Amazon: Brake light switch

[SvenSomerset]

Okay, we have twin SUs, so which way do I turn the idle adjustment screws to raise the RPMs when the choke is full out, to stop the rich mixture fouling the plugs and cause the engine to stall? To the right (clockwise) or to the left (anticlockwise)? I don't wanna make the problem worse! And of course I'll only adjust the fast idle screw on each carb 1/8 of a turn at a time... I take it that the screw labelled '2' on the attached image is the fast idle screw, as it seems to be connected to a cam?

[Derek UK]

Maybe the picture of your brake light switch was taken before you checked it but if not remove the connectors and clean them up with emery paper. Do the tabs on the switch and then clean up the female ones. They should fit tightly. If loose, a very light squeeze with pliers should tighten up the tubes a bit. Take it easy, it's easy to squash them. Doesn't matter which one goes on which tab. Temperature won't affect the switch.
+1 to OF's adjustment. That gives you some extra revs, to about 1k rpm when the choke is about 1/8 to 1/4" out from the dash and the jets are fully back up. You might have to reset the position of the choke wires at the carb ends. Car will chug if over choked but set correctly it won't be over rich but will idle at higher revs. Yes it's cold but 2-3 miles should have the needle in the middle and you can put the choke all of the way in. If you start out from cold and take it for a run without coming to a halt it's easy to forget that it's still out a bit as it will drive OK but may knock a few mpg's off. We've all done it............

[SvenSomerset]

Thanks Derek, think I was editing my last post as you were writing! Can you please confirm the direction that the fast idle screws need turning, in order to raise the RPM, and also that they're the ones labelled '2' on the image I attached to my last post?

[old fart]

If you turn the screw '2' in (i.e. clockwise) until it touches the cam, the back it off a touch, and see what that's like.Regards, Andy.

[Derek UK]

Is that your manifold? It's one of the nasty emissions ones with the secondary butterflies. If working well, no problem but they aren't the best option.
Yes screw #2 is the one to adjust. With the choke fully in there should be a small gap between the screw and the cam. It's a normal screw so clockwise in and anti clock out. When you pull the choke a fraction the screw pushes on the cam and raises the tick over. The cam is shaped to give a proportional increase. As said this first small movement should raise the revs without pulling the jet down so more revs but no enrichment. The gap is a little bit trial and error and you may prefer a slightly higher "fast idle". Set the gap the same on both carbs. Not shown in the pic but adjust the cables so the cam is fully down. Make these adjustments with the engine fully warm and idling normally. i.e. the idle screws, #1 are set correctly.

I see that Andy is following but with much less waffle........

Go for it.

[old fart]

Morning Derek, less waffle because my typing finger gives out after a not many words. Happy New Year folks. Andy.

[Splinelube]

Could anyone post the approximate or better precise time that Volvo changed the Amazon brake like switch configuration. I get the impression that their are two varieties, i.e. early and late. My car is a 66. Thankyou, Russ

[Ron Kwas]

Forum;

I have limited/slow access, so quick answers/comments only:

SL; Brk Lt Sws were changed in the '67 year...I expect chassis dependent...exploded parts diagrams and parts lists on GCP site may tie this to specific chassis numbers. I expect your 66 will have early style...confirm by inspection

SS; You're already getting good advice from other posters, but just observe that Fast Idle Adjust Screw acts upon same shaft as Throttle...this adjustment is fairly touchy, and 1/8th turn will have a significant affect, but don't be afraid to tickle it up a bit...remember to do other carb equally...

Brk Lt Sw is not specifically temp sensitive, but were talking about the electrical action of a (likely carbonized) contact closing under dead slow movement transferred by hydr pressure...how predictable and consistent can you expect that to be...more like totally unpredictable with gentle pressure...that's why they will work with panic-stop pressure and fast application...it cuts through the carbonization...the entire thing is highly "iffy" though (engineering term).

Cheers and Happy New Year from Lake Placid!

[SvenSomerset]

Thanks and HNY to you all, Derek, Ron and Andy!

Originally Posted by Derek UK

Maybe the picture of your brake light switch was taken before you checked it but if not remove the connectors and clean them up with emery paper. Do the tabs on the switch and then clean up the female ones. They should fit tightly. If loose, a very light squeeze with pliers should tighten up the tubes a bit. Take it easy, it's easy to squash them. Doesn't matter which one goes on which tab. Temperature won't affect the switch.

Have plans to do this tomorrow...

Originally Posted by Derek UK

Is that your manifold? It's one of the nasty emissions ones with the secondary butterflies. If working well, no problem but they aren't the best option.

It isn't a pic of Sven's manifold, just one I found on t'internet!

In terms of sorting the fast idle issue, despite your sterling advice, we decided to just pop Sven up to Jim at Weston Garages, as he's been looking after the car since we experienced the 'crud in the lines / carbs' issue back in the spring. As Jim totally sorted that, retuned the SUs and the worked out the distro/timing/condenser problems, he knows Sven intimately so it should be a ten-minute job, and there's ZERO chance I'll mess it up! As I'm a total mechanical newbie, I always first ask the experts (you lot!) for advice, which is always VERY MUCH appreciated, so I understand the cause and solution, then I work out if I feel comfortable doing it or can find someone locally to do the work properly. In this case, I do feel a mite out of my depth (even though it's, in theory, very simple!) so off to Jim we go...

Oh, we also ran into local PV/Amazon tuner/racer Keith Wilson while out and about over the festive season – he seems like a totally sound fella! In other news, Chris (aka Volvo133) has kindly sold me a set of 'type 3' grilles for a very fair price (see photo), to replace the 'type 4' ones which are currently on there. And yesterday I again spotted a petrol blue Amazon with what looked like a vinyl 'slide back' sunroof driving along in Bath! Anyone know who that is? The only other Amazon owner we know hereabouts is Jamie, whose car is just finishing its comprehensive restoration... there's a quite raggy looking, dark blue Combi often parked up over the other side of the river from us, and it appears that it's in use; I've seen a smoke grey Amazon occasionally in the Homebase car park; and then there's the petrol blue one... would love to get together when the weather turns warmer, to swap tips and such, so if anyone knows who the 'smoke grey' and 'petrol blue' owners are, please lemme have their info! Maybe they're on the forum already!

[jimbo1593]

Davy,
Practical classics have had a number of small pieces on crap Chinese parts, to paraphrase, perhaps they would be interested in your brake switch research.

James

Originally Posted by davybl

Our investigations reveal that the switch can be procured for between 15 and 20 British pence per thousand minimum order quantity. The retail price ranges from £4 to £5+ with one extortionate mini trader asking £14+!