Corvette LS1 Option
LS-1 Engine Malfunctions
It is hard to believe it is nearly ten years from when I bought the LS1 powered Malibu and began a webpage dedicated to it.
Hopefully this information will be useful to some folks, particularly those looking at the older Malibu LS1 powered boats.
Back in 1987 I bought my first ski boat, a Malibu Skier for a mere thirteen grand brand new. At that time I didn't demo a Nautique because of its well deserved reputation for having too high of a wake. I did, however, demo a MasterCraft, but was unwilling to pay the three grand(!) premium over the Malibu even though the wake was clearly better. While I later wished I'd spent the extra bucks, the Malibu Skier served me faithfully and well for the thirteen years I owned it, all at very low cost. It was a true work horse, requiring nearly no maintenance and willingly giving year after year of skiing fun.
BOAT SHOPPING, FALL 1999
The fall '99 I thought I was finally ready to replace the Malibu Skier. All along, I'd considered Malibu, Mastercraft, and Nautique as the best in the industry. But, with Mastercraft off my short list of candidates (at that time they still had the hull that during AWSA testing lost control and ran up on the shore), I only had two left, Malibu and Nautique. This time I wasn't going to scrimp on quality of construction or wake to save money. However, I will concede that probably any tournament boat produced today is damn good compared to the '80's when there was huge differences between brands. I demoed the 2000 models in October 1999 in smooth and rough water.
Unquestionably the Nautique's wake had become world-class. Low and extremely soft. Quality of construction still superb. Loved the digital dash, including several different ways to monitor speed. Against expectation, it was very easy to read even in direct sunlight. The boat felt and sounded extremely solid when underway. That stuff they put on the inside of the hull seems to pay off. However, there were a few things I didn't like. I don't like the right hand prop rotation - pulling away from a dock in reverse. Hated the back end of the boat. It sloped so much that trying to sit on it with a dry suit (admittedly slick) was not just difficult, but hazardous. It was all I could do to keep from sliding off and I considered it downright dangerous. I'd have to put traction strips on it if I'd bought it. Didn't like the graphics or the color choices. Also didn't like how the rear seat back had to be raised and then pull equipment forward into the boat. An item of note on Nautiques is they always use a 1.23:1 gear reduction, then prop accordingly (13X16). I think that is a major contributor to the soft wake (slower turning prop for the same speed).
I also rode in a Nautique with a factory 502 CID. Actually the most impressive part was watching it from the shore. From a dead stop it literally jumped vertically, exposing the first two fins completely and only about an inch of the third fin in the water - and that was with six adults onboard. Not that I like horsepower or anything. Or torque.
The Malibu I liked, but still couldn't quite get myself to plunk down the bucks. Their quality had improved immensely. It was like a completely new manufacturer made it. I liked how it looked much better than the Nautique (hey, I want beauty AND a flat wake), including the available chrome underwater gear, etc. I just liked the layout and "usability" of the boat better. The wake was truly very flat but not as soft as the Nautique's.
How my "needs" changed when I received the January 2000 issue of WaterSki Magazine! The Corvette LS1 engine was available as an option, something I'd drooled over in the early 90's Corvette-engined MasterCraft. That engine was enough to push me over the edge to finally give up my faithful old '87 Malibu. For 2000, the LS1 was an all-aluminum block, saving 300 lbs. It cranks out about 375 HP, more than the car due to the lack of exhaust restrictions, and 380 lbs. of torque. Redline is 6,000 RPM. The specifications really are quite amazing - stuff like hollow crank and cam journals to reduce rotating weight, six bolt mains, etc. And if you get one of these engines, note that an onboard computer not only logs hours separately from the dash hour meter, but it logs what RPM's are run at what time so they can tell if it was broken in correctly, among other things. It also has a temperature sensitive variable speed rev limiter that makes sure you don't over rev when it is warming up. The LS1 engine option includes all-chrome underwater gear and a closed cooling system (the aluminum block can't have sand flowing through it - and closed cooling means you can't have a hot water shower). I was planning on paying for the fuel injection option over a base carbureted engine and getting the chrome underwater gear anyway, plus I was "wishing" for the closed cooling system. Well, add those options up and I convinced myself I was only paying roughly a grand or two for the LS1. Isn't "logic" convenient at times!
I headed to the January 2000 boat show so I could talk to a factory rep. Much thanks to Mike Kelley. He patiently put up with two solid hours of questions and gave me fabulous advice. The boat I ordered turned out to be "better" because he was involved.
I decided to go with an open bow since the hull is exactly the same as the closed bow model. In fact, Malibu literally jig saws an opening in the bow and then upholsters it. Since my state's marine board passed the spotter law a few years ago, I'm finding I take out more people. For many years I skied mainly as a twosome and rarely over three on the boat. Now I usually have at least four so the extra space is useful.
Malibu uses a "Wedge" in the back to simulate 1000+ lbs. of weight at the back of the boat for wake boarding. I'm primarily a water skier, but I like to play around with a wake board and this gives a better wake for a board and still maintains the ideal slalom wake - without the time to fill and drain an extra water tank like some manufacturers do. There is a little door in the ski platform to access the pins to raise or lower the Wedge. I think the Wedge shows real innovation by Malibu. It makes a notable height increase in the wake - more than I really want at my wake board skill level (now there is a misuse of the term "skill"!). You will run the boat at a little slower speed for the optimum wake board wake when using the Wedge than you normally do without one. It also lugs the engine quite a bit (your engine speed is higher for a given MPH with the wedge), which makes sense since the hull is sitting deeper in the water and is pushing more water.
The single color interior of the Corvette Limited Edition looked classy to me, so I went with a single color interior which was close to the interior of my tow vehicle. A single color is definitely not the typical but it came out great and stands out from the crowd. That "wood" dash and steering wheel are also too classy to do without. If Malibu would have allowed the option of a single color hull back then, I would have done that too (red, of course).
Malibu also has a two battery switch option. The battery switch allows current to be drawn from either or both batteries. Get it 'cuz some day you'll need it!
||I brought over my Alpine CD head unit, two Alpine amps (500 watts total), and two sets of 6.5" MB Quart speakers from the old boat. I've always been partial to Alpine decks and Quart speakers. This time I went with two 10" JL sub-woofers and added an alarm system. Boy does this puppy rock! I understand Quart now makes a high end water resistant speaker, but haven't heard one so can't vouch for the sound quality.
||Brought over the trailer wheels matching the Ram from the old Malibu trailer.
To say that I was pleased with the Malibu at this point of development in the year 2000 would be an understatement! From the colors to the LS1 engine, to the chrome underwater gear, to the sterio, I was in boat skier heaven.
The four-blade buzz: I've talked to an awful lot of people about three vs. four blade props and most say the same pitch in a four blade will drop a couple MPH off the top end and give greater hole shot. However, greater hole shot means getting to 36 MPH a few feet faster, not something that you're going to feel much in the seat of your pants. Everyone agrees they are quieter and vibrate much less. Most say they give a better wake.
Some say you should drop about an inch in pitch, some say stay the same, some say increase a little to compensate for the drop in top speed. Few people pay attention to how much cup a blade has (which makes a huge difference in the prop performance), with the notable exception of Acme. Acme recommends .080" cup for most applications.
As near as I've been able to find out, the LS1 engine should use nearly the same prop as a "regular" engine. I went into this expecting the additional 1000+ RPM and 135 horsepower over my old Malibu would require something dramatically different, but it takes a lot of horsepower to push just a few more MPH faster so you end up very close to the same setup.
Choices: From the research I've done, I think two of the four-blade prop manufacturers have distinguished themselves from the rest of the field. I have an admitted strong bias for stainless steel (I've heard all of the arguments for and against, and I'm "for").
The four blade "Power Max" prop from prop from Acme Marine Group (call Bill at 888-661-2263 or 231-592-0470). This company has done quite a bit of research really knows their stuff. Their main claim to fame is machine milling props so they are extremely accurate, something the other manufacturers have difficulty with, particularly if the cup is hand-hammered. Acme will build a prop to match your exact specifications and mills the cup to a thousandth of an inch. In March 2000 I'm told that MasterCraft tested the Acme prop against OJ's and Acme props were measurably faster out of the hole AND had a higher top speed, although being ten feet faster to 36 mph isn't something you'll notice seat-of-the-pants. However, don't expect to get it in stainless.
||The second is the Cutter Marine Performance prop. It's claim to fame is the largest surface area for a four blade prop and it does carry an impressive profile. It just looks like it would push more water. Last I checked, they only carry 13X13.5 props. However, I've talked to Randy Sneesby (800-800-7564 Ext.204) and he says they will tweak your prop if you return it to them with an explanation of what you'd like it to do differently.
Malibu's experience: I'm only aware of Malibu testing what I believe is a 13X14 four blade OJ NiBrAl (which is only $20 less than the Cutter stainless). From those tests they say to expect a DECREASE in BOTH hole shot and top speed! I'm unaware of their testing any other four blade prop. Feedback I've gotten from other people leave me thinking OJ is definitely not a leader in prop performance. However, I see that for 2002 Malibu uses CNC props. I haven't received feedback from anyone about them. A word of caution: A few LS1 boats were shipped with a three blade with 12.5 pitch (to allow it to hit higher revs - ideally should be about 5,800 RPM wide open according to Indmar). Further use has shown that this blade is so overpowered by the engine it cavitates terribly - like a badly slipping clutch when revved. Contact Malibu if you are having this problem.My experience: I've been intrigued by four blade props from way back, well before they were cool. About 1990, I tried a four blade on my '87 Malibu Skier. It had hardly any cup, engine speed went up about 300 RPM at skiing speeds. The wake was harder and higher. It was a disaster. I returned it immediately, but always wondered what it would have been like if I'd been able to play with cup and pitch. At that time I was unable to find one single person who'd tried or even heard of anyone trying, a four blade prop, so I abandoned it as something that was beyond my financial means to experiment with to find "perfection." My 2000 Response came with a 13X13 stainless OJ three blade ("M" blade, with less cup than the "Mad Dog" on the 325 HP engine). It tops out at 5,500 RPM (6,000 RPM Redline) and 51 MPH. At 35 MPH it turns 3,400 RPM.
I purchased a Cutter Marine stainless 13X13.5 four blade. My impression is the wake is a little flatter but I wouldn't say softer. Naturally it has notably less vibration and thus runs quieter. I think it has better "bite" out of the hole (particularly that first few RPM). It goes up about 100 RPM over the three blade at skiing speeds and it definitely drops top speed, topping out around 5,400 RPM and a corresponding 47-48 MPH. That's ok by me. Since smoothness and bite out of the hole is important to me, I'm happy with the four blade. If top speed matters to you, definitely stick with the three blade - Update: Ok, ok, I have come to the conclusion that for the higher horsepower engine the three blade is probably the preferred prop, but I just like four blades. I must admit I think the four blade makes a slightly harder wake, probably due to the about RPM increase over the three blade.
When I got the boat with the three blade it pulled very hard to the right at wide open throttle (WOT), but was pretty neutral at skiing speeds. The four blade didn't pull to the right as hard at WOT. However, after getting the rudder replaced from hitting rocks, both props acted close to the same, but this time they both pull slightly to the left at skiing speeds and slightly to the right at WOT. When dropping from WOT to a slower speed, there is a very defined point (46 MPH) where the steering wheel quickly switches which side is pulling - it is a bit weird to have the boat do that little "dance" so quickly when decelerating. I don't have any idea if the slight differences between the rudders was intentional design change by Malibu or just variations in manufacturing, but there is a definite difference, so I don't know what to say for someone else to expect. Malibu has finally adopted a tunable rudder, something Nautique has had for some time.
The 2003 hull, I've been told by a dealer, was redesigned enough that the LS-1 gets about five MPH more than the 2000 hull. Of course, further hull redesigns have happened since 2003.
Well, I previously had a blurb about how great the rates were at Ski Safe. However, one year they raised the rates 28% over the previous year even though I never had any claims. When I called to ask what was up, I was flatly told that in the last year the rates for Malibu Boats had gone up. No Shit! So, I went insurance shopping. Long live Costco Insurance. Got insurance through them for 45% less. That now makes the house, truck, car, and boat insured through Costco, saving me hundreds per year.
CORVETTE LS1 ENGINE MALFUNCTIONS
Indmar engines have a three year warranty. Four months out of warranty and with a mere 67 hours on the engine, it blew a gasket on the oil filter adapter plate, dumping all the oil in the bilge. Normally, Malibu works with Indmar on warranty work, but they chose not to become involved. Indmar wouldn't cover it either so was on my own. The local dealer would only replace the entire engine and that was cost-prohibitive (well over ten grand). I found a great little boat engine shop that rebuilt it for under $3,900, although afterward he did admit he underbid it.
Turns out there was a gasket slightly leaking coolant (a rubber O-ring which should have been paper) on the pressure sensor, a valve cover seal that was stretched out past the edge, and the seal between the oil filter block and engine block was paper instead of metal-backed teflon like it was supposed to be from the factory. At least some of these problems had to come from either Malibu or Indmar, although the first dealer (no longer handling Malibu) worked on it and could have contributed some but not all of those problems. I can say I am very unimpressed with the workmanship and even less impressed with either Indmar or Malibu's willingness to back manufacturing defects. Anyway, running out of oil spun two bearings. Those were replaced with oversize bearings and the crank journals ground down. Surprisingly, the valves were already worn below spec so those were replaced also. Fortunately the cylinders and pistons were fine so those didn't have to be bored oversize.
Note that you can only get parts from GM for the LS-1. No third party guys offer any internal parts.
The repair shop confirmed the engine manufacture date as 1998. It isn't uncommon for boat engines to be at least a couple years older than year of the boat was manufactured, but I thought at least the LS-1 would be current.
This wasn't my first problem with the Corvette engine. In 2001 the alternator bracket broke off , shredding the serpentine belt and thrashing the intake filter - ending a ski vacation on the first morning (and turning an 800 mile drive into a half-hour of skiing), but at least those problems were covered under warranty.
I have no doubt my experience is highly unusual. None-the-less, once burned, twice shy. Let's just say my next boat won't be powered with a Corvette engine. In part due to these experiences and in part because I am currently involved in activities that leave me with very little time to ski, I sold this boat the summer of 2004 (with a mere 73 hours!!).
That said, I have to confess I still rank Malibu in the top three. Their annual improvements continue unabated and the wake continues to improve. Hey, they finally even added a tunable rudder, something I sorely missed on my two Malibu boats.
I'll buy another ski boat someday - but the next one will be most likely be a Nautique because I like the soft wake from the oversize prop spinning at a lower RPM. We'll see how all three compare when I'm back in the market.
In spite of all the problems, it sure was hard to see that Malibu leave though. Kinda like breaking up with a very, very hot but abusive chick - too bad, but what a relief!
Check out the very active Malibu Owners discussion forums at www.MalibuBoatOwners.com.
A special THANKS to Malibu Boats for featuring the first version of this web page on their web site news page the summer of 2000 (which was naturally much more complementary at that time!)
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