Webers : fuel forming outside the carbs

[OldBob]

Any Weber owners had this problem ?

TR6 with triple 40DCOE, 32mm chokes.

Fuel is forming just under the joint between the front flange of the carb body and where the trumpet feeds in, then running back under the carb body.  Its not massive amounts but enough to be a concern.

I have checked float level = 8.5mm closed (Spain model Weber with plastic float).   Also have fuel pressure set to 3 psi 

I've tried sealing the trumpets into the carbs temporarily just to see effects but fuel still gets out. Its not happenning every trip and not to every carb each time. Mostly its the forward carb thats worse which is where the fuel enters the rail on my car.

Carbs were fully professionally stripped & rebuilt with new float cut-off valves a year ago and can't say I noticed this back then - but I did notice an increase in fuel consumption about that time.

For filters I currently have a set of Ramair sponge socks fitted but also have a set of mesh trumpet end caps which I abandoned after being advised they don't allow good air flow into the trumpet.

Any previous experiences like this and the solution much appreciated.

Bob

 

 

 

[Hamish]

This guys videos are great worth a watch there are a series on the webers  

 

I have had to change my Spanish Weber floats twice. They are crap. 

Edited April 12 by Hamish

[stuart]

Float levels and fuel pressure, do you run a pressure regulator? If your running foam socks be very careful if they’re getting any fuel on them as that’s an accident waiting to happen 

Stuart

Edited April 12 by stuart

[OldBob]

1 hour ago, stuart said:

Float levels and fuel pressure, do you run a pressure regulator? If your running foam socks be very careful if they’re getting any fuel on them as that’s an accident waiting to happen 

Stuart

Yes Stuart, regulator fitted set to 3psi. Just see in in the photo.

Mesh filters are back on although guess that doesn't completely cancel out the hazard.

Edited April 12 by OldBob

[stuart]

16 hours ago, OldBob said:

Yes Stuart, regulator fitted set to 3psi. Just see in in the photo.

Mesh filters are back on although guess that doesn't completely cancel out the hazard.

TBH I think thats the wrong place to mount that regulator as the engine vibration wont help for a start and those Sytec regulators arent as good as they used to be, I think you`d be better of with a Malpassi type bolted to the wheel arch like I had on my 250. See picture below. FWIW I do have a brand new one in stock.

Stuart.

 

[unclepete]

Stuart

I notice you have the K&N ? air filters fitted on your set up. Have you installed them with the short trumpets? 

If so does it make much difference to the airflow vs Bobs long trumpet install?

[stuart]

7 minutes ago, unclepete said:

Stuart

I notice you have the K&N ? air filters fitted on your set up. Have you installed them with the short trumpets? 

If so does it make much difference to the airflow vs Bobs long trumpet install?

IIRC there wasnt any fitted, it still went like stink, cars long gone now and I believe the new owner took them off and put a pair of SU on instead ☹️

Stuart.

[iani]

25 minutes ago, unclepete said:

Stuart

I notice you have the K&N ? air filters fitted on your set up. Have you installed them with the short trumpets? 

 

If so does it make much difference to the airflow vs Bobs long trumpet install?

I run 12mm trumpets inside the K&N's on my DCOE 40's fitted to my GT6 without any issues, the car produces 192bhp & 165 ftlbs torque from its 2.5 lump, the fuelling must be ok 😀

[WELLSY]

Hello Bob 

I have had similar issues on my  webers set up for years, never really slved the problem

You could try the following.

Reduce fuel pressure to 1.5/2. 

Fit a heat sheild underneath it also catches any dribbles.

I removed the enrichment/choke mechanism

Misab plates between the manifold and carb

Check gaskets on bottom of carbs.

D3sshooter has a vid on flooding and fuel vaporisation might be helpful.

Good luck

Simon