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quick carburetion fix

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When I turn the key to the 'on' position and the pump starts ticking, it doesn't matter how long I sit there before starting the car, it never changes as far as ticking goes.
 
Ok Jay, there is a leak then, you just have not found it, that pump should stop when it gets up to operating pressure.

Now that said, it could be pumping nothing on the outbound side or getting nothing on the inbound side.

If it was me and it is not of course, I would first check all fuel filters if any?

Hmmm, maybe the pump is not pumping, hmmm, think it has a rubber diafram (sp) in side that actually does the pumping, is that correct Tony? If the diafram has a whole in it or the rubber? stop valves inside are not working properly it is not building pressure.

Confusing, ok, two opitions at this point as I see it.

1. No or very little fuel gets to pump so no output.

2. No fuel is going through the pump. PUMP BAD.

I think you said someplace that you disconnected pump from tank and fuel ran out of the line did you not? If so I am convienced that the pump is the problem.

Tony please jump right in here and show everyone how wrong I am, HEHE.

Really, I would pull the pump. Hope you have an extra around?
 
Ok, found my expanded view of orginial pump. If I was a betting man I would bet that the diaphragm has seperated from where it connects to the arm spindle that is driven from the point set. The click click click is the point set operating.

Pull the pump, open it up and check the diaphragm. Small crack in rubber where it meets the shaft would be a good guess.

Must also be a check valve of some sort to keep the pressure up, might be rubber or a metal ball against a seat, guess that could be stuck as well, but would bet on diaphragm.
 
Jaybird, I've been reading this thread with ever increasing interest ( and needless to say, shock and horror at the prospect of your driving anything but your MG )
Just two questions: When Emma was all well, was the fuel pump ticking all the time then as well?
And: What kind of fuel pump does Emma have?
I understand there are some non-original ones that don't stop ticking...
 
I should think the pump would keep up with the early deteration of the diaphragm and as it got worse fuel pressure would fall till their was none and the engine of course would quit. Hmmm, catistrophic event, all stop.

And yes I see there is something called a non-return inlet valve. Check that it is free and working as well.
 
If it's the SU pump it'll have an inlet and an outlet valve. Both are "flutter" or "diaphragm" valves with light springs behind and snap rings to keep 'em located. The main pump diaphragm is very rarely the failure point, tho I have seen them split. I did interpret one post she made as: the pump is putting out fuel, but not clear how it was checked. Banjo's "pinch the supply line" suggestion would be my best non-emperical test: the pump (when blocked off at the carb end) ~should~ build pressure quickly and slow the ticking or cease completely, as long as the diaphragm and valves are working correctly. If it continues to tick over at a rapid pace when shunted, the pump becomes tha "target of investigation." And it DOES sound as if there's a supply problem: Lack of fuel rather than too much.
 
The suspense is killing me . . . and I have never even owned an MGB! In the length of time this thread has been up, we could collectively have rebuilt both carbs, replaced the fuel pump and fuel lines, and retuned the carbs and ignition system. So, who is going to be the first to volunteer to drive/fly to St. Louis to solve this problem? /ubbthreads/images/graemlins/angel.gif
 
"When I turn the key to the 'on' position and the pump starts ticking, it doesn't matter how long I sit there before starting the car, it never changes as far as ticking goes."

Gota be the fuel pump, just has to be.
 
Yeah, this innernet thingie is both blessing and curse... had she been nearby I'd have done just that, Steve. Or made the swap to the twin SU's in an afternoon here at Chaos & Mayhem PTY., LTD.

With the appropriate beer ration, of course. /ubbthreads/images/graemlins/thirsty.gif /ubbthreads/images/graemlins/cheers.gif /ubbthreads/images/graemlins/hammer.gif
 
/ubbthreads/images/graemlins/savewave.gif
Well DR-E/JB, maybe the pump is just sucking air on the input side---Fwiw---Keoke
 
Hahahahahah, you don't supose she is out of gas?
 
That's a helluva thought.

Naahhhh.
 
That's a frightening thought!
When I got my TR4A, back in the early '70's, it had spent most of its life on Taiwan, being tended by Chinese mechanics. I worked for a week straightening the electrics out, put five gallons of gas in it, and had to leave for work.
The next morning, it wouldn't start. As I had been doing nothing but electrical to it, that's where I concentrated my efforts. Imagine my embarrassment when I found, about four hours later, that someone had siphoned all the gas out of it overnight.
Sometimes, you just don't see the forest for the trees.
Jeff /ubbthreads/images/graemlins/blush.gif
 
If the fuel pump never stops clicking you've got pressure problems...if it was trying to pressurize but couldn't because float was stuck, you'd have gas EVERYWHERE! It would be running out the carb onto the ground...so, I'd look at doing what Banjo said above - it won't change anything but you'll know your problem is from there towards the rear of the car....
 
Yup-yup: Isolate. Eliminate.

I hesitated to post the "...gas EVERYWHERE" comment 'cause I wasn't sure if it'd run out the front due to the increased angle on the throat... but if it'd filled the chambers, well... can you say "HYDRO-LOCK?"

Yikes.

Insufficient fuel supply.
 
You guys know we may never hear from JB again if the problem was an empty fuel tank.

And that would creat a real loss here on the board.
 
She'd fess up. She's tough enuff to take th' guff... 'specially comin' from GUYS.

But if that IS the cause, I'll chip in to get her a vanity plate fer Binabox when the time comes: "SNIFFN E" !!!
 
How about "GASLESS"
 
mehheh... or "FUELISH"
 
I'm betting its that little fuel line from the pump to the hard line...its gotta be either that or the pump diaphragm

...or she could be outa gas! (we need a 'snicker' happy face!)
 
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