Mechanic says I lost compression from gas line

[Jamicostco]

I have a 98 150 Mercury and up until yesterday it ran like a champ. We sucked up some sea grass and it reved pretty high and we immediately shut it down. Towed it in and took it straight to the marina mechanic. (I think it overheated but no warning bell) He says it's shot.. $4600 to rebuild the power head. Blamed my gas lines. This makes no sense to me. I've supposedly got zero compression in one of the cylinders. It ran perfectly fine on Sunday. I have a feeling I'm being screwed with. The owner of the marina seriously has his eye on my boat and has been trying to get me to sell it to him for over a year (which I have zero desire to do). Unfortunately I don't have anyone reputable local to get a second opinion. Could a clogged gas line cause loss of compression? I am thinking it would bog out completely but not kill it to beyond hope. Any input is appreciated, I'm new and green lol. Ty

 

[Iceman66]

Just start it up again and see if you have cooling water,
does it run smooth at idle?
If it does, take it fore a ride and see how it runs.

If no cooling water,most lately your impeller has gone dry and a you have to replace it.

 

[MH Hawker]

Or stop by advance and get a compression tester and run the test your self.

 

[Dukedog]

Or stop by advance and get a compression tester and run the test your self.

This...and. Don't run it till ya do it. Your so called "mechanic" is full of it. Not sayin' its not broke but that's not tha cause. Screwed up fuel lines usually won't do anything but make it run bad, run outta gas or not run at all...........Killin' a cylinder is usually caused by, 'lectrics, something in tha hole turned loose or heat.......Just something ta think about as for a "fuel line" causin' a lean condition. Dependin' on which fuel line and where it is it would cause a minimum of TWO cylinders to go lean. Possibly all six. Dependin' tha location......

 

[SeaKaye12]

On multiple carburetor engines a restricted fuel line could theoretically cause a lean-run condition in the cylinders fed by the affected carburetor. Maybe that's what the mechanic meant?

In any case....compression numbers don't lie. If you've got zero in any of your cylinders.....the engine needs to come apart. Whatever caused it is sort of a moot point.....although it is imperative that the cause ultimately be narrowed down so as to prevent it from happening again.