Starter motor solenoid dreaded click.

[rusty69]

1 minute ago, Sir Nibble said:

That's it. Not everyone appreciates that the solenoid has two windings, engagement, which is multo powerful and earth's through the motor and hold in which has its own earth. If the brushes fail the engagement winding doesn't work and all you get is a faint tick as the hold in winding does little more than line up the plunger with the coils. The fuse gives an alternative path to earth for the engagement winding, engages the starter and blows the fuse when the contacts close. The arrival of 12V usually recalls the brushes to their duty and amidst much sparking the motor cranks. 

Many thanks Sir nibs. I will try it tomorrow and report back. 

 

Good night kind sir. 

[Sir Nibble]

You're welcome. I did a dissertation on how alternators work on here once, god knows where it is now. I dread doing it for the cav co axial! If you know precisely how it works, you can usually work out precisely why it doesn't ?

[MtB]

18 minutes ago, Sir Nibble said:

If you know precisely how it works, you can usually work out precisely why it doesn't ?

 

That applies to everything, in my personal experience. 

 

Greenie for stating the beedin' obvious, but only bleedin' obvious once stated!!

 

?

[Sir Nibble]

8 minutes ago, Mike the Boilerman said:

 

That applies to everything, in my personal experience. 

 

Greenie for stating the beedin' obvious, but only bleedin' obvious once stated!!

 

?

I used to teach this stuff and always told my students that if you don't know how it works in theory you have fkall chance of working out why it doesn't work in practice.

[alan_fincher]

31 minutes ago, Sir Nibble said:

 If you know precisely how it works, you can usually work out precisely why it doesn't ?

Best sentence I have seen on the forum in a very long while!

 

[Sir Nibble]

Sorry about the brushes being "recalled to their duty" by the way. Temporarily possessed by the spirit of Steven Maturin.

[frahkn]

1 hour ago, Sir Nibble said:

Sorry about the brushes being "recalled to their duty" by the way. Temporarily possessed by the spirit of Steven Maturin.

 

There are many worse spirits to be possessed by IMHO.

[rusty69]

15 hours ago, rusty69 said:

Many thanks Sir nibs. I will try it tomorrow and report back. 

 

Good night kind sir. 

Ok. Update. Fuse holder with 20A fuse in between engine casing a starter motor. 

 

Result =fuse remained intact and engine didn't crank. The initial trial start resulted in boiiiiing type noise (like zebedee) before returning to the usual clunking. 

 

From this, i spose the solenoid contacts are the likely candidate? 

[bizzard]

11 minutes ago, rusty69 said:

Ok. Update. Fuse holder with 20A fuse in between engine casing a starter motor. 

 

Result =fuse remained intact and engine didn't crank. The initial trial start resulted in boiiiiing type noise (like zebedee) before returning to the usual clunking. 

 

From this, i spose the solenoid contacts are the likely candidate? 

Souds like them buzzing.   To rough test the actual motor run a jump lead from the POS+ post on the battery to the big terminal nut on the solenoid, the lower one with the uninsulated braid going into the starter body. The motor should instantly whip up to speed without engaging the ring gear.

Edited September 29, 2018 by bizzard

[rusty69]

7 minutes ago, bizzard said:

Souds like them buzzing.   To rough test the actual motor run a jump lead from the POS+ post on the battery to the big terminal nut on the solenoid, the lower one with the uninsulated braid going into the starter body. The motor should instantly whip up to speed without engaging the ring gear.

Just done that. The motor spins. 

[bizzard]

3 minutes ago, rusty69 said:

Just done that. The motor spins. 

Whips up to high speed powerfully ? if so it looks like those solenoid contacts.

Edited September 29, 2018 by bizzard

[rusty69]

Just now, bizzard said:

Whips up to speed powerfully ? if so it looks like those solenoid contacts.

Yep. 

 

Guess i will have to remove the starter from the engine again if the contacts are easy to replace. Failing that.... EBay here i come. 

 

Thanks Bizzard. 

[Sir Nibble]

I think those contacts can be removed and rotated 180 degrees to go again and the moving contact held in place with an "e" clip removed and turned over to present a fresh face. I will identify a new cap when I go to work on Monday and price it up.

[rusty69]

20 minutes ago, Sir Nibble said:

I think those contacts can be removed and rotated 180 degrees to go again and the moving contact held in place with an "e" clip removed and turned over to present a fresh face. I will identify a new cap when I go to work on Monday and price it up.

That sounds promising. Many thanks indeed. Just picked this up in the local chandlery for 20 quid. Dunno if it is the same, but worth a punt

[Sir Nibble]

The solenoid might swap if nothing else.

[rusty69]

1 hour ago, Sir Nibble said:

The solenoid might swap if nothing else.

A successful afternoon. The replacement starter not only fits, but works too hoorah. What are the chances of that! 

 

Have had a quick look at the old one off the engine. Any clues how it comes apart. 

 

Many thanks to all contributors. 

 

 

[rusty69]

[Boater Sam]

Congratulations rusty, 42 posts, no mention of a fan and no silly comments, I withdraw my request for you to shut up.

 

See, its better when you want sensible answers, so do we.

 

Please keep up the reformation! Sam.

[rusty69]

38 minutes ago, Boater Sam said:

Congratulations rusty, 42 posts, no mention of a fan and no silly comments, I withdraw my request for you to shut up.

 

See, its better when you want sensible answers, so do we.

 

Please keep up the reformation! Sam.

I wouldn't get too used to it. I am quite happy for people to jump in with some humour (i notice you are doing just that yourself with your astro turf comment, or were you serious? )

 

Generally i try and wait until an OP has had their questions answered before jumping in though! 

Edited September 29, 2018 by rusty69

[Sir Nibble]

Well, the replacement starter has the old style removable cap but the original has the later crimped on style which has to be pressed apart. I'm tooled up for that but it's now not at all certain that it's worth doing is it? 

[Boater Sam]

Serious, it would be lovely.

Glad you are mobile again.

Sam.

[rusty69]

49 minutes ago, Sir Nibble said:

Well, the replacement starter has the old style removable cap but the original has the later crimped on style which has to be pressed apart. I'm tooled up for that but it's now not at all certain that it's worth doing is it? 

Possibly not worth the expense. I was thinking of keeping it as a spare, maybe cheaper to look out for a replacement solenoid for it. 

 

Many thanks for all your help. 

[MtB]

One point. Did you count the teeth on the pinions of both starters? On tooth difference and the new one will prolly work but might slowly mash the ring gear on the flywheel, or just mash it’s own teeth off. Or both. 

[rusty69]

2 minutes ago, Mike the Boilerman said:

One point. Did you count the teeth on the pinions of both starters? On tooth difference and the new one will prolly work but might slowly mash the ring gear on the flywheel, or just mash it’s own teeth off. Or both. 

Yes. The only thing i did check before risking the 20 quid punt was counting the 9 teeth on each. 

Edited September 29, 2018 by rusty69

[Sir Nibble]

It's actually not unusual for starters with different numbers of teeth to be interchangeable. The numbers of units with a reduction gear means that sometimes the pinion is offset from the centre and of larger diameter. The range of motor design, 2,3,4 or even 6 brushes, wound field, sometimes with both series and shunt connection, permanent magnets, maybe 4, maybe 6. Reduction gear from simple spur gears to epicyclic often with rubber cush drive. There is massive variety of design. All that within the range of pre-engaged machines without going into axial and co-axial. The cav co-axial range are superb long lived machines but horribly complex.