Edelbrock 1409 hard start, flooding

[Duffie]

Hello,

Long time lurer here, registered because of a problem i have with my gasoline v8 350 with edelbrock 1409.

My engine is pretty hard to start. And after some troubleshooting ive narrowed it down to my card flooding the engine (i think).

After i stop the engine the carb pours fuel into the intake. See attached video.

My question is if anyone can help me with how to fix this? I am very inexperienced with carbs.

Thanks for all replies!

 

[floater212]

check floats and needle. seems to be stuck open. also check fuel pressure, it needs to be under 6.5 psi or it will cause flooding.

 

[dubs283]

After i stop the engine the carb pours fuel into the intake.

definite sign of debris in the float bowl causing needle to remain off seat and most likely other clogged passages

time to diassemble, clean, inspect and rebuild the carb

 

[nola mike]

definite sign of debris in the float bowl causing needle to remain off seat and most likely other clogged passages

time to diassemble, clean, inspect and rebuild the carb

I've had that problem on mine several times. First time was because (I think) too high pressure from my brand new Carter pump (8-9 psi). Other 2 times not sure. I think (at least on mine) that the float can get hung up on the bracket in there when you put the top back on. At minimum need to pull the top off, check float bowl for debris, needles/seats to make sure they're sealing, and float drop/level. Probably best to rebuild, but you aren't out much time if the above steps don't work

 

[Lou C]

Agreed in the second vid is the engine off? It’s REALLY flooding prob a piece of grit between the needle valve & the seat. A possible quick fix is to remove the carb and drain out all the gas & let it dry out to be safe. Then with the carb level blast a bit of compressed air thru the fuel inlet. Now put a piece of fuel hose on the fuel inlet and blow thru the hose with the carb upright. You should be able to blow thru the hose, Now invert the carb and try to blow they the hose, you should not be able to if the needle valves are sealing and the floats are not hung up. If this doesn’t work the carb needs to come apart needles & seats replaced and floats checked.

 

[nola mike]

Agreed in the second vid is the engine off? It’s REALLY flooding prob a piece of grit between the needle valve & the seat.

Looked like it was flooding pretty bad on both sides, which had me questioning if it was grit. Though if it was working before...

 

[Lou C]

I never had an Edelbrock but I heard that the floats can hang up. On my Quadrajet both times I had that problem it was the needle valve. Easy fix once you got the air horn off. I also had flooding similar with a Holley due to a piece of rubber from those fuel transfer tube o rings holding the needle valve open. Gas was just pouring out the vent! Scary!

 

[nola mike]

I never had an Edelbrock but I heard that the floats can hang up. On my Quadrajet both times I had that problem it was the needle valve. Easy fix once you got the air horn off. I also had flooding similar with a Holley due to a piece of rubber from those fuel transfer tube o rings holding the needle valve open. Gas was just pouring out the vent! Scary!

I hadn't heard that, but there ya go. Mine flooded enough that the engine hydrolocked (petrolocked?). Luckily I realized what was going on before too much cranking.

 

[Duffie]

Hello,

Thanks for all your answers. Really appreciated!

The engine is off in both videos. Just shut down.

About the carb, during last winter i sent it to a shop to get it refurbished. They tore it down, cleaned and rebuilt it. This is a reputable marine engine shop here in Norway, specializing on american engines. I sent it to be refurbished because the boat was hard to start, but had not discovered the flooding yet. The videos are taken during last summer, after the carbs had been refurbished.

After reading a fair bit about this on the net, im starting to wonder if my fuel pump may be acting up, so tomorrow i will go buy a gauge and figure out what my fuel pressure is at.

Is it correct that a failing fuel pump can up the pressure?

 

[Lou C]

Something about the floats contacting the side of the fuel bowl. Might have to check clearances carefully. All carbs have their quirks. Right now I’ve learned most of the Quadrajet ones but when they are clean and properly set up they are really good. We owned a ‘75 Olds with a 350 and a QJet for about 10 years and run on straight gas not e10 while we owned it the carb never needed a rebuild. Just had to clean the choke plate and linkage a few times. Ran like a freight train the whole time...

 

[Duffie]

Agreed in the second vid is the engine off? It’s REALLY flooding prob a piece of grit between the needle valve & the seat. A possible quick fix is to remove the carb and drain out all the gas & let it dry out to be safe. Then with the carb level blast a bit of compressed air thru the fuel inlet. Now put a piece of fuel hose on the fuel inlet and blow thru the hose with the carb upright. You should be able to blow thru the hose, Now invert the carb and try to blow they the hose, you should not be able to if the needle valves are sealing and the floats are not hung up. If this doesn’t work the carb needs to come apart needles & seats replaced and floats checked.

I just went out and tried this.

I was able to blow through the carb when the carb was levelled, once i flipped it over, i heard the floaters move, and i wasnt able to blow any air into it.

Am i correct to assume the floaters and needles are functioning as they should?

 

[Lou C]

That would suggest that the needle valves are holding. I’d try it several times to see if they hang up. If not I’d measure fuel pressure to make sure it’s not higher than specs. It’s possible for a fuel pump to deliver too much pressure in a carb application. Check what Edelbrock says but I think 5-7 psi. More than that you can have a problem.

 

[Lou C]

Also:
If it floods that bad with the engine off are you sure that the oil pressure safety switch & wiring are functioning correctly? An electric pump MUST SHUT OFF as soon as the ignition is turned off!
The electric pump must be wired correctly to an on/off oil pressure safety switch so if the engine stalls or you turn off the ignition the pump stops. When you first start it the pump is powered off a lead on the starter and when you release the key the oil pressure has increased to the point that the switch closes and then it powers the pump.
With a mechanical pump this is a non issue.

 

[Duffie]

Also:
If it floods that bad with the engine off are you sure that the oil pressure safety switch & wiring are functioning correctly? An electric pump MUST SHUT OFF as soon as the ignition is turned off!

Hi,

I have a mechanical fuel pump on the block, without a fuel pressure regulator.

 

[nola mike]

Also:
If it floods that bad with the engine off are you sure that the oil pressure safety switch & wiring are functioning correctly? An electric pump MUST SHUT OFF as soon as the ignition is turned off!

Hi,

I have a mechanical fuel pump on the block, without a fuel pressure regulator.

@Lou C , that was my thought. I can't think of a way to dump that much fuel with a mechanical pump.

 

[Lou C]

Well it might be a good idea to check the pressure on that pump; although there is still a chance that you have an intermittent float sticking issue.

 

[Lou C]

Agreed with the engine off it really can’t be the pump.