There are 2 pipes coming off the side of the carb which at the moment are not attached to anything, I believe they are breather/overflow pipes, so do they need to be atached to anything or should I run them out of the engine bay?

Cheers

[Edited on 29/10/15 by JamesyCottony]

May help if you say wat engine and carb you have
Jacko

But its raining ouside ............Fine....

The two pipes shown in the middle here:




number 2&3 on this page:



http://www.minimania.com/SU_CARBS___Connection__HIF_type

twin SU carbs/1


http://www.britishcarforum.com/bcf/showthread.php?45618-HIF44-Carb-Questons-need-some-information

[Edited on 29/10/15 by jacko]

quote:

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Originally posted by jacko

twin SU carbs/1


http://www.britishcarforum.com/bcf/showthread.php?45618-HIF44-Carb-Questons-need-some-information

[Edited on 29/10/15 by jacko]

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This might help:


hif44

Basically, they're fine as they are.

you need a pipe of the float vent going down under the car if fuel comes out this pipe you don't want it spraying on the exhaust / manifold

quote:

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Originally posted by jacko
you need a pipe of the float vent going down under the car if fuel comes out this pipe you don't want it spraying on the exhaust / manifold

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hif44

Number 7 on this picture

you also appear to have a vacuum advance take off, 'A' in pic below. (also 9, not shown on the other pics)


Description

quote:

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Originally posted by gremlin1234
you also appear to have a vacuum advance take off, 'A' in pic below. (also 9, not shown on the other pics)


Description

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SU carbs as im sure you know.

Large diameter is breather and connects to engine .

Smaller is float chamber vent, if the needle valve fails to close, as can happen if left standing for a while, petrol will wee out of it. Connect pipe to it and route it so that the outlet is away from any heat or electrical sources to avoid fire. THIS IS V IMPORTANT for safety reasons.

As someone pointed out, there is vacuuuuuuuuum take off to distributor advance. Connect it or if distributor does not have vacuuuum advance, block it off.

quote:

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Originally posted by 02GF74
SU carbs as im sure you know.

Large diameter is breather and connects to engine .

Smaller is float chamber vent, if the needle valve fails to close, as can happen if left standing for a while, petrol will wee out of it. Connect pipe to it and route it so that the outlet is away from any heat or electrical sources to avoid fire. THIS IS V IMPORTANT for safety reasons.

As someone pointed out, there is vacuuuuuuuuum take off to distributor advance. Connect it or if distributor does not have vacuuuum advance, block it off.

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quote:

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Originally posted by JamesyCottony

quote:

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Originally posted by 02GF74
SU carbs as im sure you know.

Large diameter is breather and connects to engine .

Smaller is float chamber vent, if the needle valve fails to close, as can happen if left standing for a while, petrol will wee out of it. Connect pipe to it and route it so that the outlet is away from any heat or electrical sources to avoid fire. THIS IS V IMPORTANT for safety reasons.

As someone pointed out, there is vacuuuuuuuuum take off to distributor advance. Connect it or if distributor does not have vacuuuum advance, block it off.

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Thanks for the replies everyone .

With the breather would it connect to a small little flying saucer shape thing by the alternator?

With the distributor advance vacuum pipe should there be a small pipe in the distributer that this would connect to?

Thanks again

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Breather is to burn off blow-by gas , usually it connects to the top part of the engine e.g. rocker cover. Combustion gas gets past rings and pressurises crankcase, on ohv engine it get into top via holes for push rods.

Good explanation why you want to do this is here.

http://www.bobistheoilguy.com/what-is-blow-by/

quote:

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Originally posted by jacko

quote:

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Originally posted by JamesyCottony

quote:

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Originally posted by 02GF74
SU carbs as im sure you know.

Large diameter is breather and connects to engine .

Smaller is float chamber vent, if the needle valve fails to close, as can happen if left standing for a while, petrol will wee out of it. Connect pipe to it and route it so that the outlet is away from any heat or electrical sources to avoid fire. THIS IS V IMPORTANT for safety reasons.

As someone pointed out, there is vacuuuuuuuuum take off to distributor advance. Connect it or if distributor does not have vacuuuum advance, block it off.

---

Thanks for the replies everyone .

With the breather would it connect to a small little flying saucer shape thing by the alternator?

With the distributor advance vacuum pipe should there be a small pipe in the distributer that this would connect to?

Thanks again

---

On some cars the dizzy has a small pipe for the vacuum if you don't have this on your dizzy just block the one on the carb off
the breather pipe would normally go to the air filter box but in your case feed it under the car if you are going for a iva it will have to go to the air filter box
jacko

[Edited on 1/4/16 by jacko]

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quote:

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Originally posted by 02GF74
Breather is to burn off blow-by gas , usually it connects to the top part of the engine e.g. rocker cover. Combustion gas gets past rings and pressurises crankcase, on ohv engine it get into top via holes for push rods.

Good explanation why you want to do this is here.

http://www.bobistheoilguy.com/what-is-blow-by/

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Dont think you said what engine you have but i deduce a series. It may have crankcase breather, see here.

http://appraisalnewsonline.typepad.com/our_mini/2012/12/classic-mini-engine-bay-crankcase-breather.html

Re distributor vacuum advance connector
See here.
http://www.pertronix.com/prod/new/details.aspx?id=122
Disc on left hand side is it, the small pipe is connected to the carb. You need special hose, it is firm plastic so does not collapse under vacuum and has two rubber connectors at each end.

[Edited on 2/4/16 by 02GF74]

quote:

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Originally posted by 02GF74
Dont think you said what engine you have but i deduce a series. It may have crankcase breather, see here.

http://appraisalnewsonline.typepad.com/our_mini/2012/12/classic-mini-engine-bay-crankcase-breather.html

Re distributor vacuum advance connector
See here.
http://www.pertronix.com/prod/new/details.aspx?id=122
Disc on left hand side is it, the small pipe is connected to the carb. You need special hose, it is firm plastic so does not collapse under vacuum and has two rubber connectors at each end.

[Edited on 2/4/16 by 02GF74]

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Would this be the crankcase breather?

IMAGE

quote:

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With the distributer pipe can I just use non collapsible rubber?

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quote:

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Originally posted by gremlin1234

quote:

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With the distributer pipe can I just use non collapsible rubber?

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this should fit, from minispares. should be easily available elsewhere too

http://minispares.com/product/Classic/Engine/37H4229M.aspx

[Edited on 2/4/16 by gremlin1234]

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quote:

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Originally posted by JamesyCottony
Would this be the crankcase breather?

IMAGE

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quote:

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Originally posted by 02GF74

quote:

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Originally posted by JamesyCottony
Would this be the crankcase breather?

IMAGE

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You need someone who knoes bout a series engines minis etc to answer that.

It is a breather but judging how clean it is, it could be new or inlet. For example on rover v8, there is inlet to crank case, air drawn in and two outlets on both rocker covers.

If what you show is outlet, it soon will be clogged and dripping with oil. You would be better off connecting hose and feed into oil catch tank, simple and cheap is old beer can. Search for oil catch tank here to see solutions.

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the large pipe goes direct into the inlet behind the butterfly, you'll get a very lean mixture if you dont connect it or blank it off. I have both of mine connected to the rocker box take off via a fume/ flame trap, never caused me any trouble apart from routine cleaning of trap. My friend races a Sprint he has a short piece of tube and a bolt to block it off, we tried to link the two together but it upset the balance of the carbs, so we ditched that brain wave !

quote:

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Originally posted by sprintB+
the large pipe goes direct into the inlet behind the butterfly, you'll get a very lean mixture if you dont connect it or blank it off. I have both of mine connected to the rocker box take off via a fume/ flame trap, never caused me any trouble apart from routine cleaning of trap. My friend races a Sprint he has a short piece of tube and a bolt to block it off, we tried to link the two together but it upset the balance of the carbs, so we ditched that brain wave !

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For the pipe that connects the crankcase breather to the carb does it need to have a really high temperature resistance, or can I use radiator hose?