Carb Springs

[Andrew S]

Quick question.

The large spring inside the carbs, what length should they be. one of mine is 8 inches, the other is 9 inches and my friends Stag is just over 6 inches. On the basis that they restrict the needle lifting, they are at different rates and not sure what they should be and if they have been stretched, then the needles wont lift for performance and when they do, they may be an imbalance

Cheers

Andrew

[Tdm]

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Let you have a look at mine when your over Andrew, & I'll let you measure as well!

[DJT]

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Terry wrote:

Let you have a look at mine when your over Andrew, & I'll let you measure as well!

:shock::shock::shock::shock::shock::?

[Tdm]

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DJT wrote:

Terry wrote:

Let you have a look at mine when your over Andrew, & I'll let you measure as well!

:shock::shock::shock::shock::shock::?

The missing word is "springs" - funny how you can omit a word from a sentance & change the whole meaning! Then again it depends on the mind of the reader & how they think!

[Andrew S]

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After reading the topic about what oil to use in carbs has got me thinking again about these springs as bothtopics I think relate to performance.

The purpose of the large springs is to prevent the damper lifting to easily. Hence my comments about the lengths of my springs differing meaning that one damper would be at a different level as the other and therefore mixture would be wrong.

Likewise with the oil that is used, Engine oil is too think when cold, so bad performance fromcold. The idea of both the oil and springs would allow a controlled floating of the damper / needle to evenly rely on the balanced vacuumsetting for each carb intake.

Is there any literature that shows the spec for the length of the springs?

Cheers

Andrew

[V Mad]

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The Stromberg CD carb works on the constant depression (hence CD)principle where the piston rises or drops until it reaches a steady state where the desired vacuum (or depression)is reached. The tension of the spring is not critical, and should not normallyaffect the piston position for a given throttle opening. It is likely that the longer spring has justbeen stretched. If your pistons are not lifting to the same rate during engine running, check that both throttle flaps open the same amount. Also checkthere are no other restrictions like twisteddiaphragms.

[Andrew S]

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Thanks and interesting

The car is running well and it was only the fact that I have just rebuilt the engine and the carbs are not balanced and my intention was to do so this weekend that I noticed the different lengths and was wondering if I was going to waste my time

Thanks for that, wont worry now

Cheers

Andrew

[V8 Rumbler]

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Andrew S wrote:

Thanks and interesting

The car is running well and it was only the fact that I have just rebuilt the engine and the carbs are not balanced and my intention was to do so this weekend that I noticed the different lengths and was wondering if I was going to waste my time

Thanks for that, wont worry now

Cheers

Andrew

Hi I would not agree with what you have said about the oil. Normal engine oil is what you should be using. Thinner oil can be used as an attept to conpensate for carbs in poor condition.If there pistons do not rise/fall evenly the most common reason would be dirt inside the carbs. have you cleaned them with carbs cleaner? or felt the sides of the piston/cylinder for raised areas etc?

Darren

[Andrew S]

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Hi Darren

I have used engibe oil in the past and thepick up to me seemed flatter with the thicker oil and whilst my rubber o rings are in good nick and dont leak oil,I was going to continue to use ATF. If you think that its wirth trying engine oil again I may give it a spin. My pistons lift and drop perfectly.

Cheers

Andrew