engine shakes

Mine does much the same and it's probably nothing to worry about. What I think is happening is as follows: As more electrical items are turned on, the electrical load on the generator increases so it requires more power from the engine to turn it. At idle, this will slow the engine down a bit so that it can drop below the speed at which the engine will idle smoothly. The heavier the electrical load is, the more pronounced the effect is. The heated rear window and the headlights and fan are heavy electrical loads and will produce the biggest effect on the engine speed. Provided the alternator warning light doesn't come on, there shouldn't be a problem. You'll probably find that if you rest your foot lightly on the accelerator. when all the electrics are on, just enough to bring the idle speed back to normal, the shaking should return to normal too. If this is the case, then there's probably nothing wrong and dont worry about it. With regard to air leaks issue, air leaks in the induction system can indeed cause a rough idle and the inlet manifold gasket is a not uncommon source of leaks. If you've checked all the rest of the pipework and found nothing wrong, then the manifold gasket is the usual suspect. Hope this helps Martin

Hi, Have you, by any chance, checked the engine mounts and their condition?? Might be worth it while looking at the alternator... Des. . . ;)

If you do consider a change of alternator at any stage, don't! Just change the brush-box. They are only about a tenner from Braydon Motor Company. Got to be worth a go before you commit. Could well be that your brushes are worn, making the alternator not function to its full potential. Good Luck.

thanks for the replys i will take a closer look at the alternator this weekend.

Have just heard that the problem could be the vacuum lines on the carburettor. Is it possible to tighten the speedo cable in order to let the engine go with a little higher rpm? Just 100-150 rpm.