Took the boat out yesterday for its first shakedown cruise. I must say I was pleasantly surprised. Boat started right up. Idle was a little low. Let it warm up on the trailer, checked bildge, no leaks. Ran on trailer about 20 mins, adjusted idle and we were off. We ran for about 45 mins then stopped for a swim for about 20 mins. Started right up and we were off again. Max RPM was around 5900 and 48 mph. What a fun little boat. This is my first jet boat. Have had many center consoles and cruisers. Handling was a little different than a conventional drive. Interesting how the wind and waves affected the boats tracking. Seemed like lots of understeer with a beam wind and/or sea. Is this normal? I guess it makes sense as no drive acting like a rudder. How are these pulling a skier? I did notice a slight bow rise coming out of the hole, looking forward to trying Aqauman's extended ride plate. The only other thing was neutral doesn't seem to be neutral. A slight foward way so I guess that needs to be tweaked. Other than that a good first run. Think this will be a fun little boat
First Shakedown Cruise
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Dr Honda
Well-Known Member
Yes... wind, and waves will push you around some. The reason is... on a conventional drive, you have a rudder. (even if it's a big I/O unit) that will help you track. With a jet boat... you really only have the chines in the hull... and they don't do a lot.
Now... the up-side to this is... you can spin the boat, and scare the cr@p out of your passengers. I even do it will my big Islandia. (good fun) Now... couple the fact that you don't have a rudder, and since you don't have a gear box to shift... you can pivot the boat on it's axis. With a little practice, you can maneuver, and park your boat better than ANY regular drive. (With the exception of some of the new multi engine, joystick controlled stuff)
The drifting in neutral is kind of normal. Since your pump is always spinning, and you are just diverting the water with the bucket... SOME movement is inevitable. With that said... if it seems excessive... then yes... you can adjust the cable, to slightly lower the bucket, and that will help. But remember... when maneuvering... (unlike a gear box) F-N-R isn't a switch. You can use the control lever to your advantage, and add small amounts of a direction, to really fine-tune your entry to a trailer, or dock.
Congrats on the maiden, and have fun with it.
Now... the up-side to this is... you can spin the boat, and scare the cr@p out of your passengers. I even do it will my big Islandia. (good fun) Now... couple the fact that you don't have a rudder, and since you don't have a gear box to shift... you can pivot the boat on it's axis. With a little practice, you can maneuver, and park your boat better than ANY regular drive. (With the exception of some of the new multi engine, joystick controlled stuff)
The drifting in neutral is kind of normal. Since your pump is always spinning, and you are just diverting the water with the bucket... SOME movement is inevitable. With that said... if it seems excessive... then yes... you can adjust the cable, to slightly lower the bucket, and that will help. But remember... when maneuvering... (unlike a gear box) F-N-R isn't a switch. You can use the control lever to your advantage, and add small amounts of a direction, to really fine-tune your entry to a trailer, or dock.
Congrats on the maiden, and have fun with it.
henryb
Active Member
Wow, sounds like you had the great "first run". I know starting those engines are a bit of a trick... make sure you learn how to use the fuel enrichment valve, as it is a gravity fed, so you have to leave the key in the ON position and let it "feed" the carbs and then it usually starts right up. Also a really strong battery (or run with 2) is also a key for success.
Again that is seriously hot max RPM's... the factory manual spec's out max rpms between 5250-5750. So yours is pretty high. It also might be that your tach is a little off? Would be good to put a tech reader to get the actual rpm's to see how close your gauge is reading.
That is one thing that is for sure... it is a fun boat!!! Absolutely, it doesn't track like an outboard or stern-drive, as they have a steg that provides that rudder type of directional control. Even most inboards have a center skeg and a rudder... our boats don't have any of that! So they kind of skim over the water and are effected by wind and waves more then other types of boats. Also I find that weight distribution inside is a big factor for how these boats steer and ride.
The Extended ride plate is by and far the best enhancement to these boats. It will allow for quicker planing, smoother ride and illuminates any porpoising that they boats can experience. It will certainly help with pulling skiers.
That is a fairly common trait, you can take the throttle control out and tweak it around a bit to get it closer to bang on Neutral. However, the trade off is that you may end up with the Forward shift position not pushing the reverse gate all the way up to the "locked in Forward" position. You will be able to tell if that is the case, when you see the shifter lever shudder around alot in a power turn... and even sometimes it will flip into Neutral or even Reverse. So it is probably more important to ensure it "locks" into Forward, then to get a perfect Neutral.
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Thanks Henry. Yeah I was wondering about the RPM. I'm thinking it may be a gauge error. Tough to tell between 5750 and 5900. I did remember to turn the key to run for a second or two before starting. Seemed to work.
Do you have experience pulling a skier? Wondering how the boat does getting a skier up from deep water and also tracking pulling a slalom.
Do you have experience pulling a skier? Wondering how the boat does getting a skier up from deep water and also tracking pulling a slalom.
henryb
Active Member
Ya, there really isn't much between 5750 and 5900, only about 3% difference! If you don't get a start on first crank, then you can leave the key in the ON position for up to 30 seconds (according to the Mercury M2 operators manual)... I find that 10 seconds is plenty.
I have pulled skiers with mine last summer... certainly it is no Ski Nautique, but it does a fair job, gets adults up on a slalom ski very quickly. It tracks fairly straight for your average recreational skier. However, I used to be a competitive skier back in the day, so I can pull the back end around a bit... but my wife didn't seem to have much trouble making corrective steering inputs. Those results may differ for really heavy adults, I'm only 175lbs, and with age, I try to be as smooth as possible carving turns rather then muscling it around any more
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Dr Honda
Well-Known Member
I'm running 6300 RPM. :thumbsup:
That's really where the extra HP comes from between the 210, and 240. Some guys will push the 2.5L Merc up to 10,000 RPM's for racing. They seem pretty safe up to 7500 rpm for recreational use. (but you have to balance them)
If your pump is in good shape... you can pull a skier easy. BUT... slalom will be dang near impossible. An aggressive, heavy skier will pull the boat.
henryb
Active Member
Wow, every time the Dr posts something, I learn something new! That is very encouraging! So when I eventually get a rebuild, I could be getting a nice power boost over factory spec 210Hp. Woohoo!
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Dr Honda
Well-Known Member
Yep...
On the 210 engine... you will have to remove the rev-limiter, and put in the bigger reed cages. It will take either a case mod... and the new cages, or getting a new lower case. (That's needed to flow more air)
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