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MG MGB Technical - Missing on right turn w HS's

I have a 79 B with twin HS4's. When I give it a lot of gas turning right at slow speeds the engine misses. This happens both in first and second gears. It is temporary and only happens at this speed and situation. Does anyone know what might be the cause of this intermittent problem?

Thanks,

Jim
JMcHugh

Sounds more electrical to me. If it was a pre R/B, I would say check that the steering UJ isn't fouling the dizzy leads. The engine will also twist with the torque in a low gear, which might pull an electrical connection or earth a lead, especially if the mounts are worn.
Allan Reeling

Found similar on my 70CB but turning left! was no 4 plug lead had worn through against the coupling nut! Replaced lead and rerouted it a bit so it clears and problem solved (I also sleeved it just it case it works round)
Bernie
B Anderson

Does the tach jump all over the place with the misfire? If so it is the ignition LT with a bad connection or shorting as Allan says. In the early days on my roadster I found the white going to the coil +ve way too long and wrapped round the column.

If the tach is steady then it is HT or fuel. RHD MGBs can get the HT leads rubbed through by the steering column UJ, whilst LHD don't do that it could still be loose HT connections.

As far as fuel goes it could be debris in the bottom of the float chamber moving about and blocking the jet pipe, more likely in HSs than HIF (don't know about Stromberg).
PaulH Solihull

Thanks for all the help. Turned out to be a loose wire which was rubbing against the block on the hard right turns. Taped it up and all seems well.

Thanks again,

Jim
JMcHugh

If fuel is low, say less than 1/2, then hard RH turns can cause air pickup, lots worse under power. This results in a miss a bit later, when the bubbles get to the carbs.
Also, if float levels are set low, you get starvation in turns. How bad and which way may depend on float bowl top orientation. Autocross & race cars frequently have the float bowl tops turned to non standard angles, which requires clamping the top with washers, rather than having the screws through the holes in the 3 ears.

FRM
FR Millmore

I am assuming that this is a LHD car, so the problems encountered with the steering column, on RHD cars, doesn't apply here. RAY
rjm RAY

This thread was discussed between 18/04/2012 and 19/04/2012

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