Early-90's 90HP Johnson VRO issues

[natelg]

Last summer my family broke down and finally bought a used speed boat on the cheap. Though the thing works, we don't think it works to its full potential. It's a 17' Sunbird something or other with a 90HP VRO Johnson on the back. Unfortunately I don't have the exact specifications.
We did get a "tune-up" recently, but I don't think they did a particularly good job... plugs & wires are new though.
Could anyone give me some ideas on how to make the boat behave a bit better...?

Here are the issues:
-Stalls out at idle or low RPMs (We have to "pulse" the throttle to get through 5mph zones)
-Seems to be taking increasingly longer to start (Used to start right away, seems to take longer and longer...)
-Takes a really long time to accelerate/get on plane. (Kind of killed our hopes of water skiing behind it...)
-We did have an issue with the engine cover consistently knocking a plug wire loose, but we managed to fix that one ourselves.

Thanks ahead

 

[strngcru99]

Re: Early-90's 90HP Johnson VRO issues

there could be a million and 1 things wrong here... first i would pull the plugs and check the condition and then check the compression.... you could have anything from a fould plug to the wrong prop. if the plugs come out black and your compression is okay all you might need to do is decarb it.. i'm sure you will get many more replies also... this is a execlent forum

 

[natelg]

Re: Early-90's 90HP Johnson VRO issues

Okay, thanks for your response.

I know its a pretty open question, unfortunately I just don't know enough to narrow it down.

Will the plugs come out black even if they were changed in the past month or two?

Unfortunately I can't run out back and check either, the boat's docked 2 hours north for the season.

 

[strngcru99]

Re: Early-90's 90HP Johnson VRO issues

a little black is okay but if its really caked you have a carbon issue. if you can find a serial number on the info tag you can take that to a dealer and they can give you all the info you'll need on the motor. a shop manuel helps alot to!