Merc XR4 over revving when throttling up

[mdrussell2]

I have a 1991 Mercury XR4 i bought about a month ago. Last night after running boat all day I throttled up on motor and had sudden loss of power much like when i had spun a prop in the past I putted back to shore thinking i spun my prop but it was fine. it will engage in drive but wont go over 5mph soon as i try to throttle up it over revs and goes nowhere. PS the boat is a 1996 skeeter ZX180. Any help or ideas would be appreciated.

 

[The_Kid]

Re: Merc XR4 over revving when throttling up

Hard to tell if the hub is bad by looking at it, unless you had previously marked it. When my hub went out I could I could do a little faster than idle. Any more throttle when trying to get on plane just raised the RPM without any more speed.

 

[mdrussell2]

Re: Merc XR4 over revving when throttling up

so when you say hub are you talking about the entire lower unit or is there a specific part or assembly i can replace

 

[BIGFLAT]

Re: Merc XR4 over revving when throttling up

I'd try swapping out the prop... BF ( The hub is a rubber type shock absorber inside the prop where the splines go onto the propeller shaft.. They can get worn over time.) Hope that's what it is, cause a lower unit is BIG BUCKS...