1968 L71 Crankcase full of fuel

[Steve P.]

Just acquired a 1968 L71 Convert for our collection: Top Flight, Bloomington Gold, Triple Crown that has been sitting for a while. After getting it running, while sitting over night, the carbs leaked down and completely filled the crankcase and open cylinders with fuel. Luckily I picked up on it before starting. Drained the crankcase, removed plugs and cranked over to blow out fuel, cranked new oil through the engine and drained. I have ordered Holley carb kits, new OEM fuel pump. While removing carbs. I noticed there was still fuel running out of the fuel line from the old pump. It continued until I put a plug in it. I thought the issue might be a stuck needle.The carbs, fuel, and fuel lines look very clean. I checked the fuel cap, vents one way, air in but cannot blow through to atmosphere. Our shop is very capable but we have limited experience with this engine package. The thought of doing anything that might break this beauty makes me sick. Any help or advice would be greatly appreciated and thanks in advance.
Steve Pugsley

[Daniel S.]

Re: 1968 L71 Crankcase full of fuel

My 68 L71 does the same thing if the fuel tank is full and the nose is pointing down hill at all. In fact this will begin to occur even when the vehicle is level but the fuel tank it filled to the bottom of the filler neck. Under these scenerios, the fuel is higher than the carbs so gravity does what it does best. I have never looked into a permanent fix, but rather make sure to not duplicate thses situations.
In my case a new fuel pump did not make a difference.
Glad you caught it before starting the car.

[Steve P.]

Re: 1968 L71 Crankcase full of fuel

My 68 L71 does the same thing if the fuel tank is full and the nose is pointing down hill at all. In fact this will begin to occur even when the vehicle is level but the fuel tank it filled to the bottom of the filler neck. Under these scenerios, the fuel is higher than the carbs so gravity does what it does best. I have never looked into a permanent fix, but rather make sure to not duplicate thses situations.
In my case a new fuel pump did not make a difference.
Glad you caught it before starting the car.

Thanks for the quick response.....................I am currently researching a 12V in line fuel cut off valve that would open and close with the key switch or a hidden toggle switch that could double as a theft deterrent. I can pass on what I come up with if you are interested.

[Rich G.]

Re: 1968 L71 Crankcase full of fuel

I have a 68 L71 and have not seen this although I rarely if ever fill the tank. Usually sits half full, sometimes weeks at a time.

Rich

[Larry E.]

Re: 1968 L71 Crankcase full of fuel

This happened to me once with my 68 L68. I had loaded it on a trailer too early before I left and the weather was very hot which
made it worse. Larry