The Stovebolt Site Forums The Shop Area Engine Shop sediment bulb question

I currently have a 52 Chevy car with the original 216. I am planning to install a glass sediment bulb filter just before the carb. I would like to know if I will have to worry about the heat from the exhaust causing problems for me.

Thanks,
Kael

I have basically the same setup on my 235 in a 54 truck and have noted "heat soak" issues with the E10 blended fuel. Not so much with the filter itself, but in the steel fuel line where it passes between the thermostat housing and rounds the corner of the valve cover. The issue pops up after the hot engine is shut down and restarted after 10-15 minutes. The steel line temperature (at the corner) reaches 150 degrees and you have to deal with a classic "vapor lock" scenario. The engine will crank and run until the float bowl empties...then shuts down until the engine cools. Applying a wet rag to the line right at the corner of the valve cover will instantly restore fuel pressure.

The glass bowl filter is a solid unit and although I'd been warned about a potential fire hazard I fabricated my delivery system with no real issues until the blended fuel became the standard. I'd suggest you run your steel line up higher in front of the valve cover and then drop down to anchor your filter to the carbs. You may need to try to insulate or put a deflector shield (webshots) to divert heat after shutting the engine down.

Dave

put a couple wooden spring clothes pins on the line - heat sink - problem solved - take'em off when you're at the show

Bill

Here are a few pictures of the stock plumbing on a 1950, 216 with an AC sediment bowl filter. One version is with a Rochester ‘B’ and one version is with a Carter W-1. I’ve never had a problem with vapor lock and have driven it all summer in temps up to 100° and run only E10 here in northern Illinois. Now that’s not to say that you wouldn’t have a problem down in the heat of FLA, but this was the way they all came from the factory back then.
http://www.pbase.com/dennygraham/under_hood&page=2

Denny Graham
Sandwich, IL

Thanks for the quick replies and photos. I'm glad to see that my planned setup will work. The unit that I'll be using may require that I move the steel line higher as it is designed with the input port on the top of the housing rather than inline with the output port.
Kael

Am I correct to assume that the glass bowl should be nearly full of fuel at all times? With my engine running, my filter consistently has very little fuel in it. I can see fuel coming into the filter as the engine runs.

I have been able to let my engine idle for about 45 minutes without any problems. However, my problem arises when driving. I've been able to drive about 3 miles before the car dies. Prior to dying, the engine stumbles as if it isn't receiving fuel. After about 10 minutes I can restart it, it runs for about 150 yards and then dies again. If I let it sit for a few hours, the whole process starts over. I don't feel any excessive heat from the engine and the air temp has barely reached 70 degrees over the past few days.

Should I look to replacing the fuel pump or am I missing something else? I'm sure it should be a simple fix, I just am not sure if I'm looking in the wrong direction.

did it work without the filter? have you had the carb open lately? might be a fuel pump problem, or possibly a worn push rod for the pump - could also be an improperly set carb float, or maybe a missing carb isolator letting the carb get too hot? ... but the filter bowl doesn't need to show a lot of fuel at any time

Bill

Bill,
I haven't taken apart the carb yet. The car also has done this with an inline filter in the same location. It seemed as if it was caused by a dirty filter in the past which is why I chose to go with a sediment bulb as I can clean that easily. I was mainly concerned because the bulb drops almost 1 1/2 inches closer to the exhaust. The spacer for the carb is in place. Also, I can get it run slightly longer when it begins to stumble by adjusting the choke. This doesn't solve the problem, it just allows me an extra minute or so of run time.

Kael

Sounds like you may either be picking stuff up in your tank or you have a fuel line from the tank to the fuel pump bent or pinched. More then likely it is junk in the tank.

Really need to isolate the problem a bit. If you can get an electric fuel pump, try it and leave the manual pump out of the loop. If not then try to gravity feed fuel to the carb and filter and see how it runs out.

I agree with 61chevygal, something is preventing fuel from getting from the tank to the carb or the pump is not performing to specs. The first thing I jump on is the fuel filter. Second I'd check the tank/lines for gunk. Then the pump. Then the carb.

I'm currently in the process of installing an electric pump. I have a new rubber fuel line running from the tank to a clear inline filter in place just prior to the mechanical pump. New rubber line from the filter to the pump. The problem has remained.

Regarding gravity feeding the carb, I don't know of a safe location to mount a temporary tank so that I can drive the car to replicate the problem.

If nothing else, I've gotten good at pushing the car and won't need to get a membership to the gym.

I think the car hates me! I installed a brand new electric fuel pump. It was bought in November but never taken out of the box. I can feel and hear the pump running. I can see fuel getting drawn into the clear inline filter (the one in front of the pump). After the pump, I'm getting no additional fuel flow. I even disconnected the output hose from the pump and didn't even get a trickle of gas. I allowed the pump to run for almost 15 minutes in case in needed to get filled with fuel first.

Is my car destined to just sit and look nice?

Are you creating a vacuum in your tank? Pop the gas cap and then try.

Are you observing the right polarity on the pump wires? It's possible to get it running backwards if the wires are reversed, putting fuel back into the tank. Also, can you put a little air pressure into the tank filler and push fuel through the supply line? It's possible you've got a restriction at the fuel outlet from the tank.
Jerry

filter "in front" of the pump? meaning inlet to pump? get rid of it and try again

Bill

Yes I also installed a filter on the inlet side of the pump. Found out that the genius who assembled the filter did so incorrectly. It would allow fuel into it but not out. I'm now getting fuel through it, the electric pump, and into the carb. Now I can take the car for another drive to see if the original problem continues. If not, then I'll replace the mechanical pump. If the problem still presents itself with the electric pump in place, I'll have to ask for help again.

I do know that the bad filter wasn't the initial problem because I didn't have it in place with the mechanical pump.
Thanks,
Kael

The filter past the pump is not a bad idea, but the best place is between the tank and the pump, I actually like the idea of the inline filter best. Tractor supply sells a variety of these
strainer kits

these with the correct fittings could be mounted to the bottom of your fuel tank, then you could run you fuel line from this-
It would give you a vintage shut off valve(these have been available since the late 1920's) a filter and a sediment bowl- An it would be at the lowest point in you fuel system giving you the most sediment removal.

The filter does look nice just before the carb, but this would be the best place for it. I put type that has the filter element in the glass bowl, but will probably change for the strainer type under the tank.
You can take a bean can, and cut U notches on either side and then suspend it around the filter housing to protect it from flying stones. Bailing wire or coat hanger works the best- just remember to punch a water drain hole in it in case you drive in all weather.

the heat in the fuel problem is why many of the YF style carbs were invented and sold- to stop a condition called percolation. The close pin idea does work pretty well(I have heard it from more than one person)