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Greetings to all, this is my first atttempt at the forum and I would welcome your help and advice in getting a much mistreated Dart back on the road here in Spain.

First, now Ive got my carbs back (they were getting muddy on a Kanguru for a while..) can somebody please confirm the connections for the carb breather pipes. Am i right in connecting the breathers from the 2 smaller spigots together in pairs and the breathers from the larger spigots (from the float chambers) to a Tee piece and then to the labyrinth breather.

Secondly, what would be a starting setting for the pilot screw (mine had one screwed up hard and the other at 2.75 turns out....).

Lastly - what is the correct chain running standard sprockets - I believe the correct size to be 520 O ring with 114 links including the link - is this right?

Many thanks, geoff

Hi Geoff,

There should be 2 small breathers and one large per carb. The small breathers I am pretty sure are the ones which link to the float bowls, the large being downstream for balancing and blowby recirc.

Anyway, the 4 small ones as standard go to the 4 small holes in the shroud above the air filter intake. The large ones tee together and then join to the one way valve. Most people end up just venting the 4 small breathers to atmosphere and linking the 2 carbs directly together with a balance pipe, junking the t piece, one way valve and collector box and instead venting rocker boxes to atmosphere and the crankcase to atmosphere via a labyrinth as per the older bikes.

mixture screw i normally start at 1.5 turns out. obviously both carbs will require a different amount once you've balanced them but anything less than 1/3 out indicates too small a pilot jet. obviously it's important to make sure the jets, float height (and weight!) are correct before starting the process of balancing, and make sure the cables are roughly balanced to start with too.

520 114 link including split link sounds right to me. I don't bother with o ring chains on my dart, instead opting for the best quality non o ring chain i can get, but i realise this is personal preference. a 520 o ring chain will fit the dart.

Let us know how you get on,
Tom

morini_tom wrote: Most people end up just venting the 4 small breathers to atmosphere and linking the 2 carbs directly together with a balance pipe, junking the t piece, one way valve and collector box and instead venting rocker boxes to atmosphere and the crankcase to atmosphere via a labyrinth as per the older bikes.

On other Morinis I blank off the balance pipe, but the Dart throttle cable setup is pretty sloppy, so it probably benefits from the pipe.

mixture screw i normally start at 1.5 turns out. obviously both carbs will require a different amount once you've balanced them but anything less than 1/3 out indicates too small a pilot jet.

You mean too big an idle jet, since the mixture screw controls fuel, not air. If the mixture screw has little effect (and the passageways aren't blocked) it can indicate that the slide is too far open and you're onto the progression circuit. Idle speed it controlled by both the idle stops (assuming the throttle cable actually has some slack in it!) and ignition timing. Too retarded and you have to jack the slides open beyond the idle circuit.

EVguru wrote:You mean too big an idle jet

You are quite right Paul, what I meant to say (and did before my phone lost internet causing me to hurriedly rewrite the message) was less than 1/3 out indicates you need to fit a smaller pilot jet

Ah Haaa, so thats what those 4 Little holes in the air filter housing are for!!!
Many thanks to Paul and Tom for their help - I shall re plumb it as suggested and see what happens.
All the best, geoff