shaken and stirred

[Sopwith_Camel]

the engine shudders violently and back fires and dies

it seems to be about a hour after a new tank of gas
on hot days
it started mid august

I ve tried dry gas thinking water in the gas.
it might be electrical

after siting for 30 minutes it fires up and gose fine
so heat or time could be part of it

but it dose die at 50 mph and rolls to the side of the road
steve

 

[Billm]

Sounds like a fuel pump that is dieing or a pinched or clogged fuel line.
BillM

 

[vagt6]

I'll bet it's fuel pump "vacuum lock"!

Is your fuel cap vented? Try this: next time it dies, loosen the gas cap so it will let air in, then drive. It could be that simple (<span style="font-style: italic">if</span> you're lucky and the MG gods agree).

On my MKIII the fuel system MUST be vented, otherwise, as fuel slowly drains out of the tank while driving it creates a vacuum which will lock up the fuel pump. Engine dies of fuel starvation. After it stalls, if you take the gas cap off or loosen it, the car will start right up when this occurs.

Give it a shot. If venting the system works, then drill a very small hole in your gas cap so it won't happen again, or purchase a vented cap.

Don't ask me how I know this. Happened to me twice, once I had to have the car towed about 30 miles . . .

 

[Sopwith_Camel]

ok yes it is after a hour of hard driving each time. I did think of poping the gas cap this time but it died 400 yards later

it did seem to stay till the engine cooled a bit and the fuel pump too

hmm better order a fuel pump over the winter
steve

 

[Deleted member 8987]

Or a filter plugged (last tankfull from bottom of barrel?), ethanol eating rubber fuel lines, which are then collapsing?

 

[vagt6]

Steve do you have the OEM points-type fuel pump? You can test it for functionality, and also they can be rebuilt.

I installed a new Moss one recently, it's not a difficult job.

Is it ticking? If not, sometimes a nice rap on the side of the pump with a screwdriver handle will get it going long enough to get you home. Worked once for me.

Test it and let us know.

 

[Hairyone]

I had this on a hot engine with a mechanical fuel pump on 1275 engine (that sits under manifold). Pump got too hot & leaver stuck.

 

[Sopwith_Camel]

yes this is the moss one in the rear wheel well
yes its ticking this issue started on a hot drive on august 15th (mg car club rally)
I did pop the gas cap yesterday
maybe I am having the vacume issue that then over heats the pump?

steve

 

[vagt6]

First,let us know if venting the gas cap solves your problem.

This particular problem (e.g., vacuum lock) is a bugger because the only way you can test it is to go for a long-ish drive. Kinda like tempting fate, really.

Of course you could have both problems: vacuum lock AND a bad fuel pump. Let's not go there yet, though.

Let us know . . .

 

[nomad]

Very occasionlly, I think, you could blame those symtoms on a failing ignition coil. Easy to substitute if all else fails. I had one on a MGB that acted a lot like that.

Kurt.

 

[nomad]

If the problem is fuel it should be fairly easy to diagnose by hitting the ignition switch as soon as it dies and removeing a float cover or if you have a clear fuel strainer before the carbs it will be even easier!

Kurt.

 

[Guest]

I pull the line off and let the pump run if I suspect vapor lock. My "vapor lock" was a faulty new cap from VB.

 

[Sopwith_Camel]

its the fuel pump
it stalled so I poped the gas cap off and tryed running it and no change
so the fuel pump is slowly dieing
hopefully i can limp it home about a mile up hill
steve

 

[Sopwith_Camel]

solution !! I bought a Jag!

https://www.finn.no/finn/car/used/object?finnkode=30892457

in for a penny in for a pound

 

[BugeyeNJ58]

And we all know that Jaguars never have any mechanical/electrical issues?
Good Luck....great looking car.