Starter motor and brake light switch
Discussion
Hi,
Pleased to say the Caterham acquited itself extremely well on its first track day on Friday. At higher speeds it was rather outgunned in a straight line, but that's no big surprise when the aerodynamic inspiration is a brick. I think I'm right in saying the only things that were cornering faster were the other Sevens though. Even the X-Bow seemed to be marginally slower in the twisties.
Anyway...
The downsides were that the 'Caterham click' with the starter motor went from a one-off to a permanent problem and it appears the brake light switch has conked out (I'm told this is another common problem?)
I know this is a whole can of worms, but what's the simplest solution. A Brise (sp) starter motor with a heat shield? Does anyone have a part number or a link for one, and can someone explain what's involved in doing a starter motor change on a 1.6 K-Series?
Secondly, I'm told you can strip and clean the brake light switch? Is this worth doing, and if so, how? Presumably if not (or just as a spare) Caterham could supply a replacement?
Many thanks,
Chris
PS Is it worth getting a workshop manual for the engine, and if so, which one? It's a Minister-built Supersport effectively, running a dry sump system, but presumably things like the ancillaries would be standard Rover?
Pleased to say the Caterham acquited itself extremely well on its first track day on Friday. At higher speeds it was rather outgunned in a straight line, but that's no big surprise when the aerodynamic inspiration is a brick. I think I'm right in saying the only things that were cornering faster were the other Sevens though. Even the X-Bow seemed to be marginally slower in the twisties.
Anyway...
The downsides were that the 'Caterham click' with the starter motor went from a one-off to a permanent problem and it appears the brake light switch has conked out (I'm told this is another common problem?)
I know this is a whole can of worms, but what's the simplest solution. A Brise (sp) starter motor with a heat shield? Does anyone have a part number or a link for one, and can someone explain what's involved in doing a starter motor change on a 1.6 K-Series?
Secondly, I'm told you can strip and clean the brake light switch? Is this worth doing, and if so, how? Presumably if not (or just as a spare) Caterham could supply a replacement?
Many thanks,
Chris
PS Is it worth getting a workshop manual for the engine, and if so, which one? It's a Minister-built Supersport effectively, running a dry sump system, but presumably things like the ancillaries would be standard Rover?
Chris,
If it's any help, the original Rover workshop manual for the K-series engine forms part of the Lotus Elise S1 factory workshop manual, which is usually pretty easy to find as a free download on the web (try searching SELOC or Sands Motor Museum).
If it's any help, the original Rover workshop manual for the K-series engine forms part of the Lotus Elise S1 factory workshop manual, which is usually pretty easy to find as a free download on the web (try searching SELOC or Sands Motor Museum).
I wouldn't bother to fix a broken brakelight switch: https://www.caterhamparts.co.uk/product_info.php?p...
Cheers gents.
Starter motor wise I take it this is the one I want?
https://www.caterhamparts.co.uk/product_info.php?p...
(Well, obviously it'll fit, but is that one recommended and are Caterham cost effective people to buy it from?)
By the way - somebody mentioned rocking the car backwards and forwards in gear as a temporary fix in the previous thread and it does seem to work. It took a few 'rocks' but it persuaded mine to stop clicking and start this afternoon.
Starter motor wise I take it this is the one I want?
https://www.caterhamparts.co.uk/product_info.php?p...
(Well, obviously it'll fit, but is that one recommended and are Caterham cost effective people to buy it from?)
By the way - somebody mentioned rocking the car backwards and forwards in gear as a temporary fix in the previous thread and it does seem to work. It took a few 'rocks' but it persuaded mine to stop clicking and start this afternoon.
Chris, before embarking on buying a new starter, I'd try and establish what is going on. Have a go at identifying the problem before buying relatively expensive parts!
First of all, check the connection to the solenoid on the starter. If the terminal is all loose, then that's a problem and the solenoid can be replaced or repaired.
If the terminal is not loose, wire in a fly lead in parallel and run it up to the battery and secure in the vicinity of the positive terminal UNCONNECTED of course! When you get the click, whip off the bonnet, touch the fly lead to the positive terminal of the batt and see if it starts. If it does it every time, then the "relay trick" will solve your problem.
Regarding the rocking. I know I am at odds to the other poster, but I don't think it's having any effect. It's just that you are re-trying the solenoid and eventually it works.
Re brake lights. Whip the cover off the pedal box and see what's going on. The plate that operates the switch could be bent, or the switch could be loose. There could be a bad earth as well.
Bert
First of all, check the connection to the solenoid on the starter. If the terminal is all loose, then that's a problem and the solenoid can be replaced or repaired.
If the terminal is not loose, wire in a fly lead in parallel and run it up to the battery and secure in the vicinity of the positive terminal UNCONNECTED of course! When you get the click, whip off the bonnet, touch the fly lead to the positive terminal of the batt and see if it starts. If it does it every time, then the "relay trick" will solve your problem.
Regarding the rocking. I know I am at odds to the other poster, but I don't think it's having any effect. It's just that you are re-trying the solenoid and eventually it works.
Re brake lights. Whip the cover off the pedal box and see what's going on. The plate that operates the switch could be bent, or the switch could be loose. There could be a bad earth as well.
Bert
Brake light switch takes all of 2 seconds to dismantle and have a look inside. Remove it from the car and using a fine bladed screwdriver or knife, gently prise the small plate off at the rear. Be careful the spring doesn't get lost! The usual problem is a small build up of crud on the terminals. Give it a quick wipe and snap it together. Should take a minute to do the job...
ge2 said:
What exhaust are you running?
I looked into the Brise starter for my RSA but it wouldn't fit with the 4-1 competition exhaust as the primaries run too close to the engine
Good point. It's a 4-1 but I think it's just the standard one - the car had a 4-2-1 in its competition days that was removed as part of the sale.I looked into the Brise starter for my RSA but it wouldn't fit with the 4-1 competition exhaust as the primaries run too close to the engine
BertBert said:
If the terminal is not loose, wire in a fly lead in parallel and run it up to the battery and secure in the vicinity of the positive terminal UNCONNECTED of course! When you get the click, whip off the bonnet, touch the fly lead to the positive terminal of the batt and see if it starts. If it does it every time, then the "relay trick" will solve your problem.
Hi Bert,I had a quick visual check first time and nothing is obviously loose. With regards to the fly lead can you explain what exactly is happening - does that bypass the relay and just sent the current straight to the starter? Presumably that means the relay is bust but the motor is good and you can just fit a replacement relay? Must admit I don't really know anything about the practicalities of engine electrics and I'm a bit reluctant to start prodding around when we're talking about something that carries the full cranking current!
Chris71 said:
I had a quick visual check first time and nothing is obviously loose. With regards to the fly lead can you explain what exactly is happening - does that bypass the relay and just sent the current straight to the starter? Presumably that means the relay is bust but the motor is good and you can just fit a replacement relay? Must admit I don't really know anything about the practicalities of engine electrics and I'm a bit reluctant to start prodding around when we're talking about something that carries the full cranking current!
hehe, I am talking about the feed to the solenoid, not that fat current feed to the starter.The 12v to the solenoid is generated from a relay in the black box (MFU) under the ECU. When you turn the key (or press the button) to fire the starter, the 12v from the key, fires the relay which switches 12v to the solenoid. Over time this seems to not be "enough" so the solenoid just clicks.
So my diagnostic trick is to take 12v straight from the battery to the solenoid. If that works when you get the click, then the starter is ok, but the feed circuit from the MFU is not enough.
Then the "relay fix" is to wire in an extra relay which is fired from the old solenoid feed and takes 12v straight to the starter from the battery (fused of course).
Probably easier to talk through than describe!
Bert
BertBert said:
Chris71 said:
I had a quick visual check first time and nothing is obviously loose. With regards to the fly lead can you explain what exactly is happening - does that bypass the relay and just sent the current straight to the starter? Presumably that means the relay is bust but the motor is good and you can just fit a replacement relay? Must admit I don't really know anything about the practicalities of engine electrics and I'm a bit reluctant to start prodding around when we're talking about something that carries the full cranking current!
hehe, I am talking about the feed to the solenoid, not that fat current feed to the starter.The 12v to the solenoid is generated from a relay in the black box (MFU) under the ECU. When you turn the key (or press the button) to fire the starter, the 12v from the key, fires the relay which switches 12v to the solenoid. Over time this seems to not be "enough" so the solenoid just clicks.
So my diagnostic trick is to take 12v straight from the battery to the solenoid. If that works when you get the click, then the starter is ok, but the feed circuit from the MFU is not enough.
Then the "relay fix" is to wire in an extra relay which is fired from the old solenoid feed and takes 12v straight to the starter from the battery (fused of course).
Probably easier to talk through than describe!
Bert
It does make sense, because as you may remember the first time this happened we successfully revived it with a jump start (providing a little extra voltage to the solenoid perhaps?)
I'll take a look at the contacts and see if I can work out what's what (I presume this is fairly straightforward, I just can't remember the arrangement off the top of my head).
And, Fergus, if the relay trick fails I'll give you a shout.
Quick update, which maybe someone who knows a bit more about electrics than I do can deduce something from...
The rocking thing does appear to be a red herring in this case at least. Rocked to my hearts content last night and the damn thing still wouldn't start. However, after putting it on a jump start it went first time. Obviously whatever it is just needs a bit more oomph to overcome.
Does that narrow it down at all?
Didn't think to check the battery, but it's fairly recent and no reason to suspect it isn't healthy.
Double checked the starter motor connections and everything is secure.
So is it just a case of running a bit of wire from one of those across to the positive terminal to test the relay theory? What exactly is the problem inside the MFU, would it not be easier to replace the offending part or wiring than wire in a new relay?
Thanks for the help chaps, it is appreciated.
The rocking thing does appear to be a red herring in this case at least. Rocked to my hearts content last night and the damn thing still wouldn't start. However, after putting it on a jump start it went first time. Obviously whatever it is just needs a bit more oomph to overcome.
Does that narrow it down at all?
Didn't think to check the battery, but it's fairly recent and no reason to suspect it isn't healthy.
Double checked the starter motor connections and everything is secure.
So is it just a case of running a bit of wire from one of those across to the positive terminal to test the relay theory? What exactly is the problem inside the MFU, would it not be easier to replace the offending part or wiring than wire in a new relay?
Thanks for the help chaps, it is appreciated.
Good pic Chris.
The brown wire is the activation feed to the solenoid. when I did it, I put a piggy-back spade connecter on the end of a similar guage wire to run as a fly lead.
The piggy-back connector has a female connector to attach to the solenoid and also a male spade sticking out to re-attach the brown wire. So you don't disturb wiring.
Run the fly lead up to near the battery so you can touch the end onto the positive terminal. If you do that whenever you get the click (and it starts), you know you can fix the problem by adding another relay.
If you want I could make up a suitable lead tomorrow and stick it in the post to you. Or if you wanted to pop over to chez bert in epsom at some point, we could do it then. Or we could go straight to the relay mod. I'm around pretty much all weekend.
Bert
The brown wire is the activation feed to the solenoid. when I did it, I put a piggy-back spade connecter on the end of a similar guage wire to run as a fly lead.
The piggy-back connector has a female connector to attach to the solenoid and also a male spade sticking out to re-attach the brown wire. So you don't disturb wiring.
Run the fly lead up to near the battery so you can touch the end onto the positive terminal. If you do that whenever you get the click (and it starts), you know you can fix the problem by adding another relay.
If you want I could make up a suitable lead tomorrow and stick it in the post to you. Or if you wanted to pop over to chez bert in epsom at some point, we could do it then. Or we could go straight to the relay mod. I'm around pretty much all weekend.
Bert
Hi Burt,
That's tremendously kind of you, but I'm likely to be away at the weekend (may be passing Epsom, but sadly in the daily driver!) May take you up on that at in the near future though, although I could possibly do with getting a crimping tool myself anyway, so might just give you a ring for some guidance!
Chris
Don't want to sound obsequious, but I really am chuffed with what a nice bunch you Caterham lot are. I owe a couple of people favours already, so if anyone needs an extra pair of hands locally (for anything unskilled that is!) do give me a shout.
That's tremendously kind of you, but I'm likely to be away at the weekend (may be passing Epsom, but sadly in the daily driver!) May take you up on that at in the near future though, although I could possibly do with getting a crimping tool myself anyway, so might just give you a ring for some guidance!
Chris
Don't want to sound obsequious, but I really am chuffed with what a nice bunch you Caterham lot are. I owe a couple of people favours already, so if anyone needs an extra pair of hands locally (for anything unskilled that is!) do give me a shout.
Another way of looking at the problem? IME the fundamental cause has been in the starter motor / solenoid. The function of the solenoid is to engage the motor with the starter ring on the flywheel and it does that by physically pushing a gear wheel forward. At the very end of its travel it also makes some fairly hefty contacts to energise the starter motor and we're in business. The click you hear is the solenoid being enegised, what you don't hear is the motor whirring because the solenoid travel has stopped fractionally short of making the contacts.
The cause of the problem I've found (I'm not saying it is the only possible cause) is that the smear of grease that lubricates all these sliding bits not only picks up dust and dirt over time but more critically it gets carbonised by the heat of the exhaust that surrounds it. That then prevents the last smidgeon of travel needed to make the contacts. There is also a heat effect that joins in the party because while the symptoms are slowly deteriorating, leave it to cool off a bit and it will sometimes work again. Presumably expansion is making the stiction a bit worse.
Under these circumstances anything you can do to get just a little extra oomph from the solenoid could be enough and reducing the volts drop by shunting the relay may well do it. Burnt relay contacts may also be the culprit or if not entirely at fault certainly won't help.
About every couple of years or so, when the symptoms return, I've ended up taking the starter / solenoid apart and thoroughly cleaning the old grease and muck out and then applying a very sparing film of grease before rebuilding. Never failed to fix it. Thought I'd be clever on one occasion and re-assembled totally dry so as not to trap dirt and have nothing in there to carbonise. Trouble was there was nothing there to lubricate either
Rocking the car won't help this type of starter because it isn't engaged with the starter ring. What may work in an emergency though is to gently bash (technical term) the side of the starter motor while you are trying to start the car. It might just be enough to get that last bit of travel while the solenoid is energised.
The cause of the problem I've found (I'm not saying it is the only possible cause) is that the smear of grease that lubricates all these sliding bits not only picks up dust and dirt over time but more critically it gets carbonised by the heat of the exhaust that surrounds it. That then prevents the last smidgeon of travel needed to make the contacts. There is also a heat effect that joins in the party because while the symptoms are slowly deteriorating, leave it to cool off a bit and it will sometimes work again. Presumably expansion is making the stiction a bit worse.
Under these circumstances anything you can do to get just a little extra oomph from the solenoid could be enough and reducing the volts drop by shunting the relay may well do it. Burnt relay contacts may also be the culprit or if not entirely at fault certainly won't help.
About every couple of years or so, when the symptoms return, I've ended up taking the starter / solenoid apart and thoroughly cleaning the old grease and muck out and then applying a very sparing film of grease before rebuilding. Never failed to fix it. Thought I'd be clever on one occasion and re-assembled totally dry so as not to trap dirt and have nothing in there to carbonise. Trouble was there was nothing there to lubricate either
Rocking the car won't help this type of starter because it isn't engaged with the starter ring. What may work in an emergency though is to gently bash (technical term) the side of the starter motor while you are trying to start the car. It might just be enough to get that last bit of travel while the solenoid is energised.
I suffered chronic click when I first had my seven.
There's loads on this if you search blatchat but you'll need to get the multimeter out & figure out which of the several issues is causing your click, best description/advice I've seen is this quoted from LH on old Jock 7's
The starter gets too hot and jams
Clean and lube starter gear with dry slide or other non liquid dry lubricant
Solenoid fails to pass sufficient current to turn starter
replace solenoid
12v fails to reach solenoid
check by sending 12v supply on fly lead direct to solenoid
MFRU relay fails to send 12v to solenoid
replace relay with external version
Soldered wire to solenoid in starter has mechanical fracture
resolder wire in starter
Battery gubbed
replace battery
all of the above
sell car to DDtB
There's loads on this if you search blatchat but you'll need to get the multimeter out & figure out which of the several issues is causing your click, best description/advice I've seen is this quoted from LH on old Jock 7's
The starter gets too hot and jams
Clean and lube starter gear with dry slide or other non liquid dry lubricant
Solenoid fails to pass sufficient current to turn starter
replace solenoid
12v fails to reach solenoid
check by sending 12v supply on fly lead direct to solenoid
MFRU relay fails to send 12v to solenoid
replace relay with external version
Soldered wire to solenoid in starter has mechanical fracture
resolder wire in starter
Battery gubbed
replace battery
all of the above
sell car to DDtB
I think that starter is different to mine (perhaps why the rocking thing doesn't help as the previous poster said?) - taking mine out, cleaning it up (and re-greasing it) and replacing the wiring and the relay did help mine for about a year, but again not sure that'll help as it does look different to mine. A heavy hammer and a tap to it also tended to help...
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