79 Ski Nautique 3000rpm max!?

Just picked up a 79 Ski Nautique with the 350. I brought it to my mechanic and had timing done, carb cleaned, new plugs, general look over.

Boat starts right up, runs smooth, in neutral I can rev it right up with no hesitation... once in gear it is smooth acceleration to 3000rpm and roughly 30mph top speed. This can't be normal, everything I heard this boat should pull hard out of the hole compared to my old 3.0L mercruiser.

It has a 13x13 prop, I am new to inboards so any help please, like I said it seems to be running smooth, just not a there!

Thanks in advance, sorry for for long post...

He did not water test. When I dropped it off the boat ran very rough. What should the advance be?

Like I said I found it weird the motor revved up to 4800 rpm near instantly in neutral, and sounded very strong. But was sluggish in gear.

Ok thanks for the guidance, I am very new to these boats and will call the mechanic today and ask what the advance was set at.

Is a 13x13 a good prop for this boat?

SNobsessed wrote: Also have him check that the secondaries are opening.

8122pbrainard wrote: Ian, Did he check to see if the secondary's are opening?

Chris,
My ADD must be rubbing off on you?!!

Maybe you should check your secondaries

BTW the only way they'll open is under load so hopefully he's running this on the water after he does work on it

Just to add a little to what Pete said your advance should be about 10 at idle (some might say 6 ) and as speed goes up the advance should go up to numbers like 12 at 1000, 20 at 2000 and hit about 34-36 at 3000 or so just to give you an idea. Those are not hard and fast numbers, just an example.

Otherwise if the timing isn't advancing fully, like Pete said, it's time to check weights and springs.

13x13 is a good prop and it was the original prop on SN's from that time.

You should end up at 4500+ RPM's and 45+ MPH if things are straightened out.

KenO

FirstNautique wrote: Maybe I should see if he checked the secondaries!

What did he actually do to the carb? Hopefully just not a quick exterior spray with an aerosol!

Thanks for all the input guys, I will post as soon as I hear back from him.

Right. That boat should top at 38mph on just the primaries

Also double check the firing order and plug wires, two jugs not firing will max out about 30.

ebay dizzy fixed link

what kind of issues could this give me in this case? should i change to a marine distributor?

So if i put on the proper distributor, a marine one that doesn't have the vacuum advance, it should theoretically run better and not blow me up?

FirstNautique wrote: So if i put on the proper distributor, a marine one that doesn't have the vacuum advance, it should theoretically run better and not blow me up?

Yes on both counts

Points or electronic would be your choice.

A picture or part number for each would be good to be able to make sure it's a marine distributor and keep your body in one piece.

order a DUI marine distributor for a small block chev no matter what else you do. make sure you have a marine carb if not park it somewhere til you buy a marine 600 cfm carb. if you dont have both currently dont play with it. stop. Buy what you need and start over.