stag starter motor

[barryandangela1980]

Hi
I have a 73 stag that i have owned for nearly 12 years that i do not use as much as i would like to (less than 200 miles this year).It had a new starter motor fitted and a top end rebuild last summer.I went out in it a few nights ago with the wife (bad mistake) whilst out after it had ran fine for about fifteen minutes it stalled restarted stalled again.When I tried to re start it the starter motor would not disengage with the engine running nor could i stop either by removing the keys.The car then caught fire and the inside of the car started to fill with smoke on a junction in the middle of a very busy dual carraigeway.Fortunately I had a fire extinghiusher and was able to pull one of the battery leads off and put out the fire.It was then recovered to home.The source of the fire looks as thought it was the new starter as the wires from it were badly burnt.I have had someone look at it for me today.The starter had a wired in wing mounted relay with badly burnt exposed wires this was removed and a new starter fitted there was no other obvious sign of damage to the wiring.The car then started and ran for about fifteen minutes then stopped.We had terrible trouble getting it started initially it ran as though it had a misfire then ran smoothly then stopped.At this point we became aware that the coil and all the low tension wires were hot thenwires had began to smoke.I am a little baffled by
1/ why did the starter motor not jam when i left home.
2/ why did the car stall then restart itself.
3/ why did the starter not disengage and burn out the wiring.
4/ why did it have a ? starter relay fitted i checked my Haynes manual and could not find one listed.
6/ why did it run with the new starter without a relay.
7/ why did it stop after 15 minutes then run rough then over heat the coil and low tension wires.
Has anyone suffered or know of this happening before.On of my concerns is that perhaps the fire may have cone more damage to the harness than first thought.
thanks
barry

[Staggard]

The stag solonoide pull a lot of power thus shortens the life of the contacts in the ignition switch, so a lot of owners have fitted a relay in between the ign switch and the solonoide ( I have) if the relay or the solonide jamed in this would run 12volt to the 6volt coil this would explain the coil getting hot and maybe breaking down and stopping the engine. All the time the starters engaged it will run power to coil and the engine will continue to run even with the ign off and the keys out. This is a good reason to fit a battery isolater. Hope this helps Graham

[barryandangela1980]

hi graham
thanks for the response it does make sense i will let my mechanic know.i bet the weather is a lot better there than here guess what its raining again.
regards
barry

[barryandangela1980]

hi graham
thanks for the response it does make sense i will let my mechanic know.i bet the weather is a lot better there than here guess what its raining again.
regards
barry

[dasadrew]

Sorry to hear of your woes, but top marks for having a fire extinguisher on board! It could have gone very nasty after your car had caught fire. I wonder how many people drive around without one.....

[jleyton]

Bloody hell Barry - that was pretty dramatic. Glad it turned out ok for you and your wife.

As Graham has said, fitting a relay in the starter motor circuit not unusual and, I reckon, is a pretty good idea.

Starter motors jamming in the engaged position is not that unusual and, once the engine's running, can often go unnoticed. Sod's law decrees that there is no rhyme nor reason as to when it will jam, or when it won't

However, with, effectively, the engine powering the starter motor, at far higher revs than it is ever designed to run at, it's usually not too long before the starter burns out.

You may know that there is a feed from the starter motor to the coil that provides the coil with 12v whilst cranking, rather than the 6v it gets normally - to give an extra boost to the coil just during starting. It would seem that, as your starter motor was still running, the coil was still getting this 12v which would definitely overheat the coil after a fairly short time. Possibly the coil has been damaged as well ?

Good luck and glad to hear it was not even worse.

Cheers

Julian

[V Mad]

An alternative explanation is that the ignition/starter switch may have failed and stuck in the 'start' position. It would be easy to check that out.

[barryandangela1980]

stag starter motor

An alternative explanation is that the ignition/starter switch may have failed and stuck in the 'start' position. It would be easy to check that out.

The mechanic from the local Stag specialist looked at the car on Thursday.He fitted a new starter motor the wires from the starter to the relay were badly burned so he removed them as well as the relay.He connected the original wires to the starter motor these were burnt but not as much as the relay wires the car then started.It ran for fifteen minutes then cut out.It did restart but ran badly as if it was not firing on all cylinders.At this point the coil had become very hot as had the wires leading from it.He was unsure what to do next so disconnected the battery and left.I have since spoken to the owner of the garage who thinks the coil may have burnt out at the time of the fire.The plan now is for the car to be taken to the garage on Monday by trailer.They will then do a thorough check of the electrics and fit a new coil before attempting to restart the engine.The owner of the garage and his mechanic have been very good about it. As the car has done less than 200 miles and less than twelve months since they fit a recon starter motor and did a top end engine rebuild (£2400) they seem agreeable to repairing the car at there expense.
Regards
Barry