MGB & GT Forum

Car: 1977 MGB de-smogged with Weber DGV conversion by PO otherwise stock
Task: Fit new aftermarket valve cover with vented cap (old one is a mess)
Concern: Dorking up crankcase ventilation and an otherwise fine running engine
Question: Could one reroute the purge line (discharge) from the evap canister (formerly flowing into the valve cover restrictor pipe) directly to the input connection (elbow) on the underside of the Weber where the crankcase vapors are drawn in ?
Hypothesis: Yes
Rationale: a) The new vented cap would regulate intake of fresh are to the crankcase (in place of the restrictor on the stock cover) b) the residual fuel vapor not absorbed by the charcoal in the evap can would have negligible effect on combustion air intake c) following the John Twist recommendation to replace the small plastic elbow on the Weber with a larger 1/2-inch fitting - why not use a "Y" split fitting with inlets from crank and evap can ?
Why?: I dont want to drill and tap the evap hose into new valve cover and fabricate the restrictor it would need (?)

This MGB newby is positively identified...experts are cleared "hot"...fire at will...

Go to the Tech Library (black menu bar at the top of this page) go to Carburetors and fuel and look for Weber Hose Routing. You will find the correct way to set up your 1977 system. This is the tried and true method when using a Weber DGV down draft carb. No vented cap. Air in through the valve cover, vapours out through the tappet vent tube to the carburetor air cleaner.