carb help please

[messer]

can someone give me some carb knowledge pleeeease........I have a prob with tickover at junctions,roundabouts,etc, but only when its hot,half hour or so driving, I dont know why but I undid the air bypass screw,as I was told this could have a bearing on my prob, I counted out how many turns, tried starting my bus(westy '71 1776cc 110 engel cam) to try tickover,but now it struggles to start(till I messed it started straight up). When it starts it just wont tickover, I had put the ab screw in up to where it was before(or so I thought, I did count) but still having prob. Dont you wish sometimes to leave well alone!I do Can some of you carb experienced guys help this novice, I'm trying to sort it myself but I aint doin a good job! So I would be grateful for your expert advice!! Previous till tonight it ran well till hot, but it also gave me black ssmoke marks on me bumper, running rich eh? Anyway I've blahhed on a bit, over to you guys! hopefully.......................

 

[noddy]

Just turning the air bypass screw out will probably have leaned the mixture off too much and thats why you are having trouble getting it started, too much air and not enough fuel.

You should only set the tick over on a running warm engine, air bypass screw is mainly used to get the tickover between 800 and 900 rpm.

Base setting for the fuel screw is 2.5 to 2.75 turns out from home (don't screw hard into the seat it knackers the end of the screw and the seat, makes setting a real pig in the future).

Then adjust tick over speed with air bypass screw to the 800 to 900 rpm range.

What is your tick over problem you don't describe what is happening when the engine is hot, is it cutting out, going on to very low tick over?

 

[messer]

Hi Noddy,
Thanks for great advice, I' ll give it a go with the screw settings later or tomorrow, cheers!

Yeah, when its hot it just cuts out, stalls at junctions etc ,sometimes it'll start again straight away, but sometimes you have to give it 10/15 mins,(till its cooler) hope this helps, cheers again

oh yeah forgot to say...it's a brand new Bocar 34 pict 3, couldn't get a Solex

 

[steve92]

im a bit of a carb numpty ,but maybe this will help?
http://www.vw-resource.com/34pict3.html#carb" onclick="window.open(this.href);return false;

 

[messer]

yeah , but I'm carb numpty no.1 !
great site Steve, thanks for link and help.
cheers

 

[messer]

Hi, noddy , thanx for your advice, followed it, & wow! ticking over just great, many thanks mate, is good to learn stuff like this also cheers to steve92, great site, in my faves now! cheers guys

 

[noddy]

No problem dude glad to hear your now sorted.

 

[steve92]

nice one!

 

[Bookwus]

Hiya mess,

Take the following for what it might be worth................

It has been my experience that Bocar 34PICT3 are not well put together right out of the box. It's almost as if these things have put together in a mud hut. I now do not bolt any Bocar on right outta the box. I do a little diassemble and clean jets and passages. That helps. But quite honestly I would go for a rebuilt Solex over a new Bocar any day of the week.