carb. float chamber questions

[sujitroy]

Please refer to the photo to the left. According to the buckeye triumph web page, this port, where the pencil is pointing to, is called the
Float Chamber Emissions Port. On my Fed. Stag this goes to a carbon canister. Since UK Stags didn't require this stuff, where does this port connect to?

I do see in the part catalog for European models that these are connected, but it doesn't show where.
Sujit

[DJT]

These are connected to the ‘overflow pipes’ which join together and exit beneath the car. The ‘P’ clip is fixed to the front timing chain cover.

8BE8760E-9BB5-4AD0-9B7D-37CFBDF5FB5E.jpeg


You you can make out the two pipes in this photo

DA86DE67-1615-4D5C-A2BB-34FE9A75C3E9.jpeg

[sujitroy]

thanks. why did they use the larger diameter pipe

[DJT]

No idea. I’ve never seen the 154934 adapters. On my Stags the pipes from the overflows to the tee-piece have all been fuel pipe. 1/4” or 5/16”, whichever is a tight fit. Can’t remember which offhand. The pipe that goes down the front of the engine is plastic.

[STypeR]

Sujit,

From your photo you definitely have got an 'emission' type carb and that for the later cars is called an outlet for the "Vent valve connecting pipes" which the earlier cars did not have. I dont think it is incorrect either to describe it as a 'Float chamber emission port' as per the site you mentioned.
These pipes connect together via a 'T' piece and then to the canister in both earlier and later canister types. I have further details if you need them
That is a 1/4" hose you need to use there. I used a 1/4" vacuum hose and not a 1/4" fuel hose I had as it was too stiff. The Rimmers site shows none of the emission detail or carbs, from that which I assume the UK market may never have had.
Depending on what canister you have/are going to use will depend on what 'T' piece/s you need. As I mentioned there were 2 types of cannister. Maybe provide some more detail of what you are doing/have.
There were several emission carb variations. And we in Australia pretty much got them all, that is - no emission, part emission and full emission.
The adapters mentioned above are for the larger diameter pipes which are 1/2". For our emission cars/carbs these pipes are called the "Canister purge pipes". And for these pipes there are 2 'T' pieces for the later emission cars and for the 'mid' emission cars 2 'T' pieces as well as an 'X' piece. The early emission cars had just the one 'X' piece.
Confused?

[sujitroy]

Hello STypeR.
I'm working on a few things in parallel.
1) I'm trying to figure out if my '71 Stags emissions system was changed. At some point in time, the carbs were changed to a set from a '73. I've been trying to figure out if the carbon canister was changed as well to match. But I'm seeing more material and showing that 3 hole canister was stock. The parts book show some early Stags with two 2 hole canisters. My configuration is not shown.

There's also this issue of a restrictor in the piping from engine breather. I see it in some configurations, but I don't have the restrictor.



2) I'm rebuilding a set of UK carbs from a '76. This will go on a second Fed. '71 Stag I'm working on. The carbon canister was missing, but I was able to source a 2 hole canister.

On the three hole canister, one port goes to the "Float chamber emission port", one to the petrol tank and one to the engine breather, If I use the 2 hole canister and the carbs from the '76. then the Float chamber emission port wont go any where. In this case, I may hook it up similar to what Dave's Stag has. Ideally I should look for a 3 port canister so this can vent into the canister,

Sujit

[STypeR]

Sujit, They made that many carb variations over the years it can get confusing.
Problem can be solved which canister/canisters to use once you know which emission carbs you have.
The earlier canister had 2 holes and the later had 3, as you realise. The early emission cars needed just one 2 hole canister as I think they had no Float chamber emission port/Vent valve on these carbs.
The next stage emission carb which had the Float chamber emission port/Vent valve meant they needed TWO of the 2 hole canisters before they thought of a better idea (and saving some hose and an extra canister) and brought out just the one 3 hole canister.
Someone could probably update if they had the two 2 hole canister set up to the later slightly tidier looking 3 hole single canister if you did not want all the piping in the engine bay.
This 3 hole canister was on many of the Jaguars/other BL products from the same period. They are not cheap to buy at around 100 pounds used each but with the 3 holes at least you only need just the one canister. You will need the plastic 'T' pieces to configure the later breathing arrangement as well as the earlier arrangement. These 'T' pieces are the same as used on the Rovers as well and have a Rover part number also if you are looking for originality, but not too hard to find many generic plastic 'T' pieces that will suit. I think they are 1/2" ends.
Another probably cheaper option would be to buy a generic or say a GM or Ford 3 hole canister used from the same period but you may need some hose adapters as the 3 holes on that canister may not be of the same diameter as the Triumph set up, but that would work.
So as you mentioned you have at least one 2 hole canister and I assume both your cars have the vent valve carbs which you are going to use so you will need another 2 hole canister with 2 'T' pieces and one 'X' style piece. In other words for both cars you will need a total of FOUR 2 hole canisters, OR just get TWO 3 hole canisters.
I have attached a Leyland Australia emission notes update as we got most of the emission cars. The only restrictor I can see is in the 'Canister to Fuel Tank pipe' and I will upload a photo of this that fits in line on the 1/4" hose to the tank. I am not sure what restrictors were in place on the earlier 2 hole canister/s set up.

Cheers

John

[STypeR]

Sujit,

Probably plenty of these available in Australia. Looks like it is made out of brass. No part number or details in the official Triumph manuals that I can find. May be something in the Jaguar manuals of the same period.
I noticed on the canister picture I posted above the 'T' for 'Tank' outlet pipe on the 3 hole canister is on the RH side of the lid. It is a photo for the same part but for a Jaguar XJS I believe. The Stag had it on the LH side of the lid on the RH drive vehicles. I dont know how many of the later sanctions LH drive Stags had the full emission but easy to find out with a quick search. Yours is LH drive so check if these had the lid in reverse on the 3 hole canister.
John

[sujitroy]

Hello John the 3rd photo of the canister in your earlier post was used on Fed '73 model year Stags. The photo with the two top holes looks similar to the one I sourced from a junk yard off an MG I think. With regard to the photo of the restrictor, where did that go?

Sujit

[STypeR]

I just noticed on your first post Sujit that the photo on the right shows an earlier type canister with 3 holes/outlets. The PC does not show this earlier type of canister to have 3 holes but its hardly a surprise there as not everything that went on was shown in the PC. However the ROM does show on page 17.15.00 and 17.15.01 that this earlier smaller type canister did at some point come out with 3 outlets.
So what you found in this car was a correct factory issue at some stage and it looks like this 71' car has had it retrofitted. Since you have this 3 outlet canister, its therefore a match for the emission carb with the float chamber emission port. So you can use this for one car and wont need two times 2 outlet canisters.
I would say you are right in that your original 71' set up was changed as the PC shows the c 71' emission carbs set up only having the Crankcase breather/canister Purge and not the float chamber emission port/vent valve, which came out on the later emission carbs.
If you want to use the other 2 outlet canister you have for carbs with the float chamber emission port means you will need 2 of these canisters. Or ditch this and just find a 3 outlet canister - either earlier or later type.
'Circa 76' carb' could describe a few different emission Stromberg carbs as some of them had one of the emission ports on the bottom. Do the c 76' carbs look like the c 73' carbs? If they do the same set up on each car.
The restictor is in the 1/4" hose that goes from the canister to the fuel tank.

[sujitroy]

Hello John,

I'll take another deeper look this weekend.

Sujit