Hi,

My fuel pump is leaking from what appear to be 2 "vent holes" just above the outlet that goes to the carburator. Anyone have any ideas what these holes are meant for? The 55 service manual I have does not have any info on this. My thought is perhaps there is some type of valve on the other side of the holes that lets gas out if too much pressure builds up in the pump.

Anyone know where I can get a rebuild kit or pump replacement?

Note: this fuel pump also provides vacuum for the wipers. Concours has a repalcement pump but it will not provide vacuum for the wipers.

 

tHERE IS AN OLD TIMER HERE IN mASSILLON OHIO WHO REBUILDS THEM FROM HIS HOME. HE RETIRED A FEW YEARS BACK. I TOOK MINE TO HIM TODAY. $65.00 AND ITS GOOD AS NEW.

 

Take a look in my gallery at the "54 Vacuum Fuel Pump" section. I just rebuilt this one for my engine. If it is the same, look at the 4th picture. Are these the holes you are refering to?

If so, yes, these are vent holes. However, there is no pressure release valve inside. Basically, these holes will allow the air pressure on the non-fuel side of the diaphram to stay equalized as the diaphram flexes up and down to pump the gas. These air holes also vent directly into the chamber that has the activation lever which comes straight off the cam shaft which has oil running through the timing chain area. The lever provides a channel for oil to run into this area of the fuel pump to keep the lever action oiled. This oil then can drain back into the timing chain cover area. If you have gas here, does it also seem to be oily? Have you checked/changed your oil lately and noticed anything different?

This is a long way to say that I believe the diaphram has worn out and leaks. Yes it can be rebuilt and one of the pictures shows the kit I bought from Dennis Carpenter. As of this summer, I know they had at least three more kits on the shelf as they erroneously sent me 4 kits with my order - I sent three of them back.

I have 82 pictures of my rebuild at 25.7 megs. If you need reference pictures, send me a PM and we can work something out.

 

I took the pump apart and there are cracks in the diaphragm which permits gas to get through and then goes out the vent holes you mention.

My pump is different from the yours and the rebuild kits I've found don't appear to be suitable for the pump I have. Best I can tell it must be a non OEM.

Thanks for your help.

-Jim