Mercruiser i/o 5.0 troubles

[debbie1112@verizon.net]

Engine runs fine at slow speed. When I throttle up the engine races & won't go any faster forward or reverse.1995 Sea Ray.First real problem.

 

[WAVENBYE2]

Re: Mercruiser i/o 5.0 troubles

It could be alot of different things (Tune up etc...) water in gas. Have you done any thing to it since winter??? Not enough info.

 

[debbie1112@verizon.net]

Re: Mercruiser i/o 5.0 troubles

The boat ran perfect so far this season.I had it out at least 5 times.I did check the prop. It seems fine. I did all the usual maintenance.Although I didn't change fuel filter. The engine is in mint cond. I bought it last year & never had a problem with anything.

 

[WAVENBYE2]

Re: Mercruiser i/o 5.0 troubles

OK what your saying is engine is running good, just not picking up speed? Sounds like your rubber hub in the prop. is slipping. How did you check the prop?

 

[debbie1112@verizon.net]

Re: Mercruiser i/o 5.0 troubles

I took the whole prop off & checked all the parts. I did replace the propeller nut & tab washer because it appeared to be burnt at the end of the nut.The shaft was fine. All the grooves were fine on the shaft & hub.

 

[debbie1112@verizon.net]

Re: Mercruiser i/o 5.0 troubles

I just realized you mentioned rubber hub. O.K.Ireally didn't check that.Let me check it first thing tomorrow & I'll get back to you. Thanks!

 

[ziggy]

Re: Mercruiser i/o 5.0 troubles

scribe a line on the hub that splines to the prop shaft. put a corisponding line on the prop and run it. after the run. if the lines are no longer lined up. the hub is slipping. or ya could try a different prop too..........other two options for engine runs good but boat don't go would be spent coupler or internal drive damage like gears or drive shafts broke.......

 

[Haut Medoc]

Re: Mercruiser i/o 5.0 troubles

I just realized you mentioned rubber hub. O.K.Ireally didn't check that.Let me check it first thing tomorrow & I'll get back to you. Thanks!

You cannot visually inspect the hub & see if it is bad......
Put your spare prop on, if you don't have one, get one.......
Take the one that is on there to a prop shop & have it rehubbed.......
If the engine did not overheat & the boat will still move it is likely that the coupler & the drive are OK.....
Perform the test that Ziggy outlined if you want to be sure, but I'll wager a new prop will answer that question.....​

 

[debbie1112@verizon.net]

Re: Mercruiser i/o 5.0 troubles

Just want to thank you gentleman for all your help. I replaced the rubber hub & the boat is fine.

 

[Bondo]

Re: Mercruiser i/o 5.0 troubles

Thank You Debbie,.......

It's Always Nice when a poster comes back with an Up-date on their Problems,.........
Especially when We Helped with the Fix...........