Longevity of a boat;Jet Boats such as Seadoo?

So, I'm in the market for a bass boat to buy one. However, seeing a lot of Jet Boats, such as Seadoo Challengers for sale. What is the longevity of the engine of these? Do they hold up well and is maintenance through a marine mechanic similar to that of an outboard? Not interested in an inboard/ outboard, only an outboard as that is all we've owned. But a Jet Boat seems like an interesting option.

Thoughts? Can they last as long as a well maintained outboard?

Re: Longevity of a boat;Jet Boats such as Seadoo?

One of my OBs is about 40 years old and has never seen a mechanic (impellers, plugs, etc I do myself).

My I/O is on its 29th season and its never seen a mechanic (same caveat).

My jet is 10 years old and it has all original parts as well. I've sucked up a few sticks and plastic bags, but never damaged the impeller or wear ring. The routine maintenance is done by myself here as well.

Seems to me that PMs and proper storage are the key no matter what you buy. Old 2-stroke jets we had weren't as reliabale, but the current 4-strokes are bullet proof.

Re: Longevity of a boat;Jet Boats such as Seadoo?

Ki Ki said:

So, I'm in the market for a bass boat to buy one. However, seeing a lot of Jet Boats, such as Seadoo Challengers for sale. What is the longevity of the engine of these? Do they hold up well and is maintenance through a marine mechanic similar to that of an outboard? Not interested in an inboard/ outboard, only an outboard as that is all we've owned. But a Jet Boat seems like an interesting option.

Thoughts? Can they last as long as a well maintained outboard?

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I had a 2001 seadoo challenger with the mercury v-6 m2 jet drive. I blew the engine up after personally putting about 500+ hours on it. I do not know how many hours it had when I got it, but I only used it 2 seasons.

The 5&6 cylinders had no compression, took it apart to find the top of the 5 & 6 pistons had areas that were missing, thus exposing potions of the rings. I believe it could be an oiling issue.

Loved the boat. No good for fishing, but at cruise handling cannot be compared, and in my opinion once you understand control dynamics of a jet drive I think they are easier and more maneuverable than a outboard.

Re: Longevity of a boat;Jet Boats such as Seadoo?

The 2 stroke rotax based boats are going to have the shortest life.. but on the other hand, those engines are also dirt cheap. 2 stroke mercs have the same life as a comparable outboard, as long as the oiling system holds together the engine will last forever. (which is why some guys go to premix also) Once you are talking about the 4 strokes, the realistic life will probably be longer than you keep the boat, if maintenance is kept on top of at least.

Re: Longevity of a boat;Jet Boats such as Seadoo?

I question the statements about short life on old two stroke rotax's.. I've owned many over the years and always considered them some of the most reliable, lowest maintenence engines around. I suppose "short life" is a relative term, though. I've owned the following sea-doo 2 strokes:

'90 SP 580 rotax
'95 SPX 650 rotax
'96 SPX 720 rotax
'96 HX 720 rotax

All were on their original engines, and though none had hour meters I alone put hundreds of hours on all of them with the exception of the HX which I only had for a single season I think. Who knows how many hours they had on them when I bought them. I never had a single engine related problem with any of the above; the only issues I ever encountered with simple carb adjustments, lines splitting, and a replaced starter in the old 580. I never babied them or did anything special for them, just basic maintenence. My old man has a 98 (I think) GTX as well, with the 787 110hp rotax, its still in his garage and in running condition as far as I know.

If I was in the market for an older jet boat, I wouldn't hesistate to buy a Sea-Doo with twin two strokes. And as stated, you could replace both of them with reman'ed longblocks for less then single replacement of the new four strokes. I would own nothing with a merc sport jet, though.

Re: Longevity of a boat;Jet Boats such as Seadoo?

I wouldn't hesitate to own a seadoo powered jetboat. As the poster above stated, I, too, have owned several early to mid 90's seadoo jetskis with everything from the 587 yellow engine to the 787 110hp model and they have been very reliable.

Re: Longevity of a boat;Jet Boats such as Seadoo?

spoilsofwar said:

I question the statements about short life on old two stroke rotax's.. I've owned many over the years and always considered them some of the most reliable, lowest maintenence engines around. I suppose "short life" is a relative term, though.

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Per rotax, recommended time between rebuilds is 300 hours for most 2 strokes. Nothing against rotax, I've owned LOTS of seadoos and love the 787 engine, but rotax's have a very good power-weight ratio. That means things are built lighter, and rebuilding them is just part of it. Recommended rebuild doesn't mean it will fail at that point, it just means that statistically the bell curve for failure is past the outlyers area.

Ever wonder why reman 2 stroke seadoo engines are dirt cheap? (a 787 ready to go for under $900) Supply and demand... Lots of toasted engines to provide lots of cores for rebuilding. Try finding a rebuilt outboard block for that... Not going to happen. For a similar displacement outboard, you are talking $3000+. (disclaimer, other 2 stroke PWC reman engines are just as cheap, same thing applies though... Built light, high power-weight, and low total hours between rebuilds)

And rotax 4 strokes... Great engines, as long as they aren't supercharged. Those things self destruct like clockwork, even WITH the upgraded supercharger clutch washers. (and replacement for them is NOT dirt cheap!)

Re: Longevity of a boat;Jet Boats such as Seadoo?

smokingcrater said:

And rotax 4 strokes... Great engines, as long as they aren't supercharged. Those things self destruct like clockwork, even WITH the upgraded supercharger clutch washers. (and replacement for them is NOT dirt cheap!)

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Silly SeaDogs . . . that's why real men ride Kawasaki JetSkis.

Re: Longevity of a boat;Jet Boats such as Seadoo?

smokingcrater said:

And rotax 4 strokes... Great engines, as long as they aren't supercharged. Those things self destruct like clockwork, even WITH the upgraded supercharger clutch washers. (and replacement for them is NOT dirt cheap!)

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After 2008, the clutch washers were no longer an issue. They switched from ceramic to steel. Replacing the clutch washers cost approx. $125.00 if you remove the supercharger yourself (not difficult).

Either way, the issue with the washers shattering, while common in the ski's (not a question of IF, but When), is rare in the boats.