SU Carb Diagram

Is there a good reference tha shows the different connections for a SU Carb?

Fuel Inlet, Vent Tube, Balance Tubes, etc.

Thanks,

Bob

 

take a picture of your carb, put numbers on the things you're confused about, and we'll tell you what is what

 

http://www.sw-em.com/su_carbs.htm

everything you wanted know but were affraid to ask.





http://www.sw-em.com/SU Carb Service.htm

 

Jim,

Thanks, I will get some pictures tomorrow when I' at the garage where engine/carbs are.

Bob

 

With all due respect, an answer would be easier if the question were a bit more specific. There are quite a few DIFFERENT types of SU carburetors. Listing a few:

D
DU
H
HD
HIF
HS
HSAED
HV
HVD
HVS
MC
OM
UB
UBA

Jon

 

Try also the Burlens website and the Des Hammill book on power tuning SUs. The Haynes SU manual is very good too.

For needle selection try the mintylamb website tools.

 

The cards are "HIF" models.

I have attached a pictue of one of the carbs.

 

Do a search of SU HIF diagram

Here is one:

http://www.7ent.com/pages/articles-tech-tips/diagram-hif-carburetor.html

Jon.

 

That doesn't answer his question....which is about which tubes do what?

Probably the best way to answer the question is to take it apart and see where the tubes go. The one(s) that go to the needle valve is the fuel inlet, if there is one that goes to the top of the float chamber it's the vent. A balance tube would connect to the main throttle bore.

 

The design of the SU carb is straightforward and is not complicated to work on. Making it work right requires things like checking for throttle shaft wear, bent needle, jet centering, free movement of the dashpot, proper mixture adjustment, and balanced adjustment of mixture and linkage adjustment of multiple carbs.

Properly maintained and adjusted SU carbs work well, and are not temperamental as many claim.

 

I have twin SUs on one of my cars, cold or hot, all I ever need to do is a quick tap on the key and she running. I love that!

 

i have these on my datsun 1600 and mine allways wants to fight with me to start! i got to do something.

 

I had to retrain myself on starting my car with SU's. Like RagtopRides said just turn the key and leave your foot away from the accelerator pedal. All that does is add more air and the car won't start! Balanced them once, top off the dashpots occasionally and they work like a charm.

 

Another source
http://www.piercemanifolds.com/

 

Lower front 6mm brass tube is fuel inlet. Upper front tube is a vent for the float chamber (can be used to pressurise the chamber in supercharged applications) - just fit a small mesh filter. Upper rear tube needs to be capped as it was used as either a vacuum source or a balance in some original applications. Smaller tubes on the rear mounting flange are for vacuum advance.

Pull the dashpot, remove the piston and the float chamber lid and all will become obvious.

 

Thanks for the help. I think I have a handle on this now.

I fould a useful manual at http://www.v8register.net/FilesV8WN/SUbookletsAUC9939AHIFtuningandservicing.pdf

I am installing these carbs on my Model A (Model B Engine, McDowell Overhead Valve Head, Solid State Ignition, etc).