Technical Problem with Edelbrock 1406 carb.

Well... these are just not my days for auto's.

So after not being able to find ANYWHERE within 60-70 miles to buy floats and gaskets, without them being ordered, someone that rebuilds carbs out of his house called me. (Small parts store owner called him)

So great, price was even ok. So my wife gets home from work and we proceed to go get the Edelbrock parts in our mini van. Get to the end of the street and the damn fuel pump goes out on IT.

Wow... not my week for auto's/trucks.

So, I got a neighbour to take me to get the parts, had a hard time getting the replacement float adjusted, thought I had it. Put it together and had a hard time getting it to start. Finally did and it runs kinda poorly. runs rough and smells of gas at the tail pipes.

At least no leaking and the gas does not drain back towards the fuel tank.

Guess I'll drive my wife to her NEW job tomorrow and I'll get a new fuel pump for the van. Once the van is running again, I'll pull the top of the truck carb and give the float adjustments another go at it.

John

 

OK... running fair now but massive fuel boiling. Before on really, really hot days I would hear some boiling in the bowls, but now (after float and gaskets replacement) there is boiling in the carb and boiling in the site glass/filter. I mean extreme boiling.

I have never seen it boiling in the site glass itself before. Site glass is about 10" from the carb fuel port.

I put the 1" spacer on it that the Summit tech recommended and haven't had much of an issue with it before now.

Any ideas guys?

Thanks,
John

PS - If the floats were not adjusted perfectly, would that cause heavy boiling? I think I have both of them at a bit less than 7/16"

 

Is there any chance there's vacuum pulling on the fuel line?
Lower pressure would greatly lower the boiling point.

 

How would I know this? Gauge shows about 4 - 4.5 PSI go to the pump. The only two lines are the distributor advance and brake booster line.

 

Heat,
check the fuel line , fuel tank to make sure they are at least an inch from the exhaust and the fuel line is not touching the engine, except for the carburetor. The high fuel level will not cause the boiling, it will only make it worse.
Insulate the fuel line where you can. try a few clothespins on the fuel line near the carb, don't laugh, they work...
How old is the fuel ?

 

Thanks for the response.

Fuel is fresh.

Fuel lines are in their original position and fuel line at/near carb is already routed away from carb and tied up with zip ties. I have not tried any insulation. What should i use for that?

Thanks,
J

 

a few pictures of your setup would help. How fast does it start boiling? Nearly immediately or after 30min, or???? No matter what, I would get rid of that glass filter. If it cracks against the block from vibration, you could get a big fire real quick. Use a 3/8" or 5/16" clear plastic filter, You can get them for $1ea at any swap meet or a few bucks at the parts store. I always grab a few whenever I'm at the swap meet so I have extras. I have seen those glass filters actually cause bubbling from bad seals and vibration that looks like bubbling, but is just agitation of air in the lines. The plastic filters have finer mesh filter material that help dampen that agitation versus the bug screen that the glass filters have.

If you have access to one of those infrared non-contact laser thermometers, it would be a good practice to do some tests taking readings of the carb temp at different time intervals to see just how hot it is really getting if it is. My guess is what you are seeing in the filter is trapped air in the fuel line bouncing around.

 

That's what the cowboy said when his horse died! (Just messin' wit ya.) lol

 

I'll put some pics up later today. I'm working on new fuel pump for my van right now and have to go.

Thank you,
John

 

Just throwing my two cents worth in. Maybe a crack in the suction side of the fuel pump and sucking in a little air and its mixing in with the fuel and looking like its boiling. Its a long shot cause I've seen cars totally disabled with a cracked rubber hose going from hard line to rubber ,to fuel pump. Lots of good info so far. I like the Infra red temp gun and making several temp checks along the way. This guy lives in Florida and I assume its pretty warm there already. A little percolating might be normal anyway. It is for me here in Vegas. I've got two Edelrbrocks on 350 chevies and they both seem to have similar problems in the summer. Have to depress the throttle when warm to get them to fire off if after running in the heat. Try dropping the float a little more. see what happens.

 

OK John, dont want to split hairs and I'm not english major but when you say 4psi going to the pump. Does that mean the line coming off the pump to the carb? Or the line coming from the tank to the pump. The line coming from tank is the on going to the pump or the suction side and if you have 4 psi on the side that dose not compute. Should be a vacum signal on the suction side of the pump and say 4psi on the discharge side of the pump. If you had vacum on the line going from pump to the carb that would definitely lower the boiling point of gasoline and cause great amounts of boiling action.a And I dont think the car would even run let alone run well. Its the little thnigs in life that drive you crazy. PS is there an electric pump somewhere in the system prior to the mechanical pump. Just asking.That might get enough fuel to the carb through the misplumbed mechanical pump to keep it barely running. So many variables here without looking at the car itself. Also maybe installing a cheap elec fuel pump temporarly around the mechanical pump for shits and grins to see if that helps somehow. Also how hot is the engine running? Fuel getting supper heated while passing through the fuelpump? Radiator heat blowing back on to the fuel line. I've heard the clothes pin thing before and some swear it works but my sheets somehow don't smell nearly as fresh,lol. Good luck. I want to see this solved.