Re: Larry's 1951 Club Sedan Project

Posted by Larry51 On 2015/2/20 0:15:32

The '51 has been running well and I've clocked up around 300miles since it was registered. Mostly very enjoyable driving!

There have been a few problems, he most inconvenient being range on fuel is only about 80 miles. I was sure that was caused by a hole in the petrol pickup tube because every time I was refilling the tank petrol started coming up the filler spout after around 4-5 gallons were added. Even adding very slowly it was always the case of fuel coming back at you from the spout, and the tank just would not take any more. "No 'airlock' could be that persistent" I thought.

So I was ready to take the tank out, cut a hole and fix the pickup tube . . . until a few days ago when thinking: what it I find no problem with the pickup tube? So, how do I prove it is the pickup?

I took a Jerry can and topped up my tank, which SHOULD have been completely full after the last drive / top-up at a servo. Around 35 litres (8 gallons) later I knew my problem was an air lock that was happening every time I refilled the tank (- no matter how carefully). Strange because one time a few months ago I blew air down the breather to test and there was no blockage.

So, got under the car and took the rubber hose off the breather-to-tank pipes and blew through it / sucked through it. No blockage. So, question is: why the almost constant airlock problem?

A friend with a '51 tells me that Packard placed a whistle in the breather pipe, which was to alert you when the tank was nearly full. I can't tell if there's a whistle in there or not. If there is, maybe it creates just enough back-pressure to cause an airlock.

Now I need to figure out how to overcome this airlock problem. The only idea so far is to change the existing breather to make it more effective. I wonder how?

Have posted to see what ideas other have.