close everything up.
Sandy

[leeroy]

My memory, or lack of has caused some trouble. When Hyacinth failed to start, I checked voltage and it was 12.5. I then tried a start and it dropped to 3 volts! I pulled the battery and one cell was very low. I topped it off with battery electrolyte and slowly charged it up. It was a few days before I tried again and became convinced it was not the battery, but the starter. When I got no spin direct to starter even more convinced. But I forgot to mention I cleaned up my jumpers before I got a spin. When I put it back in Hyacinth after successfully jumping it, but getting nothing, I finally remembered the battery fault at the "start" of all this! Hopefully some of the work I did will help. I know my way around a starter now! Bet I had it apart apart 7 times! I'll try to remember to follow up here when a good battery is in!

[Billy26F5]

No wonder it didn't work at first. The other problems are odd, but you've saved the starter very nicely.
Sandy

[leeroy]

Although winter is coming I stole the battery from our plow truck. It too had a low voltage. I did not try to start the truck(Dodge with 6cyl Cummins) instead took the time to clean up and charge battery. Both batteries had one cell with .6 volts and hydrometer reading 50% while other cells showed 75%. I emptied and added Epsom salt to the bad cells in each respective battery, then slow charged at 2 amps for a few hrs at a time. Even though the battery cases looked clean and dry I got voltage readings all over the top. Research suggested cleaning off battery with a baking soda solution. I did, and feel this made a big difference in the batteries accepting and holding a charge. I put the battery from the plow truck -which was now holding 12.7-
Into Hyacinth and she started great! Fastest turnover ever. Both batteries ar group 31.
I've yet to put Hyacinths battery into the Cummins but will report my findings.
Also had a big battery that has been sitting out for some time. 4dlt group. Came out of our 3600.
It was only a few years old when it got too weak. I'd put it on the charger and get it to 12.4 but no higher. Voltage would drop over night. Yesterday I tested the voltage all over top of battery and was getting high readings. So I cleaned it with baking soda and dried it off with same good results: charged to 12.7 and did not drop off after a few hours.
I'll check these three batteries this morning after resting all night.

[Billy26F5]

A dirty top is always bad, especially when electrolyte leaks. Glad they're fine again.
Sandy