1970 Corvette brake lights come on and won't go off

Hi there,
After a period of storage I am getting my 350 Hp. stingray ready for the UK test. I notice that the brakes - although functioning OK when
I push the pedal I have to pull it up a bit to get the brake lights at the back to go off. Do you think this is the brake return spring, - where is it, or the switch that turns the lights on, where is that? I could fail the test because of this simple (?) thing!
Another thing, I have gone back to the old coil ignition to get back the use of the rev counter and to make the car a bit more original but I don't know which plugs to use. With the HEI it has been running OK on NGK R BPR6FS but I rememer having a lot of problems with the plugs last time I used the original ignition. I have various plugs in a box. Champion RJ11Y, AC R46TSX and a number of AC 42XLS. Which plugs are most suitable out of these or which would be the preferred one if I have to purchase new?
Regards and thanks, George.
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Are you sure you have a 350 HP or just a 350 CID? Check the engine number suffix for a Cxx hp indicator for the correct HP rating depending on the transmission type. Not an issue, just a point of information.
Standard plug was an R44 (T) (TS) with a .035 gap used in both the 300 and the 350 HP. Nothing shows up in the 46 heat range but does have some use for the 43 range. Bosh HR10AC, Autolite 146, Accel 0566, Champion RV12C, Motorcraft AR8-6, NGK BR5FS, and Denso T16R-U are listed as stock plugs. NGK is the only one I've had an issue with all the others except Accel I've used with Autolite being my choice.
As far as the brake return spring goes you could stand to clean and lubricate the pivot points just above the pedal and steering column and add maybe a second spring inside the original. The switch could also be removed, disassembled, cleaned, and some dry lubricant put on the plunger. The old plunger needs to be smoothed out to return to no contact position easily. The original switch has a die cast body that will get some corrosion in the barrel that restricts movement of the plunger. They are a very cheap switch but also durable so cleaning will work as well as replacement.
Good Luck.........
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Very many thanks Dad, just what I need. The problem is as much my advancing years as the car, I am afraid. I am not so good at laying upside down on the floor with my legs in the air, (luckily it is convertible) to see what is happening under the dash. I am a Grandad!
The VIN is 194670S404768. I think the reason I had so much trouble with the coil ignition, previously was because I failed to ground the distributor, and relied on the clamp to do this. I just could not get a decent spark, although it worked ok when I hooked it all up on the bench. You live and learn. One last thing. The rev counter cable has a permanent S bend in it from years of standing in this position, Shall I accommodated this by moving the distributor round - say one plug position or try and straighten the cable sheath?
Regards, George.
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Snip

Yes, it was hard for me to accept moving one position around the cap but it did take the pinch out of the cable. Wanted to keep it all stock but the shielding hides that little transgression. Previous owner used the right angle adapter and stripped the gears out of the distributor.
On the '70 the vin doesn't indicate HP, engine number on the block does. Your build was very late, last serial number in '70 was 17316, 4910 of them were 350 HP.
Good thought posted by Blue C5, none of my collector cars have power brakes, could be an issue there that I'm not aware of.
Being a grandpa my self I just take a cell phone with me so I can call someone to come unlock my joints and get me out. It's one of the reasons I have a lift, it is so much easier to have it at a reasonable working height and not have to wad myself up to work on the dash. Plus I feel much safer not being under a car on a jack/jack stands.
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Are you talking about the vacuum assist? There is no powrer assist of any other sort. The pedal did not return fully even when the engine was not running. I may have cured it myself as when I did get under the dash with a light I found a cable and connector not going anywhere hanging down. I tucked it out of the way but it might have got between the pedal arm and the steering column. After a lot of pumping up and down it may have just "got better".
I did take a note of the engine number once apon a time. I think it is : 70S404768 VO 209 CTD Does that make sense? What does it all mean?
I have now got it re-assembled with the stock coil etc. It does not run badly with the old plugs NGK R BPR6SF at least that is the one in the No. 1 hole. I took it out to find the compression stroke. I timed it to be about 8 deg. advanced at tickover with the vac. disconnected. The dist. weights definitely advance it to about 20 when I revved it and it went out of sight when I put the vac tube on. When it was warm it was a bit lumpy on tickover but this is probably a Rochester issue. I shall have a look at my carb book for this.
One funny thing. I did the timing with the air cleaner off. When it was warm and ticking over pretty smoothly I put the air cleaner base on the carb while it was running and it suddenly lost revs and stopped. It was quite repeatable. There was nothing touching the carb linkages and this is before I put the filter or top on. I was amazed on how this could happen and finally came to the conclusion that the airflow from the radiator fan was being interrupted by the base of the filter and was somehow changing the mixture. Very strange.
The rev counter works but needs to be done up pretty tight otherwise the inner cable does not engage.
Regards George.
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<Are you talking about the vacuum assist? There is no powrer assist of <any other sort. The pedal did not return fully even when the engine <was not running. I may have cured it myself as when I did get under <the dash with a light I found a cable and connector not going anywhere <hanging down. I tucked it out of the way but it might have got between <the pedal arm and the steering column. After a lot of pumping up and <down it may have just "got better".
Great to hear.
<I did take a note of the engine number once apon a time. I think it <is : 70S404768 VO 209 CTD Does that make sense? What does it all <mean?
That tells you it is the original block and the CTD means it is the 300 HP 350 CID. I miss stated the build date and should have said late '69.
Plug you're using is more like the cooler R43T and will work unless you're regularly banging it down the Queen's carriageway.
<I have now got it re-assembled with the stock coil etc. It does not <run badly with the old plugs NGK R BPR6SF at least that is the one <in the No. 1 hole.
Snip
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.
Thanks again Dad, I am slowly getting there.
I am a little confused by your reference to serial numbers. I have looked up what mine is and I can't see what it has to do with your comment. The serial number is 04768. Where did you get 17316 even if you meant it related to 69? The engine number ends in CTO I think, as this would tie up to Convertible with A/C which it did have before I brought it to UK from the Middle East when I decided it was more trouble than it was worth. There isn't a CTD in the list, as far as I can see and it is easily mistaken. So I was probably mistook.
It has never been restored and things have been fixed as they went wrong. It has a hardtop and only 35500 miles on the clock. My insurer has valued it at not less than 10,000 pounds but as it has a nice registration number, which I would like to retain, I am thinking of trying to sell it abroad, instead of here in the UK. The pound has gone down against nearly every other currency, thanks to the antics of Gordon Brown etc. Would there be a demand for this car in the US?
I would be very happy to hear what you think. I can hardly get in and out with the hood down, thanks to my arthritis.
Thanks a lot George.
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I am a little confused by your reference to serial numbers. I have looked up what mine is and I can't see what it has to do with your comment. The serial number is 04768. Where did you get 17316 even if you meant it related to 69?
Your serial number places the build in late '69. The number 17316 was the last serial number issued in '70. In other words they built 17316 1970 Corvettes.
The engine number ends in CTO I think, as this would tie up to Convertible with A/C which it did have before I brought it to UK from the Middle East when I decided it was more trouble than it was worth. There isn't a CTD in the list, as far as I can see and it is easily mistaken. So I was probably mistook.
CTO only applies to a 350 HP 350 CID with A/C and a manual transmission. You have never stated what transmission it has and I replied before you said it had A/C.
It has never been restored and things have been fixed as they went wrong. It has a hardtop and only 35500 miles on the clock. My insurer has valued it at not less than 10,000 pounds but as it has a nice registration number, which I would like to retain, I am thinking of trying to sell it abroad, instead of here in the UK. The pound has gone down against nearly every other currency, thanks to the antics of Gordon Brown etc. Would there be a demand for this car in the US?
People are alway buying Corvettes and a buyer could be found. Your shipping cost could kill the deal at todays prices.
I would be very happy to hear what you think. I can hardly get in and out with the hood down, thanks to my arthritis.
Thanks a lot George.
I see that you had a flasher problem, did you get it resolved?
Sorry for the late reply but was out of the country on vacation.
--
Dad
05 C6 Silver/Red 6spd Z51
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Since the pedal is being held down, could it not be a bad booster?
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