Weber question

[sammaw@bellsout]

I am trying to get the DGR carb working right, and was wondering what jet sizes and needle seat orifice is a sucessful setup for those of you using the DG series carb?

Thanks for your insight

Sam

 

[JJames]

I'm doing the same thing with a 40DF. I have
F7 E-tube
Accelorator pump 50
Idle jets 65
Mains 130
Airs 160
Needle Valve 175

I would appreciate any help though, as it isn't quite right with this set up.

 

[RootesRacer]

I am trying to get the DGR carb working right, and was wondering what jet sizes and needle seat orifice is a sucessful setup for those of you using the DG series carb?

Thanks for your insight

Sam

The jetting is application specific so cant help you there (knowing your venturi sizes would allow a good guess though).

The needle and seat would work well at 1.75 to 2.00 however.

 

[64beam]

Hi Sam,

When I installed the DGV on my Alpine, the carburettor setup was standard. The stock setup can be found on the internet, but as stated by RootesRacer, these Webers are used on a wide variety of applications. What I found was that the standard setup is very close to what we need, but there is a slight hesitation when accelerating. A few people including myself, have tinkered with the idle jets to rectify this issue. I'm not sure what the difference is between the DGR to DGV.

Hope this helps,

Regards, Robin.

 

[RootesRich]

There is no difference in design between a DGR and a DGV. The DGRs are older with production ceasing in the early 80's and the quality of construction is higher compared to DGVs made today.

Sam, if you PM me your engine size, performance modifications (if any) and your altitude, I can provide baseline jetting recommendations to get you started.

 

[sammaw@bellsout]

I looked at he jets on the carb, and also talked with a tech guy at Pierce Manifold. The are the supplier of Webers to Sunbeam Specialties, and indicated this is the setup they sell them for Alpines.

Here are is whats in the carb vs Pierce

My Carb Pierce recommendation

Main Fuel Jet 125 140
Sec Fuel jet 130 135

Air correction

primary 180 165
secondary 180 160

Idle Jet Primary 55 55
Idle jet Secondary 50 50

Needle valve is 200 ? (forgot to ask)


Are these values close enough? Or should I be ordering some jets?

Thanks much for your advice.

Sam

 

[Bill Blue]

Sam, for what's its worth (not much, I know) at one point I had my carb jetted very close to the Pierce values. It was too rich, would load up on long uphill pulls, got bad gas mileage. I ended up with 125 main, 140 secondary, with 170 and 180 air correction jets, F50 emulsion tubes and 50 idle jets, all of which is pretty close to your carb. Of course, this is on a Ford 2.0, so direct comparisons are not possible, but if I had to choose a setup to run in a 1725, it would be yours, not Pierce's.

You say you are trying to get it working right, what is your problem?

Bill

 

[sammaw@bellsout]

The symptoms are mainly noticed on a cold start. It will fire, catch, run a moment, roughly, shut off, It will do this for several (sometimes many start attempts, then amazingly seem to settle down and run ok. I tend to start it with about 1/4 to 1/2 choke, then open the choke as it sputters out.

The plugs are carboned up after a short runtime, so I turned the mix screw in about another quarter, and cleaned the plugs.

I also wonder if this is not timing related, due to the roughness when it does fire.

 

[Bill Blue]

Sam, what happens if you try to start it by simply giving the carb one pump, no choke, hold the gas open a little. That will start my car every time in warm weather. Runs a little rough for a few seconds, need to give it gas to keep it going.

If that does not work, have you tried starting with full choke? How many turns out do you have the idle mix screw?

An engine has to be way out of time to cause rough running. You'd notice a lack of power, kicking back on the starter or overheating.

Bill

 

[sammaw@bellsout]

I've been out fooling around with it, and I have discovered that there is a vacuum leak thru the vacuum advance on the distributor. I know it was fine when I did the engine work, but must have given up the ghost. I imagine this could be the root of my problem. Next I will put the carb back together, plug the vacuum line, and see if it starts normally.