Fix for leaking float chamber

[Fred Winterburn]

Hello Folks,

I finally had enough of my front H6 carburetor leaking where the float chamber attaches to the carb body. I've gone through two new sets of the rubber top hat shaped grommets which I'm convinced were made just a little too small. The last fix I used was to add a small diameter O-ring between the rubber grommets to stiffen the whole assembly somewhat but not interfere with fuel flow. This fix lasted one year until it started leaking again last night.

For some reason the hole through the front float chamber was made ever-so-slightly larger than the same hole on the chamber for the rear carburetor, by just a few thousands of an inch. Manufacturing tolerance I presume.

Today, I sleeved the float chamber hole with a short piece of 1/2 inch copper pipe. I reamed the existing hole in the float chamber slighty larger, such that the copper pipe would be an interference fit into the hole. I cut a piece of copper pipe slightly longer than the length required, and drilled a hole in the side of it to line up with the gasoline entry hole in the float chamber. I filed a slight taper on the leading edge to get it started in the hole and then pressed it into place so that it was sittling proud on both sides. I then trimmed it carefully on both sides. The hole through the float chamber is now slightly less than 1/2 inch diameter, and the grommets hug the bolt tightly for a good seal. With a bit of oil to ease assembly it went together well and doesn't leak. For now anyway. The float chamber doesn't flop about as easily anyway so I have some confidence it will work. Take care, Fred Winterburn (1956 Morgan Plus 4)

[Fred Winterburn]

I realized that I made a slight error in my post. I said:The hole through the float chamber is now slightly less than 1/2 inch diameter, and the grommets hug the bolt tightly for a good seal. I should have said the hole is slightly smaller than it was previously. I didn't actually measure it. Fred

 

Hello Folks,

I finally had enough of my front H6 carburetor leaking where the float chamber attaches to the carb body. I've gone through two new sets of the rubber top hat shaped grommets which I'm convinced were made just a little too small. The last fix I used was to add a small diameter O-ring between the rubber grommets to stiffen the whole assembly somewhat but not interfere with fuel flow. This fix lasted one year until it started leaking again last night.

For some reason the hole through the front float chamber was made ever-so-slightly larger than the same hole on the chamber for the rear carburetor, by just a few thousands of an inch. Manufacturing tolerance I presume.

Today, I sleeved the float chamber hole with a short piece of 1/2 inch copper pipe. I reamed the existing hole in the float chamber slighty larger, such that the copper pipe would be an interference fit into the hole. I cut a piece of copper pipe slightly longer than the length required, and drilled a hole in the side of it to line up with the gasoline entry hole in the float chamber. I filed a slight taper on the leading edge to get it started in the hole and then pressed it into place so that it was sittling proud on both sides. I then trimmed it carefully on both sides. The hole through the float chamber is now slightly less than 1/2 inch diameter, and the grommets hug the bolt tightly for a good seal. With a bit of oil to ease assembly it went together well and doesn't leak. For now anyway. The float chamber doesn't flop about as easily anyway so I have some confidence it will work. Take care, Fred Winterburn (1956 Morgan Plus 4)

 

[Trevor S]

Thanks for that Fred. My new to the road TR2 started to suffer with a leak in the same place. I have replaced the rubber grommet and so far it has cured it but I will keep a copy of your post for future reference in case I suffer the same long term problem. Thanks

[littlejim]

Fred,

I think you are on the way to qualifying for the 'bush mechanic's' hall of fame.

One of Oz's best wrote a book 'Son of the Red Centre' about bush bashing by truck in the Top End early last century before there were any real roads. During one stop he was cleaning the clogged carby in the middle of nowhere and when he swatted a cloud of bush flies off his face lost the float needle in the spinifex.

He whittled a replacement one out of a mulga root and continued his journey to Darwin.

[Fred Winterburn]

Littlejim,

You are too kind. I'm not in that esteemed company. I have a friend who was stranded on the side of the road with a sixties vintage Datsun (can't remember the model). He determined that he wasn't getting fuel and that the pump which was a sealed unit had failed, but it was a valve inside the sealed unit that wasn't working, not the diaphragm. He hitch hiked up the road to a gas station and bought two PCV valves and enough hose to do the trick. He plumbed one in at the inlet and another at the outlet, since he didn't know which valve had failed. These two check valves allowed the pump to work and he made it home. Then there was the Eskimo that was stranded in the far north with a broken spring on the points for his snowmobile engine. He whittled a new one out of a piece of whale bone, and he too made it home, alive. Nope, I'd have hitchhiked all of the way home and spent two days getting the old car going, or frozen to death on the Tundra. Thanks though, Fred

Fred,

I think you are on the way to qualifying for the 'bush mechanic's' hall of fame.

One of Oz's best wrote a book 'Son of the Red Centre' about bush bashing by truck in the Top End early last century before there were any real roads. During one stop he was cleaning the clogged carby in the middle of nowhere and when he swatted a cloud of bush flies off his face lost the float needle in the spinifex.

He whittled a replacement one out of a mulga root and continued his journey to Darwin.