2500M hand brake light stays on
Discussion
Morning John,
There two systems to the brake warning light..handbrake warning light (2 different systems on the M, the first one, that has a sprung loaded unit attached to the lever which works by adjusting the length of the switch on the chassis mounting AND the second one, that is a mini switch within the lever itself) BUT ALSO the light comes on with 2 other systems TOO early cars have a PWDA valve (read up on how to centralise these) which has a shuttle inside and brings the light on THEN the later cars have a fluid level low within the cap.
Over the years I have removed ALL the PDWA systems from ALL mine and customer cars as I have found them to jam and fail, (this is a long story) causing unbalanced braking in emergency situations! swapping for the later master cylinder (and fluid level warning only).
Adrian@
There two systems to the brake warning light..handbrake warning light (2 different systems on the M, the first one, that has a sprung loaded unit attached to the lever which works by adjusting the length of the switch on the chassis mounting AND the second one, that is a mini switch within the lever itself) BUT ALSO the light comes on with 2 other systems TOO early cars have a PWDA valve (read up on how to centralise these) which has a shuttle inside and brings the light on THEN the later cars have a fluid level low within the cap.
Over the years I have removed ALL the PDWA systems from ALL mine and customer cars as I have found them to jam and fail, (this is a long story) causing unbalanced braking in emergency situations! swapping for the later master cylinder (and fluid level warning only).
Adrian@
Before you rebuild the braking system take a wire off the switch i'n the transmission tunnel. If the light goes out you have 2 options, either leave the wire off and drive the car till you can replace the switch or sell it. If you need a light to tell you you,ve left the handbrake on you may be driving the wrong car
Thanks for the replies, gents.
I'll review my owners manual again for what conditions illuminate the light to make sure it's not something besides the handbrake switch, then if still lit disconnect the switch at the tranny and see what happens.
Adrian, I assume my '77 M, #3668TM, would be considered a later car, correct?
I'll review my owners manual again for what conditions illuminate the light to make sure it's not something besides the handbrake switch, then if still lit disconnect the switch at the tranny and see what happens.
Adrian, I assume my '77 M, #3668TM, would be considered a later car, correct?
Hi John,
No, not late ...I would expect PWDA and sprung hand brake switch on that car ....these are earth out systems, so as Steve says disconnect (the PWDA is a plug so unplug) and this will get the light off, but if it is the PWDA then something more than disconnection of the warning light is called for! it has not shuttled across for no reason and loss of pressure (a leak) at a wheel has caused it to move (that OR have you replaced the fluid and not centralised it).
Adrian@
I MUST hate these thing as even I get the acronym wrong PDWA....
No, not late ...I would expect PWDA and sprung hand brake switch on that car ....these are earth out systems, so as Steve says disconnect (the PWDA is a plug so unplug) and this will get the light off, but if it is the PWDA then something more than disconnection of the warning light is called for! it has not shuttled across for no reason and loss of pressure (a leak) at a wheel has caused it to move (that OR have you replaced the fluid and not centralised it).
Adrian@
I MUST hate these thing as even I get the acronym wrong PDWA....
Edited by Adrian@ on Tuesday 12th July 06:27
Sorry John, I MUST hate these thing as even I get the acronym wrong!! (I have edited it on my previous post) Pressure Differential Warning Activator, this EITHER gets sited next to the steering rack OR on very early cars on the earth tag on the chassis tube above the gearbox I would define all cars with upright radiators as late cars...so, late is 79-81 and 72-77 as early cars. (when you see a lot of TVR's M versions do not EVER get to evolve on like the the Taimar and S)
Adrian@
Adrian@
PWDA................Personally Would Disagree Adrian. Not sure I would class everything prior to 1979-1981 cars as early given they didn,t really "make" any "M" series cars after 1979, although a few were registered. Thats like saying everything with Cortina rear lights is early and everything else is late.
The differences between all "M" series cars is nothing like as complicated as you often make out. Apart from the obvious differences in engine size, coupes, hatchbacks or convertibles most of the differences are evolutionary or detail changes. They ALL have fundamentally the same body, chassis, and that includes the Turbos, front and rear suspension, brakes, glass and general configuration.
I suspect many people must be put off buying an "M" series by some of your postings as too complicated to own. PDWA........ People Definately Would Avoid.
Personally if I had to categorise early and late I would say early had Triumph differentials and later had Salisbury but even that is really irrelevant.
They made almost the same number of cars every year of "M" series production, give or take 1 a day on average apart from 1975 when the factory burnt down which indicates evolution rather than revolution in the development from first to last. Only my opinion. sTeVeR@
The differences between all "M" series cars is nothing like as complicated as you often make out. Apart from the obvious differences in engine size, coupes, hatchbacks or convertibles most of the differences are evolutionary or detail changes. They ALL have fundamentally the same body, chassis, and that includes the Turbos, front and rear suspension, brakes, glass and general configuration.
I suspect many people must be put off buying an "M" series by some of your postings as too complicated to own. PDWA........ People Definately Would Avoid.
Personally if I had to categorise early and late I would say early had Triumph differentials and later had Salisbury but even that is really irrelevant.
They made almost the same number of cars every year of "M" series production, give or take 1 a day on average apart from 1975 when the factory burnt down which indicates evolution rather than revolution in the development from first to last. Only my opinion. sTeVeR@
Edited by thegamekeeper on Tuesday 12th July 08:24
thegamekeeper said:
PWDA................Personally Would Disagree Adrian. Not sure I would class everything prior to 1979-1981 cars as early given they didn,t really "make" any "M" series cars after 1979, although a few were registered. Thats like saying everything with Cortina rear lights is early and everything else is late.
The differences between all "M" series cars is nothing like as complicated as you often make out. Apart from the obvious differences in engine size, coupes, hatchbacks or convertibles most of the differences are evolutionary or detail changes. They ALL have fundamentally the same body, chassis, and that includes the Turbos, front and rear suspension, brakes, glass and general configuration.
I suspect many people must be put off buying an "M" series by some of your postings as too complicated to own. PDWA........ People Definately Would Avoid.
Personally if I had to categorise early and late I would say early had Triumph differentials and later had Salisbury but even that is really irrelevant.
They made almost the same number of cars every year of "M" series production, give or take 1 a day on average apart from 1975 when the factory burnt down which indicates evolution rather than revolution in the development from first to last. Only my opinion. sTeVeR@
The differences between all "M" series cars is nothing like as complicated as you often make out. Apart from the obvious differences in engine size, coupes, hatchbacks or convertibles most of the differences are evolutionary or detail changes. They ALL have fundamentally the same body, chassis, and that includes the Turbos, front and rear suspension, brakes, glass and general configuration.
I suspect many people must be put off buying an "M" series by some of your postings as too complicated to own. PDWA........ People Definately Would Avoid.
Personally if I had to categorise early and late I would say early had Triumph differentials and later had Salisbury but even that is really irrelevant.
They made almost the same number of cars every year of "M" series production, give or take 1 a day on average apart from 1975 when the factory burnt down which indicates evolution rather than revolution in the development from first to last. Only my opinion. sTeVeR@
Edited by thegamekeeper on Tuesday 12th July 08:24
Steve,
I would consider the change in the distance between the main engine bay chassis top rails a major change. I suspect the front top wishbones are different from one version to another, and as such, a potential pitfall for the home restorer, were they to not use caution, and/or post here.
B.
Since my car is a '77, the final year of the 2500M, I assumed it would be considered a "later" car, but since the 1600 and 3000 M cars continued on until '79 I guess that puts me more in the middle.
With the commission # of 3668TM and a build date of June 1976, does that indicate anything major in terms of mechanical characteristics? Does that tell you what diff it has (or how do I tell by looking)? Any other noteworthy updates my car would have or not have?
Thanks again.
With the commission # of 3668TM and a build date of June 1976, does that indicate anything major in terms of mechanical characteristics? Does that tell you what diff it has (or how do I tell by looking)? Any other noteworthy updates my car would have or not have?
Thanks again.
John,
I presume TR6 diff, there is a lots of things that the factory evolved to be better and a good few things that the car would benefit from having done (one being the alloy rack kit mentioned earlier, as this stops the rack from moving, where the Triumph system of mounting the rack uses a spreader tool to force the rack mounts apart, the factory forced a U shaped piece of rubber in to add compression) poly front lower suspension bushes to stop the eyelets from migrating along the bush and damaging the chassis (along with stopping the car from loosing castor under suspension compression) There are several version of the cooling system (you need to have the very last version). HUGE advances have been made in brake materials and tyres. Fuel lines will not be up to taking the current fuels (IMHO change them)...
Adrian@
I presume TR6 diff, there is a lots of things that the factory evolved to be better and a good few things that the car would benefit from having done (one being the alloy rack kit mentioned earlier, as this stops the rack from moving, where the Triumph system of mounting the rack uses a spreader tool to force the rack mounts apart, the factory forced a U shaped piece of rubber in to add compression) poly front lower suspension bushes to stop the eyelets from migrating along the bush and damaging the chassis (along with stopping the car from loosing castor under suspension compression) There are several version of the cooling system (you need to have the very last version). HUGE advances have been made in brake materials and tyres. Fuel lines will not be up to taking the current fuels (IMHO change them)...
Adrian@
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