Bendix drive from starter motor

[guymcc]

Afternoon folks

I'm having trouble with the starter motor on the car. Turning the ignition all i can hear is the starter spinning and not engaging any sort of drive? I've pull out the starter and using jump leads from a good battery on another car, it spins up fine. If looking at the starter from end on, from the square drive end/front, its spinning anti-clockwise. Is this correct? For the life of me i can't work out how the drive then engages? The bendix will move freely by hand, and it will move towards the stater body when power is applied but is also then moves away.

When on the car does the bendix sit engaged or disengaged, i'm guessing dis engaged? It just seems weird that is spinning up ok but clearly not engaging?

The engine turns over by hand i should add.

Hopefully someone will be able to help

[oliver90owner]

Teeth on either bendix or starter ring damaged or worn.

Insufficient voltage at connection. Solenoid, or battery/earth connections with high resistance. Possibly a cell has failed in your battery?

Starter motor 'lazy' and in need of overhaul.

Bendix either dirty or worn out.

Does the starter engage if jumped with some good jump leads when fitted to the car. I mean heavy duty, not 'halfords specials'

That should do for a start (pardon the pun!).

[mogbob]

What general state is the Bendix end in ? Dirty or clean.
In a clean working state , you should be able to move the Bendix assembly along it's thread , towards the Starter motor casing. It should move freely and without sticking. There is a small spring in the assembly providing resistance. When you let go , it should snap / spring back to the end of the shaft.
General checks ...are the Bendix teeth in good condition, i.e the bulk of the metal is still there and not badly burred over.
Buffer spring ( the big thick one ) is still in one piece , no obvious breaks / fractures in it.
The carbon bushes are in a good state ( i.e plenty of meat left on them )
the main power supply terminal ..secure and clean ?
Is the battery on your car in good condition.
Action the pinion teeth on the starter ( at rest in the car ) is thrown into mesh with the teeth on the flywheel , when you operate the starter. The flywheel turns , the car starts and the engine rotates. This engine action "overtakes " the speed of the starter motor and the pinion is thrown " out of mesh " with the flywheel. The return spring snaps it back to it's resting position , ready for next time it's called upon.
The pinion end can be cleaned with Meths and a brush over a jam jar / foil dish , etc but do NOT oil it . It will stick again very quickly if you do and you'll have to take the starter motor out again.

You can get the bits to repair a starter motor but you will need a specific Bendix compressor spring to safely remove the C Clip.
DON'T be tempted to try Heath Robinson methods !! The buffer spring is very powerful and flying metal will injure you very efficiently.
If the motor has seen some service and there are multiple issues to correct , most people opt for a new or reconditioned Starter motor.

For perfect working order you need :- a fully charged battery , good clean electrical connections, a working starter Solenoid , a working
ignition switch , correct starter motor in working condition, a good earth connection ( both the engine and gearbox earth straps are present ? clean and secure. ).
Come back at us for any clarification / further comments.
Bob

[guymcc]

Thanks guys for the replies!

She lives! I figured out what the starter does to achieve the meshing and therefore i put it back on to the car. It's a very new starter motor and in excellent condition. What i did the second time was to put power from my other car (a B4 audi 80 btw) and connected the lead directly to the starter motor. Clearly this gave it enough juice to kick the bendix into the correct posiiton and the car turned over. After a quick check and rub of the spark plugs and to make sure fuel was getting pumped, i got her to fire in to life!

So yeh, starter all good, no worn teeth on either that or the flywheel. I'll get the battery replaced with a new one. What do people go for? I've got a fairly small one, so perhaps something better would aid successful starts going forward.

Thanks for all the pointers!! I've not been on here for ages, but always nice to get quick and really helpful replies, much appreciated gents!

[firedrake1942]

Go for the best one you can afford. The tiny ones which all the books say are okay for the minor haven't got the guts especially if you are still running a dynamo. I would recommend at least a 95AH heavy duty. The battery compartment will take a larger one as batteries have shrunk over the years.

[oliver90owner]

I wouldn't be recommending as high as 95Ah for this application. Small diesels don't fit them that big. 75Ah is more than adequate. But do go for one with a decent cca. Some batteries might have the capacity to store the energy but not to delivery it quickly enough or for very long.

One important aspect with lead acid batteries is to maintain full charge (never allow it to be stored for extended periods while partly discharged, even).