View Full Version : TR4/4A Fuel pouring out of float bowl

01-17-2015, 02:14 PM
I was driving back from breakfast this morning and all of a sudden my gas gauge started really dropping. As I have had "issues' with the voltage stabilizer in the past, I didn't pay a lot of attention to this, figuring I would check it when I got home. Boy was I wrong.
After I parked the car, opened the hood (bonnet for those particular folks), I saw gas shooting out of the left hand side of the float bowl. I hit it a few times, didn't stop. I then decided to clean it, took it off, cleaned it and replaced the float needle and housing with a new spare that I had. Started the car again, gave it a few minutes and gas still rushed out.

Float moves up and down fine, and if I gently push the float tang on the top, the needle moves up and down.

Any other ideas?


Geo Hahn
01-17-2015, 02:38 PM
Off hand there would seem to be only three elements involved:

Float (is it sunk?)
Valve (is it stuck?)
Tang (does it need adjustment?)

I would remove and shake the float to make sure it is not holding fuel (would make it float to low).

Sounds like you have confirmed operation of the valve and even replaced with new.

If the first two are okay I'd review the tang adjustment.

After that I'm out of ideas unless you're running an electric pump.

01-17-2015, 02:41 PM
The valve is not working. i would again remove the lid and check the function of the valve by blowing (by mouth) through the inlet side and see if you can shut off the flow by rising the fork above the float. Also make sure that the float itself does not have any fluid inside. Also again remove the valve and make sure the channel is open.
It has to be either the valve, the fork adjustment or the float.

01-17-2015, 03:00 PM
That's why I posted this - I've run out of ideas as well! The float comes all the way to the top. I adjusted the tang just now to engage sooner, but the same result. I even boiled the top in hot water after spritzing the inlet tube with carb cleaner in case there was something blocking it.

So...The only thing I can think of is to adjust the tang to engage even sooner. I'll post tjose results.

01-17-2015, 03:38 PM
Stupid question I'm sure - but - Other than pointed end down. Is there any particular direction the float valve itself should be pointed?

01-17-2015, 03:57 PM
Well let's just say that the needle portion of the valve has a pointed end that goes inside the housing of the valve. The end of the valve the rests against the float shut off tang has a flat surface. As a warning -- just because something is new does not mean that it will work. Which is why I previously recommended that you test the function of the valve by blowing through the inlet pipe and being able to get it to shut off.
Good luck.

01-17-2015, 04:05 PM
Well - there is an advantage to having two carburetors... I checked the float chamber in the other one and after all the cleaning - I installed the float valve bassackwards. With the pointy end up - everything closes fine and no gas leaks.

The help here is tremendous - now if I could just geet out of my own way sometimes - the jobs might go faster!

Geo Hahn
01-17-2015, 04:08 PM
Edit: Glad you found it.

No particular orientation to that valve other than, as you say, pointy bit down. Be sure it works very freely, sometimes a new valve has something on it that causes it to stick.

So...The only thing I can think of is to adjust the tang to engage even sooner...

You are aware there is specified adjustment here - procedure involves using a purpose-made shaft or a drill bit of the specified size. All in the manual so I won't try to quote/misquote from memory.

01-17-2015, 04:34 PM
Well - there is an advantage to having two carburators--
Yes it gives us the advantage of doing two things wrong instead of just one.
Glad you got it worked out. So the original valve must have been the problem. Sometimes it is just a piece of debris caught in the valve. So once that is removed the valve will work as designed.

01-18-2015, 04:24 AM
when it happened to me the problem was debris in the gas; maybe a bad filter, but I was shocked how the smallest obstruction of the float needle can cause that kind of problem.

01-19-2015, 09:46 PM
After it happened to me ONCE I put an after market fuel filter in the system between the fuel pump and the carbs. It has not happened again.