Major carb overflow

Natenate4s · Post by **Natenate4s** » Mon Jun 08, 2015 8:22 pm

Just a little update. I adjusted the float levels. I think I went the wrong direction last time. I lubricated the needle valves. It's not overflowing! Woohoo! I have some new floats coming, and I'm going to buy some new needle valves then put it all in.

msampsel · Post by **msampsel** » Mon Jun 08, 2015 9:37 pm

Natenate4s wrote:Just a little update. I adjusted the float levels. I think I went the wrong direction last time. I lubricated the needle valves. It's not overflowing! Woohoo! I have some new floats coming, and I'm going to buy some new needle valves then put it all in.

Glad to find out progress is happening ...

Natenate4s · Post by **Natenate4s** » Sat Jul 04, 2015 1:49 pm

I replaced the needle valves and one float. Still waiting for the other float to arrive. Well I thought it stopped overflowing, then it just started doing it again. I've re routed my fuel line as you can see in the pic. to stop any vapor locking since I was fuel starved before this overflow issue. Can this be the problem?

Post by **Linda** » Sat Jul 04, 2015 1:53 pm

Not sure if the little gaskets get messed up after replacing the fuel valves. Maybe too the valve needs to be sprayed even though it is new.

Linda

keith0alan · Post by **keith0alan** » Sat Jul 04, 2015 2:07 pm

Did you replace the float bowl gaskets? Whose float valves did you use? Stock fuel pump? The SU carbs want about 3 PSI fuel pressure. If you are running 6 they will tend to not seal.

Natenate4s · Post by **Natenate4s** » Sat Jul 04, 2015 3:14 pm

I have replaced the float bowl gaskets. Twice now. Last week gas was shooting out from one of the gaskets even though the screws were tight. I didn't spray the new needle valves. But they were moving nice and easy when I put them in. I'm using parts I bought from a carb kit I bought on eBay. I bought the floats on eBay as well. Btw I just got the other float in the mail! Lol. At least that's a little uplifting.

Natenate4s · Post by **Natenate4s** » Sat Jul 04, 2015 3:19 pm

Here's the electric fuel pump that was installed and the floats I'm using. The fuel pump is 2-3.5 psi according to the website.

Post by **spl310** » Sat Jul 04, 2015 3:22 pm

Good float, what PSI is that pump rated at?

Natenate4s · Post by **Natenate4s** » Sat Jul 04, 2015 3:24 pm

Here's the carb kit I bought.

msampsel · Post by **msampsel** » Sat Jul 04, 2015 3:46 pm

Natenate4s wrote:I replaced the needle valves and one float. Still waiting for the other float to arrive. Well I thought it stopped overflowing, then it just started doing it again. I've re routed my fuel line as you can see in the pic. to stop any vapor locking since I was fuel starved before this overflow issue. Can this be the problem?

I assume the new float and needle carb is the one which started doing it again.
One carb still has the old floats .... right? Are you just letting the electric pump run
without the car running and then it overflows?

keith0alan · Post by **keith0alan** » Sat Jul 04, 2015 4:41 pm

Those are the good floats. If you are loosing gas around the float bowl lid rather than the overflow then there is a problem with the gasket or lid. Take the lid off and make sure it is flat. If it has been bent from over tightening or other abuse it will be hard to seal. Check your new float valves with the old ones. Some aftermarket ones sit low. If you bend the tab enough to get the float level right then the tab is pushing to the side on the float valve. Where the tab touches the valve should be parallel with the face of the lid. If it sits low then add a few extra washers under the valve when you install it.

Natenate4s · Post by **Natenate4s** » Sat Jul 04, 2015 6:10 pm

Both have the new floats now. The one time the gas flowed out the side was when I just had the pump running and not the engine. All other times it didn't leak when I just had the pump on. It hasn't leaked from there since. I switched the gasket, but the old gasket was practically brand new. I say less than 50 starts. All the other times it's been overflowing through the overflow. I didn't think about adding an extra washer so I'll try that. The inconsistency is strange to me. Just can't figure out why it overflows sometimes, and not at other times.

Natenate4s · Post by **Natenate4s** » Sat Jul 04, 2015 6:23 pm

I also put in some carb cleaner and lead substitute today. Btw the old needle valve were exactly the same as new new ones I put in.

keith0alan · Post by **keith0alan** » Sat Jul 04, 2015 9:21 pm

Fuel filter? When you take the cover off and lift the float out is there crud in the bottom of the float bowl? A bit of dirt flowing with the gas will stick the float open until it flushes through.

Natenate4s · Post by **Natenate4s** » Sat Jul 04, 2015 11:33 pm

Yeah there has been crud at the bottom of the float bowls. It's a new fuel filter.

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