Hi,
After rebuilding, my car has driven only 60 km and I couldn't adjust my carbs yet.
First I want to adjust the screws for the air/fuel mixture of my SU carbs. I have no idea, from which point I should start. Actually they are about 4 turns out and sparks are looking black coated. I cant drive on the road yet, therefore I just need something like a standard adjustment. Can anybody give me a hint.
Thank you in advance
Kind regards
Christof
Adjusting my SU carbs
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four turns out on the main jet carrier screws (Iassume these are the ones you are referring to, bottom of carb directly under the needle) is a long way out but a safe plase to start. I assume you are trying to set an idle mixture only??
The easiest thing to do is get it started, ballance the carbs, filters off (use a piece of pipe to listen to the flow into the carbs, stick it near the bottom of the venturi and ajust idle screw so both sound the same, bit of time and care you can get them spot on. Aim for about 600 to 800 rpm fast idle.
Stick the filters back on and ajust the idle using the lifter pin under the piston on the carb. if the engine slows when you lift the pin it is too rich if it rises then falls it is right and if it speeds up it is too week. work methodically and alternate sides starting at the same point on both. From time to time open the throttle for 30 sec or so so you clear any residual fuel that collects in the manifold.
best of luck
Mike
The easiest thing to do is get it started, ballance the carbs, filters off (use a piece of pipe to listen to the flow into the carbs, stick it near the bottom of the venturi and ajust idle screw so both sound the same, bit of time and care you can get them spot on. Aim for about 600 to 800 rpm fast idle.
Stick the filters back on and ajust the idle using the lifter pin under the piston on the carb. if the engine slows when you lift the pin it is too rich if it rises then falls it is right and if it speeds up it is too week. work methodically and alternate sides starting at the same point on both. From time to time open the throttle for 30 sec or so so you clear any residual fuel that collects in the manifold.
best of luck
Mike
poppet valves rule!
Hi,
thank you for your answer.
It sounds that you are talking about different carbs than mine. Mine are SU Hif6 carbs and have small screws sideway for adjusting the mixture when idling, using a screwdriver to adjust. Your decripion is for a HS6 carb for example?
But most of the description fits to my carbs and rising the carb pistons is the way to find out if the mixture is too rich or too lean.
Thank you so far, any comment for the mixture screws?
Kind regards
Christof
thank you for your answer.
It sounds that you are talking about different carbs than mine. Mine are SU Hif6 carbs and have small screws sideway for adjusting the mixture when idling, using a screwdriver to adjust. Your decripion is for a HS6 carb for example?
But most of the description fits to my carbs and rising the carb pistons is the way to find out if the mixture is too rich or too lean.
Thank you so far, any comment for the mixture screws?
Kind regards
Christof
Google for Burlen and download their guides.
Mixture screws, remove piston and cover, adjust mixture screw until jet is flush with the bridge, use flat screwdriver end to gauge when jet starts to rise above bridge. Then turn mixture screw two turns clockwise. Make sure both carbs are set similarly interms of jet height and number of turns.
jw
Mixture screws, remove piston and cover, adjust mixture screw until jet is flush with the bridge, use flat screwdriver end to gauge when jet starts to rise above bridge. Then turn mixture screw two turns clockwise. Make sure both carbs are set similarly interms of jet height and number of turns.
jw
