Page 1 of 1

Adjusting and Balancing Carbies

Posted: Sat Apr 30, 2005 9:08 am
by BIg StEvE
I have a 3.5lt carbie in my rig at the moment and i want to get it roadworthy! All i have to do to it now is adjust the carbies to get it running smoother and less rich! However i have no clue when it comes to this. I was wondering if there was someone in the north to north/eastern suburbs of Melbourne that would be willing to give me a hand?

I have thought about putting it into the proffesionals but the closest one cant take me for 2-3 weeks! :?

Any help would be greatly appreciated :armsup:

cheers
;)
Steve

Posted: Sat Apr 30, 2005 7:42 pm
by Casey_leonard
Hi Steve
Just in case you cant wait for the dealer or get someone to do it for you.
It requires 2 tools, one to do the mixture and one to do the balance.
The mixture adjusting tool can be purchased from a dealer, the balancing tool you may be able to purchase from your local parts place like Repco.
A peice of garden hose can be used for the balancing if you dont want to fork out for the proper tool.
Once you have the mixture set and the vehicle idling put one end of the hose to your ear and the other just in the entrance to the carby inlet (air filters removed of course).
You can now hear the amount of sucking each carby is doing and by adjusting the idle screws on each carby you can balance them.
i.e. if one carby is sucking harder than the other back off the idle screw and viser verser. Keep going back and forth until they both sound the same and your idle speed is correct.
The mixture adjusting tool locates down the top of the carby where you top up the oil and and the needle is wound either up or down depending on the mixture. If I remember correctly as a starting point you wind the needle fully down and then back off 1 and a quarter to 1 and a half turns.
Also you may want check that the diaphrams are OK before doing any of this, just lift the lid off the carby and you will see it attached to the piston and needle. They are genuinly not that expensive so may be better to replace them anyway.
Hope this is of some help,
Casey

Posted: Sun May 01, 2005 10:04 am
by BIg StEvE
Cheers mate!

Yeah i read that i needed the tool but i never found out if it was goin to cost alot! When you explain it all like that it doesnt seem to hard so i'll give it a go!

Does any one have an idea on what one of these tools will cost?


Thanks again Casey

Posted: Sun May 01, 2005 7:28 pm
by Ralf the RR
Casey_leonard wrote:Hi Steve
Just in case you cant wait for the dealer or get someone to do it for you.
It requires 2 tools, one to do the mixture and one to do the balance.
The mixture adjusting tool can be purchased from a dealer, the balancing tool you may be able to purchase from your local parts place like Repco.
A peice of garden hose can be used for the balancing if you dont want to fork out for the proper tool.
Once you have the mixture set and the vehicle idling put one end of the hose to your ear and the other just in the entrance to the carby inlet (air filters removed of course).
You can now hear the amount of sucking each carby is doing and by adjusting the idle screws on each carby you can balance them.
i.e. if one carby is sucking harder than the other back off the idle screw and viser verser. Keep going back and forth until they both sound the same and your idle speed is correct.


Not quit right, but very close.

Slacken or remove the balance adjustment.
Adjust the idles as described.

The reconnect the balance and adjust it so that each carb is the same.

This is done at idle and various rev ranges.

I used to use a piece of vacuum hose. It fits in your ear nicely.
Just grip it about 1/2 to 1 inch from the end, and insert it down the throat.
Use the edge of your thumb as a reference to ensure it goes down each carb by the same amount

Now have a carb balancer. Much easier :lol:

Posted: Fri May 06, 2005 12:14 pm
by Casey_leonard
Yeh thanks Ralf, I forgot that part.
Casey[/code]