8 replies to this topic

[Tommyboy12]

Hey guys.
I believe my carb tune is massively out as the car was running lean for its MOT and gave up on me on thursday. Today im going to have a crack at resetting the carb to at least get it running again. However, while I can find information on the base setting I cant find any that agrees with each other! So far ive come across one saying bridge the jet internally with the top of the carb off then turn 1/2 turn in, some say two turns in from flush with the body of the carb, another says three turns from flush!
Anyone have any idea which is right? I dont need exact tuning I just need to get the car running enough to drive to a garage for a tune up with a gas analyser.

[minilester]

the reason your geting different opinions is that they are prob. all running different needles...

in all honesty try all of them wen it fires into life let it run for a min or 3 then let it cool and see if the spark plugs are all black and if they are then its too rich.. go for a little trial and error. running rich it should bogg down a little but running really lean start to kill my engine.. so start backwards! start with 3 turns from flush and trail it from there

[Tommyboy12]

Well its a BDP needle if thats any help? I had it running momentarily at 3 turns but it died with minor throttle and hasnt started since.

[Ethel]

If it dies when you touch the throttle it's likely too lean. Set it so the jet is 1 or 2mm below the bridge. Get it running at fast idle (there's an arrow on the choke lever to line up with the fast idle screw). Use the lifting pin to lift the piston, the revs should drop a little but recover. If the revs increase instead, it's too rich and if it really struggles or stalls it's too lean. Once you've got it good enough to run go for a drive to warm the engine then adjust the same again.

[Tommyboy12]

Thanks for that. Ive given up for tonight to let the battery charge and the starter motor recover! Tomorrow I shall give it another try. I know its the carb its just getting it started!

[Tommyboy12]

No luck again today. So I took the carb off. Stripped it, checked it and cleaned it. The seals and everything looks ok, there are no splits or chunks missing, but is it worth replacing them? By the looks of the screws im the first to take it apart and the seals must be getting on for 25 years old now.

[Tommyboy12]

Double post....

Edited by Tommyboy12, 25 July 2011 - 09:23 PM.

[Brams96]

I'd replace the seals anyway if they are that old, the rubber seals may look ok but probably wont be as supple as they should be to seal properly, a gasket seal kit is only about £8.50 or the full rebuild kit with spindle, butterfly, jet etc is about £45. There is a Mini Mag article about carb set ups by Keith Calver floating about the web which is a good read, I can't seem to find the link though.

Edited by Brams96, 25 July 2011 - 09:12 PM.

[Tommyboy12]

Might as well buy a seal kit then. The jet and spindles look in good condition and there are no noticeable leaks.