Webers

[sailing]

http://www.teglerizer.com/dcoe/dcoe45_tour.htm

This give a good guide to webers, how they work and the fuel flows

As far as I am concerned  at home you can only do the following.

1. Balance both sets of carbs.

2. You can adjust the air bleed screws to balance air within a carb and it partner barrel.

3. You can adjust the idle screws

4. You can adjust the Throttle position sensor (if you have one) .

After that it is all down to swapping and playing around with jets etc, and for this you need to be able know what effect each change is having. You also need to have lots of different jet available.

Basically this is where the rolling road comes in and tells what affect each change is having.

Unless you are some sort of ex top mechanic who has years of experience. I do not see how you can make judgement on jets without a rolling road and it would be a case of suck and see.

But read the attachment as it is important to understand what is going on inside  Webers' You will realise it is quite basic with little to go wrong once set up correctly.

I think you have to accept that the rolling road is the tool when playing with jet and stick to the basics of keeping the balance accurate.

Regards

Tony

[Blatman]

Blatters, but setting up triple webers on Astons in the late 50s early 60s without modern technology was done and it did take all day (or more) but we did it.

And I'm not saying anything to the contrary. If anything I am full of admiration for anyone who can set up Webers with nothing more than an ear and an A*** as the tools, and as Sailing has said, unless you have a TOP mechanic doing the listening and the driving, it'll never be right. And even if the TOP mechanic can get it right it's likely to take all day, meaning you have to pay for all day. But why would you stick with a tuning method from the 60's? I mean seriously...

With a rolling road, time to fix is decreased dramatically, and accuracy of the results is increased dramatically. But this "black art" stuff is the reason why so much garbage is talked about carb set up by mechanics these days. People are too willing to accept that it's a black art and will believe anything they are told. But fer gawds sake, this is the 21st century. We have accurate tools to use to take the guesswork out of carb set up and be able to monitor and prove the results without endangering the engine as we do so.

[rose5691]

Lots of useful stuff chaps, thanks        

[rose5691]

Adjust the IDLE MIXTURE.

Raise the idle speed to 1000-1500 rpm by turning the Idle Stop Screw. Stop the engine. Remove the spark plug wires from the two rear spark plugs and ground the wires. Turn each of the front two Idle Mixture Screws clockwise and count the number of turns until the Idle Mixture Screw touches its seat. Normally, this screw is about 3/4 of a turn from its seat.

Restart the engine. Adjust the two front idle mixture screws so that the engine rpm is the highest possible. Allow a few seconds after each adjustment for the engine to respond to the change.

Stop the engine. Reconnect the two rear plug wires, disconnect, and ground the two front plug wires. Adjust the two rear idle mixture screws.  

This was from the website

why and how would you ground the plug wires?

Also, would this method be more reliable than not removing them. I gues you've then got only 2 barrels to deal with instead of 4 so it's easier to "fine tune" the idle

[spacecadet]

http://www.teglerizer.com/dcoe/dcoe45_tour.htm

This give a good guide to webers, how they work and the fuel flows

As far as I am concerned  at home you can only do the following.

1. Balance both sets of carbs.

2. You can adjust the air bleed screws to balance air within a carb and it partner barrel.

3. You can adjust the idle screws

4. You can adjust the Throttle position sensor (if you have one) .

After that it is all down to swapping and playing around with jets etc, and for this you need to be able know what effect each change is having. You also need to have lots of different jet available.

Basically this is where the rolling road comes in and tells what affect each change is having.

Unless you are some sort of ex top mechanic who has years of experience. I do not see how you can make judgement on jets without a rolling road and it would be a case of suck and see.

But read the attachment as it is important to understand what is going on inside  Webers' You will realise it is quite basic with little to go wrong once set up correctly.

I think you have to accept that the rolling road is the tool when playing with jet and stick to the basics of keeping the balance accurate.

Regards

Tony

Sorry, dont agree with you....

I'm not a top mechanic, but I have got my webers running spot on myself  with the help of  a wideband lambda,

I have changed the idle jets, main jets, emulsion tubes, pump jets and pump bleeds , venturis, trumpet lengths.

All I which is was able to directly see the effect of by  driving aound and observing the datalogs.

[rose5691]

so what's a wide band lambda?

[Mark Stanton]

wide band lambda?

you'll make lots of new friends when you buy one        

[Norman Verona]

Blatman, I wasn't arguing, I mean, would I!

However, even with a fully computerized RR some young lads at a ex Caterham dealer in Chesterfield can't get it right.

There is a certain amount of experience required even with computers. It's translating the information being given that's the trick.

I was on one of the first courses for the new Crypton analiser in 1962 and you needed to interprate the info it was giving you. Took a while for that to sink in. Every new car tested had distributors outside the stated tolerances. I was changing them under warranty. After a few weeks of this it was explained that whilst the book spec was correct I must interperate the result of the test as a "anomoly with a new distributor".

[spacecadet]

so what's a wide band lambda?

a device for accurately and in-situ measuring the air-fuel ratio of the combustion process ie if its rich or lean.

Do a search here or on Google of go look at

http://www.wbo2.com

[sailing]

so what's a wide band lambda?

We have lots of them in the streets of Liverpool. Or were they Lambbannas??

Not sure if the were wide band or narrow band. You may need a narrow band one if you run a narrow body Westfield.

[Norman Verona]

This thread reminds me of the posting on the dark side which said "how do I bleed my brakes?"

My response was "If you have to ask you can't"