Kostas,


I would generally say no.

If the best specific solution is the cold A5 and the universal #8 can also be used, the A3 may be too hot and will require the mixture to be set significantly richer, so as to prevent the engine from suffering from detonation.

You would actually see that you can close the needle further, without risking a lean-run (which is actually detonation), when using the cold A5, compared to using the hot A3.

The price difference between the two is equivalent to the difference in fuel consumption for 15-20 minutes of running...

That is all.

I would not recommend using the A3, unless there is no other glow plug and you must run the engine NOW (and the fuel waste for these one-two flights that you MUST make, is reasonable).

Replace the A3 with the more suitable A5 glow-plug, ASAP!