Engine Starting

[howardclark]

I have an 80hp Ford engine with an 80ah dedicated engine battery which can be supplemented with my domestic battery if necessary (usually on v cold winter mornings only)
When i turn the ignition I always get a click from the solenoid on the starter, but quite often that is all. From cold it usually starts first time, but from warm it can take several goes before the starter motor turns over. The battery is fully charged and when it does turn over the starter motor speed is good.
I don't understand this. What is my problem and how can I improve the situation. The battery cables are heavy duty and all connections appear to be clean and sound

Hope you can advise

Howard Clark

 

[pvb]

When i turn the ignition I always get a click from the solenoid on the starter, but quite often that is all. From cold it usually starts first time, but from warm it can take several goes before the starter motor turns over.

The solenoid on pre-engaged starters performs the dual role of moving the starter pinion into mesh with the ring gear, and connecting the power to the starter motor. The contacts which connect the power wear over time, and give the symptoms you've described. You may be able to clean/renovate/replace the contacts in your solenoid, otherwise a replacement solenoid is called for.

Impressive avatar too!

 

[NickRobinson]

A quick bodge test-

Hold the key on 'start' after the solitary click. (Or ask a helper if too far...)

Tap the body of the starter with a small hammer/bar... (Watch your dangly bits)

If it's a lazy solenoid it'll begin to crank at full chat.

Sometimes just cleaning the solenoid and iron core with a solvent (eg petrol, elf 'n safety etc)...., and leaving dry, no lube, can be a permanent cure.

Odd it's better cold than hot though..

Nick

 

[VicMallows]

Agree solenoid contacts is most likely cause. Another possibility though is the motor brushes are worn and sometimes the motor stops with one just failing to make contact. The vibration from a few goes on the solenoid (or a whack with a mallet) can be enough for the brush to just make contact.

 

[howardclark]

thanks - i'll give it a try next weekend

 

[pappaecho]

You should also check your battery connections for corrosion and likewise the EARTH, or negative from battery back to engine. Often this can be the reason, and went on for months on mother inlaws car, so no change there then.

 

[vyv_cox]

I agree the pvb solution, I have done this several times on old VWs, which have a similar starter motor. By removing the solenoid you can usually get to the brass contacts, which become pitted over time.

There is another cause, which is the braided wire that delivers current from the contacts into the motor. This is quite exposed and can corrode badly. I have managed to bodge a solder repair but it really needs to be replaced by a specialist.