Older Merc 50HP on 16' Bayliner

[JJ13]

I just purchased an 83 bayliner 16' with an older merc 50HP motor. I took it out today and it ran good. My question is that I could reach 30+ MPH but it took it awhile. It purrs like a kitten, but seems to be lacking the get up and go side of things. Mounted on this 16' bayliner open bow, shouldn't it be able to pull a skier or tuber? There were only two adults and three kids on the boat, and there is no way it would have pulled anything around.

Like I said it runs great but at full throttle there is no umph.

Also, after a while when we would restart it, it would idle great but then die when you put it into gear. After I let it idle for a little bit and gradually went forward it started to pick up momentum. ?????

Any ideas would be great. Is the motor to small? Thanks for your time and advice in advance.

JJ

 

[rdgordon1@cox.net]

Re: Older Merc 50HP on 16' Bayliner

I have found that the engine will cool off after sitting idle for a while and even though it will idle after a restart it is still running too lean to support any throttle until it warms up a little.If you must advance the throttle before the engine is ready for it just stab the choke button as you advance the throttle and it should recover enough to keep running.I would consider that normal behavior.
I am sure you will get some other replies but it sure sounds like you are over propped on the high end.Try a lower pitched prop if you can but bear in mind that the engines are designed to run at an optimum RPM range at full throttle so without a tach for reference you are just guessing what the engine is turning.If you are over propped and the engine is lugging you run the risk of damaging the engine so it is important to get your setup right as soon as you can.
If you can find a similar boat and engine that is performing well you might try to duplicate his setup for a start but based on the symptoms as you describe them I would say a lower pitched prop would be a good place to start.Ron G

 

[Laddies]

Re: Older Merc 50HP on 16' Bayliner

First is it a 3 or 4 cyl 50 HP. Then you need to ck the WOT RPMs. Next you may not be trimmed right, change the positition of the tilt pin and test it.

 

[JJ13]

Re: Older Merc 50HP on 16' Bayliner

Thanks for the help. It is a 4 cyclinder. I have adjusted the tilt and no change. I am taking the advice on the RPM and prop. I will check the RPM next just to see what ballpark I am hitting in. I was also curious about the prop. The dang thing runs great and gets above 30MPH, it just takes it a lond straight away to get there. There is definelty no way we can pull the kids on a tube at the moment. Even in turns you almost come to stand still.
I will check all advice given and get back to you all. Thanks for the help. JJ

 

[steelespike]

Re: Older Merc 50HP on 16' Bayliner

When it hesitates squeeze the primer bulb if it helps you may need a fuel pump rebuild.Also try a little choke if that helps you may need to rebuild the carbs being sure that all passages and jets are clear.Speedos are notoriously inaccurate.You should check speed with a gps.

 

[khes142]

Re: Older Merc 50HP on 16' Bayliner

Hi. I run an 86 16ft capri with a 1975 85hp merc. I think you are underpowered. mine is rated for a 90hp, but I honestly think the boat could run a 90-115hp. i can tube ok with the 85hp, but can only pull teens on 2 skis.no adults or slalom skiing.my boat has a real deep vee and a pretty wide beam for its length.I have poor low speed holeshot performance after the OB gets hot. I think the reeds are worn...requires a major teardown to reach them, so I just live with it. I ski first, and tube later in the day.