DCOE trouble/qusetion

[Guest]

I justr put a used but in excellent shape 40DCOE on the car. It was one off of a dual set up. Can I run it w/o any chenges or will I need to jet it? Seems a bit boggy. That may be from some walnut shells that made their way in the carb by accident. Still need to get the right cable to drive it. I have 5- 40's right now. Two have 30 venturis and the others 32's. One's a Dellorto but not using that one. Exhaust is clean. Adding choke doesn't seem to help.

I'm at sea level, have a 119 main jet. I'll dig in it and find the other info.

Just put in a 130 and a 50F9 ( I think0 and it runs alot better. Gotta go to bed now. 4:30 comes awful early.

 

[twas_brillig]

Have a look-see at these two threads:

https://www.britishcarforum.com/bcforum/u...948_#Post540937

and

https://www.britishcarforum.com/bcforum/u...r_a_#Post529000

I think there's enough reference material to keep you busy and confused for a bit. Please keep us updated as to how things work out, as I'm still a year away from our 45 DCOE.

Regards walnut shells: well, I've heard of it raining cats and dogs, and worries about driving through really deep poodles after such a rainstorm, but walnuts? (pardon my weakness for plays on words - I do know that they're used as a blasting media for small and huge projects)

Doug

 

[BlueMax]

According to the Weber manual, Austin Healey Sprites with 1275 standard engines should be using a 45DCOE 13, carburetor part number 19600.022, 13 designates the progression idle ports. Your float settings should be taken by holding carburetor top in a vertical position (A) which is the closest to body top is 7mm, setting (B) is the furthest from the body 15mm and your stroke should be 7.5mm to 8mm.

Your jetting should go as follows:

Choke: 34
SEC Ven: 3.5
Main: 130
Emul: F2
Air Corr: 175
Idle: 50F9
Pump: 50
Inlet Valve/ Needle Seat: 50

All of the settings were written when we had real gas, not gasohol; As well you should have substantial compression with the proper valve lash, timing and advance curve. This will give you at least a good starting base to work with. However I would completely disassemble the carburetor and thoroughly clean, blow dry an lube all components. Do not forget that the throttle shaft is using ball bearings and has a leather seal at both ends that should be flexible oiled to properly seal throttle shaft for your settings to be accurate.

Good Luck!

 

[Guest]

I've got a 1500. I plan to clean it. Didn't knnow about the bearings, thanks.

 

[BlueMax]

With this very trick 1380 I plan to use.


Choke: 36mm
Air: 140
Emul: F16
Sec Ven: 3.5
Idle: 45f9
Pump: 50
Inlet Valve:50

1.5 Velocity Stacks.

 

[twas_brillig]

Goshdarn, Bluemax - that 1380 picture is definitely porn for us old guys!

Kellysguy: the bearings on the weber throttle shaft were what persuaded me to say goodbye to the leaky (both before and after the machine shop....) throttle plate shafts on the SUs way back in the 70s and buy a Weber 40 DCOE for our stock 948.

Doug

 

[BlueMax]

Doug, I’m not to sure how old you are, but I’m no spring chicken by any long shot, but thanks for the complement! You’re absolutely right; once you have a DCOE dialed in you can forget having to worry about settings or wearing one out. Just keep a clean fuel filter an air filter and keep your engine healthy for many care free miles of enjoyment!

 

[Guest]

I like the carb already. I plan on going FI later, but if it works as well as I think it will, I probably won't inject it. MAN! So easy to change jets! I can change them almost as quick as my boss changes his mind.

 

[BlueMax]

Kellysguy, if you feel you needed a little more carb you can do something like this! You sure wouldn't need FI running this...

 

[Guest]

Went for a quick test drive, WOW! My favorite by far. Still need a bit of bug chasing on linkage and such., Runs great, still needs a tear down and final jet tweak but seems to be pretty close. Put the 45F9 back in as all charts I've seen use that one; runs better.

 

[twas_brillig]

BlueMax: what is that thing? Shouldn't there be another exhaust header?
Doug