Weber too lean issue?

[Grizzly]

Yes you heard right... Weber running too lean if you can believe it, never had a Lean problem that wasn't inlet o-rings.

I've just been playing with the +2 in an attempt to get an MOT on it and noticed there is some thing odd going on with the Carbs. I pulled the Spark plugs out and the two rears are Black as you would expect but the two front ones where clean (i mean no carbon deposits at all, look like new)

I thought some one was winding me up because it runs ok, so i put it all back and did a spray test looking for air leaks (Inlet O-rings where fine). So stuck the Colour tune in and adjusted the mixture rich and the colour tune wouldn't go Orange. (Odd)

Can get the rear carb adjusted quite well but the front one seems lean on both 1 and 2 cylinders.

It was getting late so didn't have too much of a play but i took the Idle jets out and they seem clean, things like the Float seem to be ok.

I can only assume some thing is blocked but it ran well before Christmas when the MOT ran out (serviced it new year and its only run in the garage every couple of weeks)

Its a weird one, i know most Elan owners are experts at setting Webers up so i thought i'd ask if there was some thing common.

Cheers.
Chris

[Concrete-crusher]

Hi Chris

I had a problem getting my colortune to work , it ended up too lean and poping really badly.

I then checked the timing and found it about 10 degrees too advanced. I had previously fitted an electronic pickup rather than points , so that explained the timing change.

Anyway , with the correct timing the colortune worked and no poping

Steve

[Chancer]

Carb balance.

The lean carb has its butterflies closed compared to the other, air is being dragged through it by the healthy pair of cylinders but its not picking up enough fuel.

Always balance carbs before twiddling.

[alan.barker]

filter blocked at fuel inlet of front carb
Alan

[gjz30075]

Remove the transition hole plug and look at the throttle plate position in the first hole. Where is it in
relation to the rear carbs' throttle plates?

[Grizzly]

Thanks for all the suggestions, i went through them all and i'm fairly sure the Butterfly's are sticking.

I took the transition hole plug's out and straight away noticed the front carb's throttles was not fully closed, so flicked them closed a couple of times and it started to behave, only problem is first time i drove it out of the garage it did it again.

So does that sound like it needs a rebuild? i'm guessing its just stuck with being sat for a while but its strange how the revs don't change by a huge amount (50-100rpm if that) do you think it would help giving it some light oil or a good carb cleaner session?

[billwill]

Before going to the bother of dismantling the carbs, I would be inclined to try:

Put Plus-gas on the carb spindle bearings & waggle them to & fro for a while, them put some light oil on the bearings to wash the plus-gas out.

[ort]

Chris
check the spindle bearing cover washer is not binding on the body or bearing cover.