2017 response txi question

[Conor]

Do any other 17/18 response owners have performance issues? I have been prop hunting since I bought the boat and think I have figured out why I can’t land on one. My boat noticeably loses power as the temp changes. It feels like it is losing as much as 20% from a morning set to an afternoon set when temp has increased 15-20 degrees. I have never experienced this on any previous boat I have owned. I know there is some power loss with temp, but it seems like too much. I have gotten many complaints from women about hole shot power. Every other boat on my lake has more power along with a nautique 200 with the same engine. If I took this boat up to some of the high lakes in my area I’m afraid it would barely get on plane! I Have tried every prop acme has sent and every prop OJ recommended. One prop gives decent hole shot but puts rpms too high and another struggles to pull a skier around turn island above 23mph at WOT. My dealer hasn’t been much help. They are obviously focused on surf and wake boats. Don’t really care about one ski boat vs 100 surf/wake boats. If I had known the frustrations that came with my new super expensive 2017 malibu response txi I would still be in my 2011 prostar 197. Any help would be great.

[Ilivetoski]

How many hours are on the boat? I have read from multiple people that those engines aren’t broken in until around 200 hours, after that a lot of power issues seem to go away

[MISkier]

It’s an air intake temperature issue. Need to vent the engine box better (supplemental blower) to keep the intake air temp (IAT) below 130.

 

MC had a similar problem a few years ago on the Prostar.

 

These motors need air. Lots of it.

[bbruzzese]

i have an 18 and agree...although I'm not suffering the same issues that you're describing, it definitely seems weak for a 6L. I'm sure my '15 TXi had much better power out of the hole. that said i've heard that lifting the engine cover slightly may help the engine breath a little more. Haven't tried it myself but seems pretty simple so might be worth a try.

[BraceMaker]

It is somewhat surprising that they dont have a vented inlet on the dog house which would seal on the inlet and take in only outside air.

[RAWSki]

Have heard and experienced similar issues .but have yet to hear a definite solution. Perhaps the engine needs more air? I.E MC "double blowers". I was shocked at the lack of holeshot when I recently skied behind a brand new 18 Txi .

[MISkier]

@RAWSki, you are on the right track.

[swc5150]

Sorry for the hijack, but does the Prostar secondary blower make a big difference? Mine was one of the last built without it, and they've offered to install one, but my boat doesn't seem to lack any power. The hole shot is easily as strong as my 196's were (even in 100 degree weather), so I was not planning on doing the retrofit...it looks kind of rigged IMO. But now I'm wondering if my boat has more power than I'm aware of. I'm also only at 27 hours, so the motor should beef up even more in time. Regardless, should I have it installed?

[MISkier]

@swc5150, if they are covering it under warranty, I’d probably get it. If you don’t like it, disable it in the future.

[bbrannan]

@Conor You’re not alone. Our ‘17 and ‘18 have both been slow, even at mildly high (80s) ambient temps. As mentioned above, this is because the engine de-rates the timing at high intake air temperatures. The air intake is at the front of the engine box, but the vent is in the rear, so it pulls in heated air that has been sitting in the insulated engine box. Furthermore, the bilge vents under the windshield face outwards, not forwards like the 196/200. 175 hours and counting.

[DW]

@Conor : Your power loss case seems a bit more extreme compared to others, it does sound like high intake air temps are a culprit. The hot air is rising to the top, right where your air intake is.

You might try the following: 1. crack the engine box open, you can simply put something to lift the leading edge by ~ 4-6". If that helps but does not totally cure the problem, I would try to pipe cool air directly to the inlet, either pop off the filter and attach a 4" (stiff) dryer hose and run that down and out the front of your engine cover (you can simply cover the end with a panty hose rubber banded around the tube for a test) or simply run the hose up right at the filter so it can draw ambient air rather than the heated air. Make sure you clear the belt.

Warm or hot fuel will also reduce power as that heats the intake charge, so maybe insulating the fuel lines would help.

[bbrannan]

@DW If the outside temp is over ~85 degF, our boat struggles to get to 36 mph by the 55s at our 2,150 ft lake. I’d say that is “extreme” power loss, relative to the theoretical power of a 6 L engine. Elevation is just 350 ft.

[jstaab3]

Miskier is correct, engine compartment is not getting enough air, take off motorbox and pull a skier and you will be amazed!! I had to add a blower moving air in the motorbox to get me 18 to perform correctly the boat is awesome once you get it to run properly

 

Jason Staab

[UWSkier]

Isn't this the same engine as was in the '15s and '16s?

 

Is the through-stringer ventilation gone from the newer boats? I know the older ones all had air intakes under the windshields that fed directly into the engine compartments.

[BraceMaker]

 

What did these things sound like to be sucking past your head.

 

Makes more sense to put the scoop in the bow and have a specific duct to the engine

 

[keithh2oskier]

@BraceMaker that looks like an early 2000's MC. Got any photos of the entire boat? Looks like a hot rod.

[powbmps]

Has anyone received any info from Malibu regarding this issue?

 

Also curious as to what explanation there would be for an engine taking 200 hours to break in? That seems a bit strange.

 

[BraceMaker]

@keithh2oskier - believe it was a skifly boat.

[DW]

I made my own engine box and incorporated a slot opening with a duct to the inlet, so it is basically a cold air box setup. The intake air hiss actually sounds very nice.

 

[swc5150]

Alan Jackson's PS had a blower too (yes, the country star).

[The_MS]

Skied and drove the new Malibu on Monday. Hole shot sucks, in course no prob and it drives like a 200. Much better driving then our MC but fit and finish not as good. Loved the pull.

[Dacon62]

Malibu’s have a long history of having a hidden air intake slot just above the 3 cup holders at the back of the motor box. Worked good for cold air in when moving and warm air out when sitting. An unfortunate side effect was it would warm up your beerverage very quickly. Think ‘17 - ‘18 got rid of this slot?

[The_MS]

Why just hole shot?

[evolski]

Is there someone from Malibu able to give some details here? Was looking at a new one, but now have some concerns as we're on a shortish lake. I checked MalibuCrew and didn't see anything.

[ski4xtc]

We had both a 2017 and 2018 TXI on a short lake and at high altitude. We did a lot of experimenting along with putting an outside temperature gauge in the engine box with the temperature display in the phone holder. The engine air intake temperature does not rise much if you are running the boat constantly. A bigger problem is when you come back to the dock and the boat sits between skiers. We would find the temperature in the box to climb 25 to 35 degrees while sitting just for 10 to 15 minutes. There was then a noticeable difference pulling the next skier out of the hole and getting up to speed quickly. After all the experimenting, we found the biggest help was to open the engine cover between skiers to let the hot air out and stop the heat from building up.

[jjackkrash]

One of the reasons I sold my 2000 Am. Skier and popped for a new boat was I didn't want to deal with the gas vapor lock from a hot engine box anymore (and a few other quirks). Not quite the same issue, but I did the whole open the box between sets thing, cut holes in the box and add vents and a fan thing, dump cold water on the fuel line thing to get it started, and a few other hack fixes, which I could justify to myself on a $12k boat, but which got pretty old.

 

But a brand new big dollar ski boat? I'm pretty tolerant of minor issues, but I'd be screaming for a real fix or demanding my money back on an issue that is killing the hole shot.

[LeonL]

I know for sure that the boat referenced by @bbrannan had the 2x4 propping up the engine cover trial to no avail. I also know that Malibu is aware of the problem and they haven't found a solution. The sad part is that it's time that all the promo members are trying to move their boats and they're gonna be a hard sell.

[RAWSki]

Perhaps there is more of a difference between the Crusader 6L and the PCM engines than just paint and fittings??

[LeonL]

@RAWSki there is an obvious difference in the ECM, I would say. As I stated in a previous thread, a high level guy at Malibu told me they haven't received a decent level of support from PCM on the problem.

[jpwhit]

@LeonL, Having a lot of experience w/ embedded software in the auto and industrial space, the way I would interpret "a high level guy at Malibu told me they haven't received a decent level of support from PCM on the problem" is that Malibu is unhappy that PCM won't code around Malibu's design issue by changing the engine power derating algorithms in the ECU.

 

There are good reasons the ECU derates power when intake air temp is too high related to engine durability. A software workaround is always the most economical solution to a design issue like this, but in this case Malibu needs to fix their engine box cooling issues. If I owned one of these boats, I'd be worried about the long term effects on engine durability in addition to the power issues.

[UWSkier]

Does anyone know if there was different software programming for the engines on the '17-18 boats? The '15-16 boats came with the 6L Crusader as an option. @mlange has one but it lives in WI where temps don't tend to be an issue. Haven't heard of any of those feeling low on power but they're less common as most came with the 5.7.

[evolski]

Has anyone tried taking the plastic covers off? Fan belt and the red top cover to allow for better air flow?

[mlange]

Yep. Never felt down on power w/ my '16 w/ the Crusader 6L over the last two years, although it is Wisconsin.

 

The only think I notice is that if the engine heat soaks for 10 mins after pulling a few sets that it takes a bit longer to fire up - an extra second or two. I'm assuming it's the fuel pump working a bit harder to fight against vapor lock.

[MISkier]

Our 2016 TXi never had any power loss issues. Great boat all around. The 2017 had some power loss, but not terribly bad. The club has a Nautique now. But, the 2018 TXi I drove recently had significant power loss issues.

[jpwhit]

@UWSkier, I doubt the differences between various model of the boats is due to differences in ECU programming. I would think they all have similar algorithms to protect the engine when certain conditions are reached such as high intake air temperature.

 

I suspect the difference is more related to the design of the various version of the engine boxes and venting. If the input air temp to the engine never gets above the limit, then the power derating would never happen on the earlier models even though the same algorithms are implemented in the ECU software.

[bbruzzese]

45 degrees here in VT this morning and the thing was a beast...up to speed 3-4 boat lengths sooner. Probably a dumb question but would running the blower when stopped help on hot days?

[LeonL]

@bbruzzese I doubt that the blower moves enough CFM to make an impact, but run it all the time. What can it hurt?

[ski4xtc]

@bbruzzese in our many tests, we noticed no difference in running the blower. The only way to keep the power up was to lift the engine cover between sets to stop the heat from building in the engine compartment when it was sitting.

[BraceMaker]

I always rev up in neutral and watch my engine temps drop before shut down. I think youll find it removes a lot of the potential heat before it soaks into the upper end. Could probably also do this on restart to pull heat out.

 

A water cooled intercooler off the raw water intake would be fairly easy to implement could run through the bilge under floor and pull air from a bow vent chill it and not have intake temp rise.

[jjackkrash]

I would seriously consider sending the dealer a letter demanding a real fix or demanding a lemon-law buy back. If they get a few of those letters it might make them more motivated to provide a real fix.

[Conor]

The last time I spoke to someone from malibu factory, they said they hadn’t heard there were any problems with these boats. Have any of you other 17/18 owners voiced your frustrations to malibu?

[Roger]

@swc5150 - I have a 16 ProStar and have disabled the extra blower. It made zero difference (except no more annoying blower sound). I've not timed it to speed, but I believe the boat is up to speed in about the same distance Summer (90 plus degrees) or Winter (50s... okay, I'm in South Florida). Anyway, John Shealy had disconnected his (also a 16) and recommended trying it and I've never even thought of re-connecting it.

[Chad_Scott]

I know Jason Staub Malibu Promo guy from Kansas was having these issues and installed another fan in the engine compartment and seemed to keep his air intake temp in check. If I’m not mistaken it was a very inexpensive solution. I’m going to ask him to chime in on here

[jstaab3]

I installed a 3 inch blower, and ran a 3 inch hose up the stringer on the port side to draw in cool air and supply air to the engine. before i had this the engine would not perform do the the intake air being to hot and the engine would not produce the correct amount of power out of the hole or while pulling a skier. Once i had this completed, it dropped my intake air temps to around 130 based on the temperature out side, at the last tournament the outside temp was 96 and i was able to keep my intake temps at 132 while the boat was pulling skiers. I also cut out the plastic on the back of the motor box under the silver billet to help the heat escape. If anybody would like to see pictures for how i did please Message me and i will send them to you. The boat is clearly a whole different animal if the engine can breath!!!

 

Jason Staab

[Chef23]

Very disappointing that you have to do that to a 70-80K boat. I also find the extra fan on the Prostar annoying it makes it loud inside the boat.

[UWSkier]

@jstaab3 how are you measuring intake air temps?

[MISkier]

@UWSkier, it is available in the diagnostics screen at the helm.

[jhughes]

What sort of alternate physics are going on inside a Nautique motor box where the engine has a consistent amount of power without a fan?

[UWSkier]

@jhughes must be the sea-deck :)

[DW]

@jhughes: plenty of available airflow, it seems that the inlet side is not getting enough attention on some of these boats.