VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 RJH08 Carb Flooding

I'm having a problem with my carb flooding. It is an RJH08 carter. I can get out and drive and it works great, but after driving for a while it floods and shuts down. Then all I get is fuel pouring out of my air filter when I try to start it up. I have tried tapping on it incase its the float sticking. But this does not do any thing. I can let it set overnight and it will crank fine the next morning. I put a kit in it about a month ago and this did not stop the problem. Any ideas would be appreciated.

Are you sure the air passage to the float bowl is clear?

Yes as far as I cn tell it is clear. I'm going to pull it off in the morning and check it all out again.

This has been an ongoing problem with this carb since I bought the car. Not very reliable.

Most often there are two things that will usually cause that problem.....the needle and seat or a sinking float. If you put a new kit in the carburetor then the needle probably has a Viton tip. Remove the needle and seat and replace the assembly with a metal needle and a matching seat.

Also, remove your float and shake it. If the float has liquid inside then that will also cause your flooding problem.

Thanks Dog. I checked my float it seems to be dry. Submersed it in hot water and no bubbles. My needle does have the black tip, which I suppose is the viton tip. I'm looking for one at this time. I had this problem before I put the kit in it though.

Dog do the FS carb kits have metal needles

The one I got from the FS had the viton needle. I found the old one and put it back in. Cleaned every thing up and put back on. Running pretty good right now. But now for the dreaded road test. Oh,by the way, never throw any thing away...

Do you have a filter in the line near the carburetor?

There are only a few reasons that a carb will flood. If the needle and seat are not sealing. A new (either with viton tip or all metal) and/or clean set should seal. If the float is set correctly (3/4") and does not have any holes then it should do its job. If any trash gets between needle and seat then they will not seal. If the bowl vent passage is plugged the carb will flood. If the seat gasket is not sealing or if there is a hole in the casting you can have flooding.

The only other possible problem I can think of is too high fuel pressure. That is regulated by the springs in the fuel pump. If too stiff then you can have too much pressure.

Mychevy: Okay, let us know how the road test works out.

Was your old needle a metal needle or a Viton tipped needle?

Andys29: Yes, the kits from the Filling Station have the Viton tipped needles as do most, if not all, of the reproduction kits that are purchased today. The new old stock Carter kits have the metal needles but those kits are hard to locate and are expensive when found. The Viton tipped needles tend to deform in today's gasoline which causes flooding. Because of the flooding problems caused by Viton needles I refuse to use a Viton needle in any carburetor that I rebuild for a customer.

My old needle is a metal one. I put it back in and will give it a drive tomorrow.
No I do not have a fuel filter. Where do you recommend putting it. I tried the one from napa that I put in the glass bowl of my fuel pump and it did not work. The rubber on it actually plugged off the output to my pump. My pump does have the brass screen in it and I rebuilt the pump a while back with a kit from FS. How much pressure should I have coming from my pump?

I put an inline fule filter after the gas tank and out of sight. It stoped my carb from flooding. You might soak your carb in a vat of carb cleaner as well to get rid of trash that can hold the needle valve open.

A filter is an excellent idea and I will see if I can hide it some where under the frame. Good idea. Thanks

RJ,
I also used laping compound on the needle and seat to remove any dents or scraches. Be sure to clean the carb extra good after using laping compound.

As for filter I bought the FS-235 from the filling station and used on the fuel pump glass bowl

I have worked on some old tractors lately with updraft carbs and had flooding problems, I sanded the edges of the needle a little and that fixed it, needle must have been binding.

I routinely buff the outside of needles particularly the edges. It is to remove the invisible layer of gum/varnish that forms from modern gasoline nearly instantly. I also aggressively clean the insides of the seat.

I had a problem with rebuilt updraft carburetors that were test run and then stored upside down. Some of the needles stuck in the seats and would not fill with gas when installed. Tapping with a screwdriver handle most often got them working again. After several incidents I finally figured out that it was the gums/varnish that was gluing the needle to the seat. I checked the parts with magnifying glass but could not see anything or feel anything on the parts. But if put back on the shelf, then next time they were installed they would do the same thing again. If I cleaned aggressively with towel and good solvent and stored right side up I don't have the problem.

The major difference between the Viton tipped needles and the metal ones is weight. It takes much less gum to stick them and more giggling to unstick them. That is the reason the the Dog does not like them even if he does not believe it. I have run several carbs with the Viton needles without any major problems. They do have a benefit if small particles get in the seat area. The softer Viton tip will seal when the metal will not.

Thanks Chip I will check the needle and seat for gum. I'm going to install a filter today and take her for a ride.

Concerning the Viton tipped needles, based on my experience with this type of needle, here is where the Chipper and I disagree. Decades ago when I first started rebuilding Chevrolet carburetors, the repair kits that I ordered contained metal needles as standard equipment. With the metal needles I never had complaints about flooding. Then, as the metal needles were phased out by the suppliers and they were replaced with Viton tipped needles, from time to time I would receive a complaint about a flooding issue. As gasoline became worse the flooding problem started to arise more often.

Over about a two year period as carburetors would come in for restoration, myself and my customers did testing of the Viton tipped needles. The testing was done in all parts of the country and with different brands of gasolines. Ten Chevrolet carburetors, both Carter updrafts and Carter W1 carburetors were completely rebuilt to brand new specifications and Viton tipped needles were installed in all of the carburetors. All ten carburetors experienced flooding problems and all were attributed to the Viton needles! Three or four carburetors flooded almost immediately and the other carburetors flooded after a small period of time after the vehicle was driven on the road.

The Viton needles were returned for inspection. Under close examination with a magnifying glass the majority of the Viton needles had deformed rubber tips from the gasoline....and some of the rubber tips were grooved on one side of the tip as well. These are the reasons that I don't like and will not use a Viton needle! On each of the 10 carburetors the Viton needle was replaced with a new metal needle and matching seat that I supplied and the flooding issue was resolved.

This test was performed about four years ago and since then all of the rebuilt carburetors have contained metal needles and from the input that I have received from some of my customers, none that I am aware of have had flooding problems other than the occasional partical of dirt from the gas tank. Also, over the years I have received numerous phone calls from Chevy dudes that have rebuilt their own carburetors and installed Viton needles, and they have experienced the flooding problems with the Viton needles. Those that had metal needles available installed them in their carburetors and that eliminated the flooding issue. I will not, under any circumstances, install a Viton needle in any rebuilt carburetor for a customer because I feel that my customers deserve the best quality parts possible.

Chipper Dipper run tests his carburetors as he explained in the above posting and due to the gasoline residue that remains in the carburetors he has experienced sticking needles while the carburetors are in storage. His observation is absolutely correct! Since I am well aware of the gasoline residue issue on the needles, and because many of the carburetors that I restore for customers are not installed on the vehicle for months or for several years while the vehicle is being restored, none of the carburetors that I restore are run tested prior to shipping to avoid the residue/storage problem. Therefore, in the carburetors that I restored during the test, the gasoline residue causing the Viton needles to stick while in storage is a non-issue.

When I had trouble with my 1931 flooding I replaced the needle and seat with a Grose Jet which I believe uses 2 steel balls. It has been 30 years with no trouble. I do not know if they are still available. Anybody know?

From what I have seen on the Internet it looks like the Grose Jet is still available.

Thanks for your input Dog. I have put my old metal needle back in and did a test drive today. So far so good. I drove her for a good two hours and no flooding. I suspect I may have an issue with my gas tank sending specks of rust to my carb.I put a filter in the line from the pump to the carb to help matters. I guess my next major deal will be to pull the gas tank and do some work on it.
I can't wait.
Any way thanks for your comments on this issue.

After a test run I now blow the needle/seat dry. That and storing carbs upright has solved the problems I had with carbs I use on my cars and trucks. I have also not had customer complaints of flooding since I began using that procedure a number of years ago unless they also find particles in the bowl. I was really surprised that the small amount of gas remaining on the needle/seat was enough to stick them together. Guess that is part of the Gremlins routine.