What on earth is wrong...
Discussion
...with my car! So, long story short. Starting issues, clicking from the solenoid, but doesn't start. Starts when bump started etc. Replaced both battery terminals, then replaced them again with better quality ones, still doesn't make a difference. Battery was new in August, Westco, shows 12.5v when engine is off, when I have got it started, shows 13.1 whilst running. Changed the starter motor for an (apparently) working one, then tested my old starter motor by clamping it in a workmate, and wiring it up to my battery, and it spun in the bench, so that was probably fine?
Hit the starter motor several times with a wrench, not a stuck solenoid.. checked all connectors I can see / feel under the bonnet, everything is connected.. It actually started ONCE yesterday, after my brother left his optimate motorbike charger on the battery, but it didn't start again.
ANY ideas? I'm thinking it could still be the battery, but his Optimate charger (pretty old one) didn't seem to work properly, as it was never showing the battery condition (it either says good or bad) and was always showing as charging.
I know MX5 parts have a charger, but I don't fancy forking out £60 to find out it's not that, and I'm left with a charger I have no use for.. Anyone in the Berkshire area got one I could borrow?
Cheers.
Hit the starter motor several times with a wrench, not a stuck solenoid.. checked all connectors I can see / feel under the bonnet, everything is connected.. It actually started ONCE yesterday, after my brother left his optimate motorbike charger on the battery, but it didn't start again.
ANY ideas? I'm thinking it could still be the battery, but his Optimate charger (pretty old one) didn't seem to work properly, as it was never showing the battery condition (it either says good or bad) and was always showing as charging.
I know MX5 parts have a charger, but I don't fancy forking out £60 to find out it's not that, and I'm left with a charger I have no use for.. Anyone in the Berkshire area got one I could borrow?
Cheers.
I remember your recent post about this. Sorry to hear you're having a bit of a nightmare with it.
Here are a few thoughts.
Although you say it's showing 12.5v with the engine off, how long after switch off is that? Does the charge decay after, say, an hour or two to less than 12V?
12.5 would be enough of a charge if the battery was near the engine and only attached by chort cables but with the battery in the boot the resistance might be very high along its run. Maybe there's an area of high resistance or damage between front and back.
I would be expecting more like 14V if the alternator was charging properly. This could either be down to a slightly loose belt or the same resistance that I suggested earlier.
I hope you get to the bottom of this.
Here are a few thoughts.
Although you say it's showing 12.5v with the engine off, how long after switch off is that? Does the charge decay after, say, an hour or two to less than 12V?
12.5 would be enough of a charge if the battery was near the engine and only attached by chort cables but with the battery in the boot the resistance might be very high along its run. Maybe there's an area of high resistance or damage between front and back.
I would be expecting more like 14V if the alternator was charging properly. This could either be down to a slightly loose belt or the same resistance that I suggested earlier.
I hope you get to the bottom of this.
13.1 is a bit on the low side for a running engine.
put your volt meter between the battery neg terminal and a a good clean part of the body,anything above 0.2v indicates a dodgy earth,put the lights on or get someone to turn the key and see if the voltage rises,if it does,dodgy earth.
put your volt meter between the battery neg terminal and a a good clean part of the body,anything above 0.2v indicates a dodgy earth,put the lights on or get someone to turn the key and see if the voltage rises,if it does,dodgy earth.
gforceg said:
I remember your recent post about this. Sorry to hear you're having a bit of a nightmare with it.
Here are a few thoughts.
Although you say it's showing 12.5v with the engine off, how long after switch off is that? Does the charge decay after, say, an hour or two to less than 12V?
12.5 would be enough of a charge if the battery was near the engine and only attached by chort cables but with the battery in the boot the resistance might be very high along its run. Maybe there's an area of high resistance or damage between front and back.
I would be expecting more like 14V if the alternator was charging properly. This could either be down to a slightly loose belt or the same resistance that I suggested earlier.
I hope you get to the bottom of this.
12.5v was with the engine being off for over an hour easily, as it wouldn't start again after the first time.. it decayed slightly, but it dropped every time I turned the key to try and start it, so I put it down to that.. I haven't seen it drop below 12v, but I will get it checked tonight and see how much it is holding now.Here are a few thoughts.
Although you say it's showing 12.5v with the engine off, how long after switch off is that? Does the charge decay after, say, an hour or two to less than 12V?
12.5 would be enough of a charge if the battery was near the engine and only attached by chort cables but with the battery in the boot the resistance might be very high along its run. Maybe there's an area of high resistance or damage between front and back.
I would be expecting more like 14V if the alternator was charging properly. This could either be down to a slightly loose belt or the same resistance that I suggested earlier.
I hope you get to the bottom of this.
I guess the cable could be damaged between front and back, how to check this though?
Perhaps I should check the alternator belt then, as the alternator may not be charging the car.. as a couple of weekends ago I ran it for over an hour and a half, and it should of charged the battery fine, but it wouldn't start on its own 24 hours later...
stevensdrs said:
Earth strap corroded?
Sorry, where is the earth strap?There should be a short earth strap going from the neg terminal of the battery attached to the body. Take it off and clean up where it connects. Even better go to your local motor factors and get a new earth strap it wont be much as these can deteriorate.
I hate problems like this I hope it is an easy fix for you.
I hate problems like this I hope it is an easy fix for you.
Spoke to MX5 parts, and they reckon the battery is dead. And have advised charging it for 3-5 days! I charged it for 12 hours on an Optimate, and it was red hot after 12 hours..
..Anyone else stuck a Westco on for so long? I'm paranoid it's going to melt and set fire to my lounge whilst I'm asleep...
..Anyone else stuck a Westco on for so long? I'm paranoid it's going to melt and set fire to my lounge whilst I'm asleep...
My Westco is on charge on an Optimate pretty much all the time as it sits in the garage most of the time and I keep the charger plugged in to stop it dying. It doesn't get even slightly warm, let alone hot! It sounds to me like you either have a fault in the Westco or in the Optimate.
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