Mercruiser 3.0L/3.0LX Sparkplugs

[info@illuminationtech.com]

Trying to tune up my 3.0LX before putting her in cold storage and have come across a spark plug dilemna. Manual shows very different plugs for these two engines, although they are virtually the same engine.<br /><br />One of the plugs is almost three times as long (inserted thread length) than the other. I have run both plug types in this engine and both sizes seem to work fine.<br /><br />What is the difference between the 3.0L and the 3.0LX engine? I think it is only the igition system, but why would that effect plug length?<br /><br />Which plug is better and why?<br /><br />What is the big difference between long and short plugs anyway??<br /><br />Thanks for any help!

 

[ODDD1]

Re: Mercruiser 3.0L/3.0LX Sparkplugs

The 3.0 L an LX have 2 different head designs....the smaller port lx head uses a 3/4" reach plug, the l uses regular 1/2" reach....I too have seen the wrong plugs in these motors, in both combinations...good thing these are relatively low stress engines...LOL....sometimes measuring thread depth in the head is the only verification you have....