Removing 1974 Starter Motor from V8

SydneyRoverP6B

Well-Known Member
Staff member
My Rover has an issue with it's starter motor. In the past when I turned the key and only heard the latching of the starter relay up on the inside guard, I would reach for the rubber mallet. A few short sharp strikes to the starter solenoid and she would fire at the next turn of the key, but not this time. I have tried without success over and over, the starter solenoid continues to click, but there is no life from the starter motor. I know that there is current flowing to the solenoid as if I place a steel socket wrench against the solenoid whilst the key is being turned, I can feel the magnetic field grabbing the wrench.

The starter is 46 years old and is the original that came with my Rover, so I can't really complain if it needs new brushes or such like.

What do you think it sounds like? Can I remove the starter without dropping the downpipes, or is there a clearance issue? I know it is just two bolts that retain it to the block, but I don't have all my tools with me, so the less I need to do the more convenient it will be.

Thank you!

Ron.
 
It's either the mechanical side or electrical. The mechanical side is the lever throwing the gear into flywheel rack or the gear on the shaft 'sticking'. the electrical side is the contacts in the solenoid are dirty. With your limited resources you could try taking solenoid, which is easier to wangle out than the starter, off the starter so you can check which side it is. My money would be on the contacts being dirty which you can clean up after taking the cap off the end on the kitchen table bench. ;)

Colin
 
colin is correct, although theres a chance the fault is a bad connection where the main power cable comes through the floor under the drivers feet
 
I thought I had a dodgy starter solenoid the other month, turned out to be dodgy wiring at the reverse inhibitor switch (on the remote of the LT77 my car has). I can't remember if your car is an auto or manual, Ron. Good luck. Keep us posted!
 
Try taking the engine earth wire off first, give it a good clean with some sandpaper, and where it fits onto the body/engine.

That might work
 
often a solenoid issue as they get sparking /contact resistance on contacts but DO check loose wires. corrosion .poor earthing etc looks as though you knew you had solenoid issues and were winging it .
 
Thanks Gents for your replies, I really appreciate your thoughts and suggestions!

When the ignition is turned to position 4, I can detect the magnetic field within the solenoid with a spanner on the outside. Does that mean that the contacts have closed and current is flowing, and if so, does that mean that it would not be the solenoid contacts or could it still be them?
Certainly taking the solenoid off first would be easier, and I could clean the contacts then refit and see what happens. If no joy, I could then remove the starter.

Being in Australia, I have never had corrosion problems with wiring, so although not impossible it is probably unlikely. Still, I can check though.

I am glad that I can take it off Harvey without the need to drop the downpipes, makes it a little easier. Yes and I certainly agree, it will be heavy!


Ron
 
If it's original, the contact points on the solenoid are likely well burned up by now. Arcing, not corrosion, is the death of most high current contacts.

Yours
Vern
 
I can detect the magnetic field within the solenoid with a spanner on the outside. Does that mean that the contacts have closed and current is flowing
No. The magnetic field you are detecting is used to move iron core of the solenoid. This core should move (the clunking sound) and contact the internal terminals, which provides the high amperage for the starter motor.
The magnetic field can be detected without the contacts closing; the core could be stuck, the terminals dirty or terminals spark eroded to the point where they don't contact.

Here is a great troubleshooting guide. Starter Solenoid: The Definitive Guide To Solve All the Solenoid Problems

If you put a cheap or unwanted spanner across the two heavy terminals of the solenoid (sparks will fly) and the starter turns strong then your solenoid is the issue.
If it is the solenoid, as always, check for good earth from the engine and a good feed positive feed from the ignition switch. To check if it is the ignition switch, press a wire straight from the battery to the ignition switch terminal on the solenoid. Even then it's probably still the internal contacts.

If it's original, the contact points on the solenoid are likely well burned up by now. Arcing, not corrosion, is the death of most high current contacts.

Even if you find the solenoid works again after fiddling, i.e. if the internal contacts where to blame, I'd still replace the solenoid with a new one. As Vern Klukas said, they do wear out.

G.
 
No. The magnetic field you are detecting is used to move iron core of the solenoid. This core should move (the clunking sound) and contact the internal terminals, which provides the high amperage for the starter motor.
The magnetic field can be detected without the contacts closing; the core could be stuck, the terminals dirty or terminals spark eroded to the point where they don't contact.

Here is a great troubleshooting guide. Starter Solenoid: The Definitive Guide To Solve All the Solenoid Problems

If you put a cheap or unwanted spanner across the two heavy terminals of the solenoid (sparks will fly) and the starter turns strong then your solenoid is the issue.
If it is the solenoid, as always, check for good earth from the engine and a good feed positive feed from the ignition switch. To check if it is the ignition switch, press a wire straight from the battery to the ignition switch terminal on the solenoid. Even then it's probably still the internal contacts.



Even if you find the solenoid works again after fiddling, i.e. if the internal contacts where to blame, I'd still replace the solenoid with a new one. As Vern Klukas said, they do wear out.

G.

Thank you indeed for your advice and the link, very much appreciated Gargo!

Ron
 
Today I checked the supply to my starter motor prior to removing it from the engine. I measured 12.5 V between terminal B (30) and an Earth point. This terminal has an unfused permanent connection with the battery, so having battery voltage at this point provides reassurance that my Rover's wiring is not at fault. I also measured 12.5 V between terminal S (50) and Earth when the ignition switch was moved to position 4. This was accompanied by a heavy thud within the solenoid and the mechanical rod moved with the application of the magnetic field. This was also accompanied by a loud click but no engine start.

I checked the continuity, as detailed within the attachment kindly provided by Gargo. It appeared between S & M and again between M & B, which the article advises as being demonstrative of a troublesome solenoid.

I removed the starter motor complete and will take to an Auto Electrician on Monday. From the people at work that I have spoken to, he is very much 'old school' so has the ability to test and repair old pieces of equipment.
In the meantime, here are some photos of today's little exercise. One thing that I noticed is that the starter gear that engages with the ring gear was locked solid. I could not slide it out, which I assumed would be possible. Should it slide or is being locked in position normal?

20200516_114330.jpg20200516_121206.jpg20200516_122132.jpg20200516_122203.jpg20200516_122230.jpg
Ron.
 
I collected my starter motor on Thursday afternoon, refitting it today, with it preforming just as it should, starting the engine beautifully! :D. It had a number of problems, the main two being a short within one or more of the field coils, and a short to Earth within the armature. The former was corrected by removing and retaping the field coils. On the end of the armature there is a band that was cut off which allowed the windings to expand slightly. As a means of providing insulation and rectification of the short, araldite was generously applied over and between the windings.

The brushes which are an unusual triangular shape and quite different to the brushes used within Australian made Lucas starter motors were left. They are worn and will need replacing before too many more years pass. The smaller of the two springs within the solenoid was replaced as it was quite distorted. The contacts surprisingly did not require replacement, as they were still in good condition.

Ron.
 
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