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MG MGA - The engine started!! Now what?

Hi everyone,

I finally got the engine started for the first time in three years!

However, it immediately jumped to 3500 RPMs. I had white smoke come out of the exhaust, which is probably to be expected. The throttle arm was all the way down on the carbs, so that's not it.

Perhaps my carb jets are too open?

What procedure should I follow to get the engine humming?
R Stokes

The jets just provide fuel. Without air, they wouldn't make it run fast, just make the mixture richer. You must have too much air getting in somehow. I would check the actual throttle plates to make sure they are closing, not just the arms. Another possibility is that you have an air leak around the manifold or vacuum advance fitting. This combined with jets that are open too far might make it run fast.

Jeff Schultz

Hi Rob. Jets could be adjusted too rich, choke levers could be improperly adjusted, fast idle screw (on carburettor cam)could be out of adjustment, or idle screws on both carbs could be out of adjustment. Are both the throttle plates closing completely? is the throttle return spring in place? Are the 2 choke lever return springs on both carburettors in place? These things in addition to what was mentioned in previous post. At least your engine RUNS! Congratulations! Glenn
Glenn

Ok, it turns out that the throttle arm was misaligned and the rear carb throttle was part-way open while the front one was closed. I backed both screws out all of the way and re-aligned them, now it runs at 1000 RPM. Still seems a little high - shouldn't it die out with the throttle arm completely closed? Can this be a jet problem (I've backed them off two turns, but haven't adjusted the carbs in any other way yet)?

The two springs on the end of the throttle arm are both in place and working, but it appears that the throttle cable has a little copper sleeve on it near the mounting bracket that is falling out. This is jamming, and preventing the arm from returning fully. Not a problem yet (I haven't pulled the cable while the engine is running), but it will be once I want to drive it. Suggestions?

-Rich
R Stokes

More jiggling and the engine runs at about 800 RPM now with the arm completely closed and the air filters off. I suspect that with the further air restriction provided by the filters, it will probably run just about right.

R Stokes

Hi Rich,

You might want to check if there is any false air getting in. When the valves are closed completely, the engine should die out.

What are your shafts like? New? Is there any play?
Are the valves aligned?

Koen
Koen

Don't idle the engine too slowly if it has been reconditioned as the oil circulation will not be so good. 1000rpm is slow enough for the first 500 miles.
Iain MacKintosh

Rich,

I agree with the last comment. It's not my intention to get you to set it even slower as it is. But please make sure there is no false air, this will result in a lean mixture and a hotter burning mixture. ( bad for the valves etc )

Koen
Koen

This thread was discussed between 27/08/2005 and 29/08/2005

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