Cylinder head cover & fuel pump questions

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From the cylinder head cover there is a small hose connected to the original air filter.

I have weber carbs with their individual air filters. I had originally connected this hose to one of the carbs and found out that after a while there was oil collected in that carb. I disconnected this hose and replaced it with a longer one that now simply 'hangs' there.

Question, should/must this hose be connected to anything? Is the fact that oil was being collected (after a while) in the carburetor indicative of anything?

Fuel pump question.

I have a mechanical fuel pump. If I let the car 'sit' for a week or two it takes a while to start the car until gas is delivered to the carbs. Sometimes to the point it almost drains the battery.

I'm considering installing an electric fuel pump to deliver gas but still keep the mechanical fuel pump. To be clear, the electric fuel pump would deliver the gas to the mechanical fuel pump. Any problems with this set up?

Some may suggest to have only the electric fuel pump but then the mechanical pump would still be operating without fuel being there and would probably dry out the diaphragm.

Any thoughts?
 
Put a small air filter to that hose, otherwise it will leave your engine compartment getting quite messy after a while - and in many places it is a must have due to legislation. That said it is also very risky if your car spills oil to the ground, biekrs driving the same road can easily slide on that oil, fall and get seriously injured

Install a one-way valve on the gas hose coming from the tank, that will prevent all the gas in it to sip back to ground level. For anything less than 220 bhp, there is no need for a EFP.

Cheers
A
 
Check all fuel lines and attachment points from the tank to the carbs to ensure you are not sucking any air.
 
andre said:
Fuel pump question.

I have a mechanical fuel pump. If I let the car 'sit' for a week or two it takes a while to start the car until gas is delivered to the carbs. Sometimes to the point it almost drains the battery.
Click to expand...

Check/replace your accelerator pump diaphragms. Maybe install a pressure gage between the pump and carbs to make sure the pump is putting out ~2.5psi.
 
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David,

Sorry, but what do you mean by "accelerator pump"? Where is this located? Maybe I know it under a different name or do you mean the fuel pump itself?

The fuel pump is less than a year old and it works well once the car is started. There are no fuel leaks/odor anywhere.
 
Each carburetor has an accel pump that sprays fuel into the primary barrel upon acceleration, take the air cleaners off and look down the primary barrels of each carb, when the throttle is moved quickly you should see a squirt of fuel. Usually this is a symptom of hesitating acceleration but you never know.

andre said:
David,

Sorry, but what do you mean by "accelerator pump"? Where is this located? Maybe I know it under a different name or do you mean the fuel pump itself?

The fuel pump is less than a year old and it works well once the car is started. There are no fuel leaks/odor anywhere.
Click to expand...
 
Thanks Dave,

Yes those are the carbs I have ( Auto. choke) I did replace this diaphragm on the front carb couple of years ago. Don't t recall if I did it on rear carb.

I would think fuel would leak from there if the diaphragm was broken as this is why I had changed the front one. There is no fuel odor or leak that I can see but will check anyway.

To Steve's point, yes fuel does squirt when I move the throttle.

The problem I'm having is if the car sits for a week or so there is no fuel in the fuel filter ( I have a clear plastic filter) and it takes awhile for the fuel to reach it and start the car.

This is why was considering installing an Electric pump and leave the mechanical pump functioning as well but wasn't sure if that set up would be a problem.
 
I would look at the fuel pressure and accelerator diagphrams before trying anything exotic. These cars were designed to work w/o double pumps and one way valves. Here is my in-line fuel gauge:



IMG_0347.jpg
 
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