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cu with jk's webber conversion kit driving us mad

Posted: 18 Jan 2007, 13:53
by colinMSC
totaly give up :x we have been driving an x reg bus for acouple of years now .
we fitted a jk webber kit just after getting it. after striping the carb and setting it up properly[ which it wasn't] finaly got the choke working ok!!.
we are still left with a bus which is undrivable from cold. we know its somthing to do with carb freezing/poor mix when cold , if you leave her running for 10 min before setting off in the morning she is fine, but god help you if you try to start and go because it just won't . coughs splutters and even dides , we are not dum dum's but it's got us beat short of taking it off and smashing it to peices and puting the original carbs back on is there any thing we can do to stop/ cure this problem :?: :?:
ps its not out of tune in any way :)

Posted: 18 Jan 2007, 14:05
by Mocki
you need to talk to "grumpy midget" off here, he sorted his same set up iirc....

Posted: 18 Jan 2007, 22:20
by jason k
contact www.raceshack.co.uk
they will put you right,
the stock jets are way too small and they will jet it and set it up properly on the dyno for you.
money well spent.
they set mine ( twin dual delloertos ) and germmans (twin icts) beautifully.

Posted: 18 Jan 2007, 22:29
by Simon Baxter
That carb is a step backwards from the standard ones.
You've gone from 2x 26mm venturis down to one 26 for most of the rev range and then a bit more there after.
They aren't designed for type 4 motors, and eurocarb (importers of Dellorto and Weber) won't sell that kit for a type 4 engine.
That said, once it on and running (poorly I must add) then they will need jetting on the rolling road to get them to do anything like what they are meant to.
A pair of original solex's with the mod to the throttle spindles are a fine carb. If you want to go faster and get more economy then fit a pair of Weber IDF 36's or 40's, or some delorto DRLA 36's or 40's.

The weather has been a bit mild for carb icing, but it may be worth ducting some warm air from the exhaust to the air filter for the winter months as a see you through.

Posted: 19 Jan 2007, 01:01
by Fritz
Colin, the Grumpy Midget had similar problems some time ago but managed to persevere with the problem till a suitable cure was found.

In fact the problem was similar in many ways to the icing problem bettles used to suffer from,,,,,,,,the fix was a pre fabricated pre heat pipe linked to the carb to eliminate the overcooling of atomised gasses travelling along the extended inlet manifold of the single carb set up.


Regards

Fritz,,,,,,,

PS, same as what yer man above is saying really,,,,,,, :D

Posted: 19 Jan 2007, 12:09
by colinMSC
thanks all , as she runs realy well in warm wether and fuel economy is more important to us than performance, i think we will try rigging some sort of pre heat pipe up, as fritz said the fault is similar to what happens to beetles.

Posted: 19 Jan 2007, 17:19
by toomanytoys
If you can duct a bit of warn air off the heat exchanger that will help, but a session on a rolling road with someone that is good with carbs would help too.