Spark plugs for reading -- 1988 OMC 5.0 (502APRGDP)

[jbutler67]

I value the feedback and advice on this forum. Looking for help reading spark plugs. This is from an old rig (1988). Trying to gauge how many more seasons in her -- and ultimately, if i should invest any more in her.

These plugs are 2 weeks old. Have been out on water 3 times with these plugs. Usage ranged between low RPMs (1,000 to 1,200) in no wake and up on plane for short stretches of 3-5 minutes at a time around 3,200 to 3,600 RPMs.

Spark plug #2 looks very interesting compared to the others.

Compression tests taken last month before first outing on water while engine was still cold.
1 - 150
2 - 160
3 - 160
4 - 170
5 - 150
6 - 150
7 - 150
8 - 160

 

[Bondo]

Ayuh,.... Compression numbers look Great,....

Spark plug colors will generally only tell ya what the motor was doin' in it's last minutes of runnin',....
If anything, those look to be runnin' slightly lean,....

Have ya examined the contents of the fuel filter for water lately,..??

 

[jbutler67]

I have not looked at the fuel filter recently. I'll do that today.

Appreciate the great advice and feedback on this forum. I hope to someday be able to assist others.

Thanks!