Please help...carb doesn't fit on manifold!

[boatbuilder]

Hi,

I have a single port 1600 engine on a bus. I have a 1300 manifold. I have a 34 PICT Bocar carb.

The carb won't bolt onto the manifold because the stud spacing is different. Do I really need to get a 1600 manifold, or is it ok to get an adapter plate to make them fit together? Or maybe get a 30 PICT carb?

I bought the 1300 manifold second hand, spent 5 hours cleaning out the heat risers, stripping and painting it, fitted it to the engine, put all the tinware back on again, and now the flippin carb doesn't fit. It would kill me to have to take it all off again and start from scratch with a 1600 manifold. Please tell me what I should do! :shock: :?

 

[VWAIRCOOLED]

Is the inlet manifold hole smaller as well to match the size 30 carb? If so you won't get the same power as fitting the 1600 manifold.

 

[boatbuilder]

Not sure, I'll try to measure it accurately in a few mins...

 

[boatbuilder]

The manifold is 32mm right where the carb joins on, and if I stick the calipers down as far as I can into the manifold, it goes down to 30.2mm

 

[boatbuilder]

A thought has just come into my head.....Is there even such a thing as a single-port manifold to fit a 34PICT carb?

 

[Guest]

A thought has just come into my head.....Is there even such a thing as a single-port manifold to fit a 34ict carb?

Could be correct, surely a 1300 is 31 pict?

 

[boatbuilder]

Well, I've been researching it for a couple of hours now and I am now pretty sure that theres no such thing as a single port manifold suitable for a 34 PICT carb.

I'm gonna see if I can get a H30/31 or a 31 PICT/3. They seem to be the two choices for new single port carbs, they are ok up to 1600 and they will fit right onto my sp manifold. You can even use em on 1600 twin ports with an adapter apparently!

Interesting quote from vw-resource.com.......

Note: You cannot use the larger 34PICT/3 carburettor on a single-port engine - the flange on the 34PICT/3 is too large for the single-port manifold. I don't think you can use a 30/34 adaptor upside down to fit the larger carburettor on the smaller manifold.

 

[VWAIRCOOLED]

That is probably the case.I think the 34 pict 3 carb only came about to fit the twinport engines.You could probably find a way to fit it,but probably the 31 pict3 would be the easiest choice.Try and get the german one if you can.What carb did you have before all this swapping about?

 

[boatbuilder]

I had twin Weber 34ICTs before the swapping about and I had a lot of trouble with them, probably because they were never set up right and I didn't have the patience or know-how to do it.

I got my problem finally sorted yesterday. I got a new Solex/Brosol H30/31 PICT 3 carb and it fitted fine. There was an adapter plate on it for a larger manifold, so I just took it off and then the carb fitted fine. I know these Brosol carbs have a bad reputation and I have noticed while driving around today that the idle rpms seems to go up and down eratically..I suspect the carb return spring is far far too weak.

 

[pete nice]

A 34 carb is only for a 1600 twinport. Single port engines run the 30/31.

Some brand new bocar carbs have a fault on the spindle & leak air causing irratic idle. Spay some brake cleaner or wd40 on the spindle at idle & listen for a change in speed.

Weber ICT's should run .55 idle jets, they are usually jetted wrong unless they come from Eurocarb in Reading. (They re-jet them).

Air leaks are the main source of moody idle problems as are blocked idle jets...

 

[BJ1]

Don't confuse Brosol 30/31 carbs, which are very well made, with Bocar! Bocar are not carbs at all - just modified fishing weights :lol:

I've used Brosol H30/31s for years on 1500 and 1600SP engines - never had a problem with them. Best solution IMO

 

[boatbuilder]

Thanks for that, I think that I was indeed mixing them up with Bocar carbs!