Weber’s turning yellow in 700 miles

too much B in the gas

 

my bad attempt at humor
B as in B vitamin.

 

Was the metal clear coated? Looks like poly decomposing from heat.

 

Judging by the photos I suspect a light coating of oil residue on the surface of the carbs (possibly when installed) has heated and varnished over making the carbs a little golden in colour.

 

I'm going with colorization from either heating vapors or residual fluid coatings.

 

Call it a patina and admire it.

 

I would think that if it was fuel related, the intake manifold would also be yellow from the same contamination. You didn't mention the carb was leaking fuel and it doesn't appear that the engine has been engulfed in flames recently, so I doubt there's a fuel contamination issue. Then again, it's a carburetor and they leak. If you smell gas when the car shuts down, maybe there is some surface tension action causing fuel to coat the thing.

 

Image Unavailable, Please Login
I think it’s something you just have to live with , as long as works the motor runs good etc ,
I be cleaned mine up since this pic .If you take the air-box off the top of the venturis and sides of the butterflies are similar.
So for me it’s fuel related gum residue .
Have you tried wiping it off ( when cold ) with acetone and a cotton bud ?

 

Same thing happened to mine within a year after being cleaned and rebuilt.


Regards
David

 

I'd consider it patina too. Looks nice.

 

Looks normal to me - Carter AFB/AVS carbs always looked like after a few miles! Then again I don't know about Webers - never owned a vehicle that used them. Are they aluminum (like Carters)? Holleys didn't look that way because the metal was a bit yellow-ish anyway.

 

Ask Martin, he has this all figured out. He keeps them in a glass case in his living room, still immaculate! ;-) Likely a bit of fine dust and fuel fumes. Spray with carb cleaner and see if it comes clean.

 

Didn't Weber's have a brownish hue from the factory? Look at the trumpets (?) on top. Mine on my '79 were a golden brownish color and were perfect.

I was told, by a shop that does restoration for the Collier collection, now the Rev's Institute, that when made, the castings were impregnated with a certain kind of oil in the mould release which gave them the peculiar color.

It's the same color as a Rochester Q Jet, or a Holley. If they were bare gray metal after service, maybe the "original" color was removed.

Here's a pic of mine. Image Unavailable, Please Login

 

LOL!
I think it's absolutely normal, that the carbs get that yellowish hue while in service. There's always fuel vapor around the carbs. On my freshly cleaned carbs it began around the throttle bearings. After shut down of the hot engine there's always fuel vapor leaking a bit there.

Again my living room carburettor display :

Image Unavailable, Please Login

Best
Martin