1984 Johnson 140 no compression

[DTE]

I have a 1984 Johnson 140 with o compression in #4 cylinder the other 3 have 90. I removed the head looks like corrosion or something all over piston no holes cleaned off and replaced gasket still no compression

 

[Faztbullet]

Most likely dings from broken ring pieces...time to rebuild

 

[Bosunsmate]

yep pull the bypass cover for that piston and have a look

 

[interalian]

What does the head gasket look like? Pictures? We like pictures.