MC 2150 carb venturi problem

[escobar]

AMC 258 i6 / 4.2l 76' CJ5 with a MC 2150 carb.

I noticed that one of the venturis is dripping a lot of gas down the intake for about 3 minutes- flooding my engine after shut down, making it hard to restart.

Float valve? Something else? Haven't gotten into it yet. The fuel pump is mechanical and doesn't have a return.

Never been into a 2150 before, but only 1 venturi is doing this. The idle circuit looks like its squirting gas for a little while too.

I did pull the gas line off the carb and it had quite a bit of pressure- not sure how much is normal on an amc but didn't think it should be that much.

Any feedback guys? Thank you.

 

[elwood blues]

It just jounds like it's time for a rebuild and a good overnight soak in carb cleaner

 

[dalefan88]

It just jounds like it's time for a rebuild and a good overnight soak in carb cleaner

i agree

 

[elwood blues]

I'm pretty sure this is the correct rebuild kit for a 2150

Store Locator | NAPA Online

 

[escobar]

Well I'm going to end up with a rebuild most likely. The shame is that it was done around last year ( so the p.o. Says)

Just looking for input on what would make only 1 venturi leak like that.

 

[elwood blues]

Well I'm going to end up with a rebuild most likely. The shame is that it was done around last year ( so the p.o. Says)

Just looking for input on what would make only 1 venturi leak like that.

plugged full of who knows what :dunno:

 

[Rescue Diver]

It does sound like your needle and seats may be ready to be replaced, but really high fuel pressure can push gas past good ones. I take it you're running a stock mechanical pump? I've never heard of a stock pump putting out too much pressure for a regular carb? Keep in mind that the pump is driven by a lobe on your cam, so depending on where your motor stops rotating in its cycle at shutoff, some times it'll spray a lot of gas when you unhook the line, while other times it won't.

As for just one venturi dripping, maybe there's a slight tilt to your engine due to motor mounts, suspension, or parking on an unlevel surface and the one that's dripping is just barely lower than the other so fuel reached it first? Or you could have slight clogging of the side that isn't dripping, but if your jeep runs fine otherwise, I doubt that.

Still, a nice overhaul of the carb is always a good thing. They're really easy to rebuild and the kits are under $20. Better safe than sorry.

 

[escobar]

Well, I took it all apart and- the p.o. wasn't kidding about the rebuild. Its all new in there. The venturi assembly wasn't quite seated right though. Still doesn't explain the flooding.

Now it runs and restarts fine- weird but good.

Anyone know the zero setting for the idler screws? I've got her tuned alright but just curious if its 1 1/2 turns out or 2 1/2

 

[Rescue Diver]

Well, I took it all apart and- the p.o. wasn't kidding about the rebuild. Its all new in there. The venturi assembly wasn't quite seated right though. Still doesn't explain the flooding.

Now it runs and restarts fine- weird but good.

Anyone know the zero setting for the idler screws? I've got her tuned alright but just curious if its 1 1/2 turns out or 2 1/2

I believe it's one and a half turns out initially, then with a vaccum gauge turn them equally in or out a half turn until you read maximum vaccum.

 

[escobar]

Ok good thank you.

 

[1960WillysCJ5]

Sounds like float level, and/or a miniscule piece of that was keeping the inlet valve from closing all the way. You may have dislodged whatever it was just by opening the carb up to look in it.