Why our Starter Motors die regularly
Discussion
Hi there,
Have just got a new starter motor from a specialist for the S.
He explained three reasons why these motors seem to die with such regularity which I thought I'd share with you.
1) The biggest reason. It's damned hot. A lot worse than for the Granada. It's often hot enough infact to melt solder. Eventually the solder has been thru enough hot / cold cycles to turn into a "dry" joint which is intermittent. This is why sometimes they start from cold - but not from hot.
The solution to this is to give your starter motor some sort of heat shield. Some sort of tinfoil / asbestos amalgam no doubt. Anyone have ideas on how to build one of these ?
2) Sometimes the voltage drop thru the ignition is such that only around 9V is reaching the armature. This isn't good for that either. However, it's easily solved by using it as input to a relay to switch a full twelve volt feed from the battery. Should probably put a fuse on that feed (haven't done that yet).
3) Not enough charge from the battery means turns over slower than it should - over time this can knacker the windings so that it always turns over slowly.
So, fitting a heat shield and a relay should help most people.
Hope this helps,
WG
>> Edited by WonkyGibbon on Wednesday 3rd August 16:20
Have just got a new starter motor from a specialist for the S.
He explained three reasons why these motors seem to die with such regularity which I thought I'd share with you.
1) The biggest reason. It's damned hot. A lot worse than for the Granada. It's often hot enough infact to melt solder. Eventually the solder has been thru enough hot / cold cycles to turn into a "dry" joint which is intermittent. This is why sometimes they start from cold - but not from hot.
The solution to this is to give your starter motor some sort of heat shield. Some sort of tinfoil / asbestos amalgam no doubt. Anyone have ideas on how to build one of these ?
2) Sometimes the voltage drop thru the ignition is such that only around 9V is reaching the armature. This isn't good for that either. However, it's easily solved by using it as input to a relay to switch a full twelve volt feed from the battery. Should probably put a fuse on that feed (haven't done that yet).
3) Not enough charge from the battery means turns over slower than it should - over time this can knacker the windings so that it always turns over slowly.
So, fitting a heat shield and a relay should help most people.
Hope this helps,
WG
>> Edited by WonkyGibbon on Wednesday 3rd August 16:20
Hi Wonky
the Griff and Chim kids have been adding the relay to cure the "hot start" but its the solenoid feed that sees the reduced voltage and must be the same for you. 9v at the armature would not turn it over and is not handled at all by any part of the ignition switch or wiring,its direct from the battery. So dont mean to "poke my nose in" but it is the solenoid wiring at fault, that turns on the direct supply from the battery. Hope not to offend !
the Griff and Chim kids have been adding the relay to cure the "hot start" but its the solenoid feed that sees the reduced voltage and must be the same for you. 9v at the armature would not turn it over and is not handled at all by any part of the ignition switch or wiring,its direct from the battery. So dont mean to "poke my nose in" but it is the solenoid wiring at fault, that turns on the direct supply from the battery. Hope not to offend !
david beer said:
Hi Wonky
the Griff and Chim kids have been adding the relay to cure the "hot start" but its the solenoid feed that sees the reduced voltage and must be the same for you. 9v at the armature would not turn it over and is not handled at all by any part of the ignition switch or wiring,its direct from the battery. So dont mean to "poke my nose in" but it is the solenoid wiring at fault, that turns on the direct supply from the battery. Hope not to offend !
Indeed, I think that's what I've got. So what was the solenoid feed from the ignition is now used to switch the direct 12V supply from the battery which then runs on to the solenoid. Hope I've got that right. But all advice always gratefully reveived.
Talking of which ...
Anyone got any thoughts on how to do heat shielding for the starter and solenoid ? The Bible recommends it but doesn't give any clue as to how. I was thinking I could make a gasket to cut down the heat transmitted from the bell housing but from the rest of the engine ?
The other thing I noticed was that my battery has the higher crank current rating of 630 Amps used for the V8S rather than the 590 you'd expect for the S3. Has anyone seen problems with this higher current capacity damaging the starter ?
Thanks,
WG
Hmm... 17 years on the original starter motor, maybe I should be worried???
The starter (and solenoid) are direct connection to the battery and earth via the chassis. There has to be an issue there if you only see 9v when cranking (or the battery is nazz).
For heatshield there is a suitable one fitted to the Land Rover Discovery. Its semi-foldable material.
The starter (and solenoid) are direct connection to the battery and earth via the chassis. There has to be an issue there if you only see 9v when cranking (or the battery is nazz).
For heatshield there is a suitable one fitted to the Land Rover Discovery. Its semi-foldable material.
Starter Motor back on - boy is that an improvement !!
Trying to locate Heat Shield from either Leven or Rally Design ...
One other nasty problem, this time with the main power feed from the battery to the starter (the big unfused high current one). The last inch of this is basically a ring terminal that attaches to the starter. This comes to within 1/4 to 1/8" of the chassis at one point (the bit of the chassis beneath the engine mount). I've got as much clearance as I can out of the arrangement and bolted it v tight to the terminal. But it still gives me the willies ! It's not too much to believe that it could short the battery given time.
Does anyone know if standard insulation tape would withstand the temperatures you get there - or is there some more pro stuff I could use ?
Thanks,
WG
Trying to locate Heat Shield from either Leven or Rally Design ...
One other nasty problem, this time with the main power feed from the battery to the starter (the big unfused high current one). The last inch of this is basically a ring terminal that attaches to the starter. This comes to within 1/4 to 1/8" of the chassis at one point (the bit of the chassis beneath the engine mount). I've got as much clearance as I can out of the arrangement and bolted it v tight to the terminal. But it still gives me the willies ! It's not too much to believe that it could short the battery given time.
Does anyone know if standard insulation tape would withstand the temperatures you get there - or is there some more pro stuff I could use ?
Thanks,
WG
WonkyGibbon said:
Does anyone know if standard insulation tape would withstand the temperatures you get there - or is there some more pro stuff I could use ?
Standard tape is a definite nono.
There exists several high temperature insulations. Best type would be a kind of braided tube like fibreglass cloth. No idea of the name.
Use heatshrink tube as insulation over the cable and then the fibre braid tube over that.
Le TVR said:
Standard tape is a definite nono.
There exists several high temperature insulations. Best type would be a kind of braided tube like fibreglass cloth. No idea of the name.
Use heatshrink tube as insulation over the cable and then the fibre braid tube over that.
Thanks mate. I'll go looking for a supplier based on that.
... and that supplier is "Rally Design" www.rallydesign.co.uk/
Very helpful people. Got some sheet heatshield and some cable heatshield all in for about £20.
>> Edited by WonkyGibbon on Friday 5th August 13:33
Gassing Station | S Series | Top of Page | What's New | My Stuff