Bad starter- electrical problem

[stigproducts]

Hi, I would appreciate some pointers with my V6 Essex.
It is always very reluctant to start when cold. it turns and turns and turns and then, if the battery has enough juice, will eventually fire.
I have a sloped driveway and if the battery dies it will 9 times out of 10 fire if I run it down the drive and bump start it. So obviously the spark and fuel are there- but why not when it is on the starter?? Perhaps the starter it taking so much power the spark is weakened? All the electrical bits have been replaced, over the last few years, but it has pretty much always done this.

I am thinking a bad connection somewhere; any hints where to start?

Thanks guys

[steve_D]

Disclaimer: My answer is not based on any knowledge of this motor.

Many Fords use a balast wire in the ignition which is basically a resistor which reduces the voltage to the coil. The coil is low voltage (i think 9V) and this is how it normally runs.
When you start, the starter is pulling all the power and not leaving much for the ignition so a wire runs from the starter solenoid to the ignition coil which over volts the ignition. This wire may be broken. Sometimes in this situation the engine will just catch as you release the starter.

Someone will now pipe up that this system is not used on the Essex so all this typing will have been in vain but hay, I tried.

Steve

[rustybin]

Engine Earth Strap OK?

When it turns, is it labouring or spinning fairly freely?

[stigproducts]

It spins pretty well. The earth strap was replaced last year.
Yes it does have a ballast resistor setup. I will check this out tonight. Any wire going between the starter solonoid and the coil has to go closely past the exhaust manifold so would be a good candidate for damage.
I am assuming that if I run a multimeter between the + or the coil and a earth, I should get 12v when the starter is turing and 9v once the engine starts. If i don't (always 9v) then the 12 v bypass is at fault. Please correct me if I am wrong.

Any other suggestions gratfully received, so I have a few possibilities before I start to get my hands dirty!

[steve_D]

While cranking you may not get 12V but should get better than 9V.
If similar to Cortina wiring then ignition wire (Black) goes into the Ballast wire. Other end of ballast has 2 Black/yellow wires. One goes to coil positive the other goes to pin 16 on starter. So when cranking the 12V should come from the starter up to the end of the ballast and join with the 9V coming out of the ballast and go to the coil.

Steve

[stigproducts]

Thanks for the suggestions. Cranking gave a meagre 3/4/5 amps at the coil. and when I ran a wire direct from the battery + to the coil it fired up straight away.
Lo and behold, hanging below the starter is an unconnected female bullet. Problem now is that the manifold has to come off to get at it, and to achieve that the heater has to come out.....etc! The manifold needed to come off anyway as it rubs against the chassis and needs to be modified.

One other thing I noticed was that the business end of the ballast resistor has 3 out going wires. One of these goes directly to a weird cylinder thing bolted to the back of the engine- what does this do?

[steve_D]

stigproducts said:

.....One other thing I noticed was that the business end of the ballast resistor has 3 out going wires. One of these goes directly to a weird cylinder thing bolted to the back of the engine- what does this do?

Don't ask me, I only solve one problem at a time and besides I've already said I don't know the engine.

If getting to the starter is such a pain just run a wire back into the dash and wire to a pushswitch which you hold down just whilst starting. Fix the problem when it's a bit warmer out.

Steve

[liszt]

You'd better get this fixed for Le Mans otherwise we goin' gumball stylee and the motor is not gonna get stopped until we hit Expo!

[eliot]

steve_D said:

If getting to the starter is such a pain just run a wire back into the dash and wire to a pushswitch which you hold down just whilst starting. Fix the problem when it's a bit warmer out. Steve

Range Rovers have a similar system. I used a relay that's engergised on cranking to deliver 12v directly to the coil.

[stigproducts]

liszt said:

You'd better get this fixed for Le Mans otherwise we goin' gumball stylee and the motor is not gonna get stopped until we hit Expo!

You assume nothing else will break!

All back together now, and it's made sod all difference, so looks like it is the auto electrician for me :-(

I have rigged in a switch from tbe battery + to the coil + as suggested to give it a wee boost on cold mornings- sticking plaster!!

>> Edited by stigproducts on Thursday 17th February 15:10

[dern]

Measure the voltage drop across the earth strap and the the +ve lead to the starter when you crank it. My westfield dropped 1v across the +ve lead which meant that it would start when warm but not when cold. Replacing the offending lead sorted it out.

Mark