Welcome to our resource for MG Car Information.



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 MGA - some advice

Front two plug gaps close up completley. All plugs are long reach. the back two are fine. This started a couple of hundred miles ago. I have fitted short reach plugs to the front cylinders and all is well. No oil pressure problem, bearing or gudgion noise. I can only put it down to carbon build up. The car is my Riley with a hemi head and centre plugs.
Question. Can I safely scrape the carbon through the centre plug hole and rely on the carbon being blown out past the exhaust valves and not sticking a valve open ? ? All contrabutions greatfully received. Sean

Pulling the head on a Riley is not for the faint hearted !
S Sherry

I seem to recall that there used to be something you could squirt in to the sparkplug holes that would dissolve (or help dissolve) the carbon build up on the piston crowns.
It hopefully only works on carbon and not aluminium!
Colyn Firth

Wasn't there something in one of the threads in the last month or so when someone said to pour water into the carb throats at about 3000rpm.

Steve Gyles

Water introduced slowly will do the trick.I usually fill a gallon jug and put a length of vacuum tubing in and let the engine suck the water while holding 2500-3000 RPM.
R J Brown

I have done it with water injesting it through the carburetor while engine is running. Run at least three quarts of water. Then follow it with a quart of the cheapest trans fluid available. Pour it in the carbs till the engine stops. Let set overnight and be certain to cover the exhaust with a heavy duty cloth when you start it up. It will blow black gook all along the driveway if not covered.
The water will turn to steam and will partially clen the carbon. following it will trans fluid will soften the balance. If your is that bad you may have to repeat.
One care that I did was my own Ford with a 360 cu.Inch motor. Carbon was breaking off and sounded like beer bottles clinking together. I did this and drove the car another 100,000 miles without further problems. That was caused by the cheap fuel available during our fuel crisis in 1973.

Works like a champ,and I second the rag on the exhaust when you start it up.
Mike Parker

you can spray water into your carb throats with the filters off using a spray bottle (like for windex) as well.

AJ Mail

I've used this method also. However, a thought to keep in mind: if there is any significant blowby, you'll have water and trans fluid in your oil. Best to do right before an oil change.
JM Morris

All these suggestions must be causing Percy to be turning in his grave. Give him a rest and take the head off!!!..............Mike
m.j. moore

This thread was discussed between 22/10/2010 and 24/10/2010

MG MGA index

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