1988 Mercury 100 hp pops out of gear when traveling forward above 2500 RPM's.

[x96riley3]

I recently bought a used boat, (1988 Sea Ray Seville) and all of a sudden yesterday as I travel forward the motor pops out of gear whenever the boat goes above 2500 RPMs. It's like all of a sudden it's in neutral. The motor runs great and travels ok until we start to pass the 2500 RPM mark and then "BAM" the motor revs up like it's in neutral or something. I'm new to the boating world and I've owned the boat for less than 2 weeks. Any suggestion on what the problem might be and a cost estimate would be very helpful. Thanks in advance!

Motor: Mercury 100 hp

 

[Chris1956]

Re: 1988 Mercury 100 hp pops out of gear when traveling forward above 2500 RPM's.

Does it actually make a loud noise, or just rev up? If it just revs up, it is likely a spun prop hub ($50 problem). If it gives a loud bang, the gears are slipping. Post back, and we can assist a bit more.

 

[x96riley3]

Re: 1988 Mercury 100 hp pops out of gear when traveling forward above 2500 RPM's.

It doesn't make any noise. It shifts into gear ok and as we slowly give the boat more throttle it simply jumps into neutral right around 2500 RPMs or so. We would simple put the boat back into gear and as long as we didn't pass 2500 RPMs, we were fine. We were about 5 miles out in Lake Michigan when this all started. We were able to travel just below 2500 RPM's all the way back to the dock.

 

[Chris1956]

Re: 1988 Mercury 100 hp pops out of gear when traveling forward above 2500 RPM's.

So the gearshift moves and allows the motor to go into neutral? That is a Mercontrol problem, however, I don't think you meant that.
Let me know.

 

[x96riley3]

Re: 1988 Mercury 100 hp pops out of gear when traveling forward above 2500 RPM's.

I think it's the clutch dogs or a spun prop after reading the internet for hours.

 

[Chris1956]

Re: 1988 Mercury 100 hp pops out of gear when traveling forward above 2500 RPM's.

When a clutch dog slips, it makes a loud bang. Since you do not hear that, it is lilkely a spun prop hub. Do you have a spare prop? If so, try it. if the issue goes away, take the prop to a prop shop for a re-hubbing.