Originally Posted by
pascalfd
How to tell a #4 from a #5 ?
I have been using a #4's in the summer and #5's rest of the year here in GA. I have all my still good plugs in the same bag and now realize I can't tell one from another
.. no marking I can tell. Any way to tell a #4 from a #5 ?
You should be able to tell by looking at the side of the glow plug actually. The #5 has a small 5 imprinted in the side of one of the flats that the glow plug wrench goes over and the #4 should have a 4 on it. We've been doing this for a while now so unless you have some early plugs they should be on there. Otherwise take a look at the glow plug element, the wire diameter on the #4's is smaller than the #5's.