Asking question for a family member... 1997 Mercury 115 wouldn't start. Compression check shows top 2 cylinders have compression of 90. If there is a crack between these cylinders only option is a new powerhead, correct?

On that note, rather than spending $3,000 on a powerhead does anybody know of any 75-150HP Mercury outboards for sale?

Call Charlies out board shop in Alvarado and talk to either Charlie, Keith or son and they could tell you what they have and you can bet the engines will be in top shape.

What was the compression of the remaining cylinders and what leads you to think there is a crack between cylinders?

90 is not dead, it's sick.
It could be a simple power tune treatment could bring it back from it's carbon sick bed.

Something is definitely wrong because those motors normally have 140lbs or better.

Bottom 2 cylinders are 150lbs. Top 2 were only 90 and the mechanic that looked at it told him chances were it was cracked between the cylinders. Also said tearing it apart to make sure was going to cost more than it was worth, he should just find another mercury motor that will use all of the same controls. I would imagine it could be a bad head gasket, warped piston or something of that sort but the mechanic was sure it was a crack between the top two cylinders since it was those two side-by-side cylinders that had low compression. I'll relay the message and I would imagine he will have another mechanic actually tear it apart and fully diagnose. Thanks everyone!

I would get a second opinion. Cracked block would give a zero compression. Something else is going on.

PM sent on 2001 150 XR6 for sale

Quick look with a bore scope would end the mystery.