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MGB '71 MGB charcoal filter problem

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GaryBeu

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Hi Gals and Guys...I'm at the point of first attempt at starting this car in 18 years! Fuel flows just fine and POURS out the large hose on the bottom of the charcoal canister. I don't understand that system so what's up?? Can I connect the two hard lines that run into it with fuel hose and just bypass the canister? Thanks for any help.
 
YIKES!!

First thing I'd be doin' is a carb rebuild. Viton tipped float needle and a good goin' thru of the ports and passages in the body of the beast.
 
Thanks a lot guys...I REALLY didn't want to hear about rebuilding carbs since I'm not much of a mechanic. Guess I'll have to learn, huh? Is there any short explainatiion of why the fuel runs out that large hose? Just curious. :smile:
 
Float not working correctly could be one reason.
 
Short answer: "CRUD" in the float needle.

Long answer: If the float needle/seat is compromised, it's likely the rest of the carb has build-up as well.

The unit isn't nearly as complex as it may seem. A good carb kit and some patience will have it as good as new. It ain't magic! If you can fix a leaky faucet it'll be a learning experience. It's hung out there and easy to get to. No intimidation!

Chase Tony's link about the canister after you've been thru the rebuild.

Here's intimidation for ya:
 
Quick check, assuming the carbs are SU and not something else, would be the floats. If they're HS's, you might get away with checking them on the vehicle, but you'd really be better off to take them out, slap them on your favorite bench, and go through them.

They're not really complex devices and actually, except for removal and installation, working on SU's is kind of therapeutic. Now, a Quadrajet, that's a different story...

18 years of non-operation really demands some pre-ignition maintenance or you might end up running for the marshmallows and coat hangers while waiting for the fire department to arrive.

Points, plugs, carbs, heater control valve ( right Doc?), brake and clutch "reservoirs", handbrake,radiator, weird looking, taped up wiring...all of these (and more)need to be scrutinized before you turn the switch the first time. You'll be much happier that way.
 
:lol:

All true and correct! The heater control is a source of consternation due to its proclivity to LEAK and drip onto the dizzy, offering a great ground path for the HV.

Likely not the actual issue in this case but another niggling little detail to pay attention to!
 
Yeah.I was thinking more of the inevitable discouragement that occurs when he corrects the float problem and the thing still won't start. Might as well eliminate the possibility before it rears its ugly little, corroded head :smile:)

BTW, Doc, what is that in the photo? I can't make out enough to ID. It looks like some sort of V-n engine.
 
Point taken. :savewave:
 
Sounds like something I can do...Thanks. I still don't understand why a messed up couple of carbs would cause fuel to come out the canister hose! :smile:
 
If the floats are stuck open, gas goes through the overflow tubes, and everywhere else, trying to escape its confinement. The fuel pump just keeps pumping. It can be a mess. I've had it happen. I can't remember exactly how the evaporative circuit goes, but I do know it's hooked into the carbs, at least it is on my 1974 GT
 
Thanks...I'll order a carb rebuild kit!!
 
You might want to disassemble and clean everything before you order, so you can determine if you need parts not included in a rebuild kit. Then, if it were me, I'd call Joe Curto, or someone like him to make sure I get the correct parts for your particular carbs.Just a thought.
 
A well thought thought, actually. Some "kits" come with less than what's needed.
 
Thanks...I'll do that. So who's Joe Curto?
 
In old country, I have good teacher of maintenances. :smile:)

Joe Curto specializes in SU parts ( Zenith-Stromberg, as well, I think)

He'll turn up on Google.
 
BTW Doc...what is the dizzy and the HV that the heater may leak onto??
 
Another thing you can do is buy a couple of cans of carb cleaner & spray off the outsides to include all the linkage......then spray out the insides real good....let it dry & try to start it again....but, don't let it run long enough to dump fuel in the cannister.

Turn the ignition on & listen for the fuel pump's "click-click".....it should stop within half a minute or so if it can pressurize the system....if it never stops clicking, turn the key off.

Let us know `what happens.
 
Thanks Boneidle
 
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