MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - HIF question pt.2

Hello all:

A while back I had posted an issue with installing early flat throttle disks to replace the ones with the pop-it springs. Yes, in fact there is about a 1/4" brass tube that sticks up preventing the new disks from fulling closing. Solution was to file a small notch out of the bottom of the new throttle disks, allowing them to fully close. Now onto my current issue/question:

I have been unable to properly tune them. I set them to factory specs as a starting point. Once I can get the car warmed up, I commence tuning. Idle and balance are set, then the mixture. Problem is I cannot stop the carbs, specifically the front one from backfiring when adding any throttle. Even when it appears that I have finally solved the issue, I'll go out for a test drive - fine for a while, then backfiring commences when I add throttle from a stop. I have been completely perplexed by this issue. Usually backfiring from the carbs means too lean, so I go the other way - extreme to extreme with no luck as of yet. Looking for any guidence.

Shawn
Shawn Herndon

Shawn - Have you checked the oil level in the dampers since you did all the work on your carbs? A low oil level in one or both dampers will cause the problem you describe. Cheers - Dave
David DuBois

Dave:

Oil level kept topped off.

Shawn
Shawn Herndon

Try putting air filters back on. I had similar problem with a 72B roadster, same carbs, til I put the filters back on.
Tom Trepac

Did you recheck the balance just off idle as well as at idle?
Paul Hunt 2

This thread was discussed between 19/11/2006 and 20/11/2006

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.