What kind of carb is this and how do I tune it?

[enkeivette]

It says edelbrock and weber on it. It's a squarebore, aftermarket I'm almost certain.

Problem is, it falls on its face at WOT, almost stalls out. You need to lay into the throttle slowly before you can go WOT.

I'd like to hook up my LM2, but I'm not so sure that it will work and not damage the 02 sensor since water blows out the exhaust. I fear I will come to know this carb as well as I know Holley carbs. Ug.

 

[mrvette]

BEST 4 bbl carb ever invented, bar NONE....a Edel version of a Carter AFB....

they run fine right out of the box, for any typical engine....there WERE strip kits readily available for them, I still have one today....

the only difference I recall is the accelerator pump for some reason is different between the older Carter versions, and the Edel types....

Easy to work on, will not leak, unlike a Qjet or a Holley....

 

[enkeivette]

Forgot to mention, I've already adjusted the idle mix screws at idle to provide the highest possible vacuum. I think they ended up being about 2 turns out.

I can get the motor to idle at 800rpm in the water, but it will stall with a fast stop. So I bumped it up to around 1,000rpm to prevent stalling. I guess since the jet is constantly spinning and attached there is more of a load.

Haven't had a chance to set the timing yet.

 

[enkeivette]

Water temp ranges from 140- 160 btw.

 

[mrvette]

AFAIK, O2 sensor will NOT WORK in a boat with water cooled exhaust....

even for EFI....

:flash:

 

[enkeivette]

BEST 4 bbl carb ever invented, bar NONE....a Edel version of a Carter AFB....

they run fine right out of the box, for any typical engine....there WERE strip kits readily available for them, I still have one today....

the only difference I recall is the accelerator pump for some reason is different between the older Carter versions, and the Edel types....

Easy to work on, will not leak, unlike a Qjet or a Holley....

So if it works so good, what's with the stumble? Are there other adjustments to make on this? Or do I need to go right in and change the jetting?

 

[big2bird]

Soak it in carb cleaner 24 hours, throw in a kit and go. Set the timing first. The jets are probably fine. Boats sit alot, and get gummed up/corroded.

 

[enkeivette]

Soak it in carb cleaner 24 hours, throw in a kit and go. Set the timing first. The jets are probably fine. Boats sit alot, and get gummed up/corroded.

The only carb cleaner I know of is the spray, is there something I can pour into a bucket?

 

[mrvette]

Soak it in carb cleaner 24 hours, throw in a kit and go. Set the timing first. The jets are probably fine. Boats sit alot, and get gummed up/corroded.

The only carb cleaner I know of is the spray, is there something I can pour into a bucket?

Yes, I have seen gallon cans in parts houses, but a couple spray cans will do fine...mostly even here in the east coast, just some WD40 on all the external linkages to make sure all the shit works good, like chokes, secondary air valves, etc...check that your dizzy weights are not frozen, that timing works well, that maybe electronic via a module on the stern, like a buddy's Chapparell we playing with for some years now...here in Florida, corrosion and water are a huge issue, boats suffer greatly under canvas or not, honestly they belong in a garage on the east coast, anyway....

you can take that top off the carb as it sets on the engine, and see what inside, no sweat, the thing is much simpler than any other carb I have ever messed with....

:smash:

 

[DeeVeeEight]

I had a similar problem with my Bayliner - I let it sit one winter without adding fuel stabilizer and it gummed up the carb - here is what my mechanic did - with the motor running at about 2000 + rpm he covered the carburetor with a rag to force the carb. to suck the dirt out - just short of stalling the motor. He did this several times then instructed me to take it out and run it good - which I did and have had no problems since - but I do add the fuel stabilizer without hesitation now.

 

[big2bird]

Soak it in carb cleaner 24 hours, throw in a kit and go. Set the timing first. The jets are probably fine. Boats sit alot, and get gummed up/corroded.

The only carb cleaner I know of is the spray, is there something I can pour into a bucket?

Yes, Chem tool makes it. I have 2 gallons in a 5 gallon bucket.
Unfortunately, it takes 24 hours to get the results the old stuff did in an hour.

 

[mrvette]

Soak it in carb cleaner 24 hours, throw in a kit and go. Set the timing first. The jets are probably fine. Boats sit alot, and get gummed up/corroded.

The only carb cleaner I know of is the spray, is there something I can pour into a bucket?

Yes, Chem tool makes it. I have 2 gallons in a 5 gallon bucket.
Unfortunately, it takes 24 hours to get the results the old stuff did in an hour.

Acetone and lacquer thinners....cheeper to boot, but once again, not as effective as they used to be....

:surrender:

 

[Garys 68]

I've rebuilt about 100 marine AFBs, Mercs webers, or edelbrocks.
You'll need a torx driver to get the top off, and that's about the only complex part on them.
Buy a rebuild kit, take it apart, spray carb cleaner through every orifice you can find (on the carb). Put it back together and it will run fine.

 

[enkeivette]

It's a 1405, manual choke. Looking for a rebuild kit now. I'll report back after it's rebuilt and I've had it WOT on the lake.

 

[MYBAD79]

get the manuals from Edelbrocks website. Great carbs but the 800cfm 1812 that I have now seems to be quiet huge for a 383.... the 350 ran great with the 600cfm 1405 model.

Anyways.... simple to work on. You might need a jet and metering rod kit. It's so easy that even I figured out how to adjust the thing :lol:

Find out what size jets and rods you got, numbers are stamped on the parts. If they're the stock size it most likely ok. If someone tried to "improve" things you might need different rods/jets.

open it first, check what's in there and see if it's dirty....

 

[enkeivette]

Well I rebuilt it and it runs nice and smooth now. Somehow there was sand in the fuel bowls. Haven't had a chance to put it in the water, but it revs up quick, no bog while running on the trailer, and there used to be.

Question about the carb. On the secondary side, there are the throttle blades underneath, then the choke on top, and in the middle there is another set of throttle blades that pivot and are weighted, but don't attach to anything. They just rock back and forth. Why are these in there and how do they open at WOT?

 

[mrvette]

Well I rebuilt it and it runs nice and smooth now. Somehow there was sand in the fuel bowls. Haven't had a chance to put it in the water, but it revs up quick, no bog while running on the trailer, and there used to be.

Question about the carb. On the secondary side, there are the throttle blades underneath, then the choke on top, and in the middle there is another set of throttle blades that pivot and are weighted, but don't attach to anything. They just rock back and forth. Why are these in there and how do they open at WOT?

The choke on top is on the front holes, and has a little catch mechanism that when cold will stop the secondary weighted air valve from opening....the secondaries/Rear bores.. have just two flappers that I have ever seen....

when it's all warm and cozy the little lever from the primary choke releases the weighted secondary to open.....

that weight thing is the same function as the spring on a Qjet secondary...but a superior design, as is the whole carb, really....

I know Lars will hate me for that comment, but that's life....

:gurney:

Oh, edit, I still have the opinion that for storage longer than a month or so, it's best to remove the carb off any boat, seal the open mani, and stick it aside in the garage, after draining the gas on the weed patch....

yet another reason down the list for going FI on my boat, years ago....

 

[big2bird]

that weight thing is the same function as the spring on a Qjet secondary...but a superior design, as is the whole carb, really....

I know Lars will hate me for that comment, but that's life....

:gurney:

GM stopped using that design in 1966, and never looked back. It MAY be simpler, but far from a great carb.
Now if Edelbrock made QJets, they could sell the hell out of them.

 

[mrvette]

that weight thing is the same function as the spring on a Qjet secondary...but a superior design, as is the whole carb, really....

I know Lars will hate me for that comment, but that's life....

:gurney:

GM stopped using that design in 1966, and never looked back. It MAY be simpler, but far from a great carb.
Now if Edelbrock made QJets, they could sell the hell out of them.

With the 'strip kits' Carter made available, it was pretty easy to change jets, rods, pumps, whatever to make the things run good, to whatever state of tune floated your boat....try getting a BRASS float for a QJ, it better be Carter made, I not seen one in ages....but that CARTER QJ on the camper project has a BRASS FLOAT....

can anyone get a 'strip kit' for any QJ?? I never seen one....:hissyfit::gurney:

 

[Garys 68]

The secondary counter weighted butterflies are there to increase the air velocity when you initially open the mechanical secondaries. This provides fuel through a separate circuit from the main secondary jets when the butterflies are first opened. Once the air really starts moving through the secondary throat, that causes the counterweighted butterflies to open and the secondary jets take over.