2015 Scarab 195 HO Impulse runs slow at only 6000rpm

[MichaelN]

Was hoping someone could help steer me in the right direction as there are NO Scarab mechanics around my area.
I have a 2015 Scarab 195 HO Impulse with about 245hrs. Recently I have have been experiencing the boat being very sluggish and running rough during low speeds.
Typically I was able to run the boat around 38-40 mph at top speed. Now it only runs a top speed of 24 - 26mph with WOT at 6000 - 6100rpms. Then at lower speeds, closer to no-wake speed the boat runs pretty rough, almost like it is missing. At WOT the boat is smooth, just not cruising at its full potential.

Recently the oil pressure sensor was replaced due to a code and the boat running in lump mode. This fixed the limp mode issue, but immediately after putting the boat in the water, the recent sluggish performance was noticed. Under the suggestion of a mechanic, I had the spark plugs replaced, but no difference.

It almost feel like there is no boost as I would typically hear and "feel" the supercharger kicking in.
So, I feel like it is a supercharger issue, but wanted to get some advice from fellow Scarab folks to see what possibilites there are to explain this. Is there a good way to "self diagnosis" this problem?

The last time I took the boat into the shop (3hr drie away) with a small oil leak, they replaced an o-ring and a small plastic valve. The parts...$197. The labor...$1900. So as you might guess...I am not eager to put the boat in the shop right away without at least some idea of what could be going on.
I am trying to sell the boat, but want to be honest with anyone that might want to purchase it. BUT if the fix is relatively inexpensive I might consider keeping it.

Any ideas and/or help would be greatly appreciated!!

 

[Sidarousmg]

a couple of questions: has the supercharger ever been rebuilt? if so, by whom and how long ago? which engine do you have, the 200 or 250 hp?

 

[Scarabscott]

I have a 2019 scarab 300 and had similar issue, turned out to be the intercooler has sound deadening mat on top of it and its wedged in there pretty good, well the matt got wet over time from water like a soogy sponge and that ate at the aluminum intercooler causing a whole/leak causing the loss in boost.

 

[MichaelN]

I have a 2019 scarab 300 and had similar issue, turned out to be the intercooler has sound deadening mat on top of it and its wedged in there pretty good, well the matt got wet over time from water like a soogy sponge and that ate at the aluminum intercooler causing a whole/leak causing the loss in boost.

Thank you for the response. I don't see any leaks at all...oil, water, coolant, etc. So I am not sure if that is the issue, but I will certainly check that.

 

[MichaelN]

a couple of questions: has the supercharger ever been rebuilt? if so, by whom and how long ago? which engine do you have, the 200 or 250 hp?

The supercharger has never been rebuilt and the engine is the 250. This is why I am leaning towards the supercharger.
The sad part is that I have NO ONE in my area (Indiana) that can work on Scarab boats, so I wanted to try and do as much self diagnosis as possible before driving it 4-5 hrs to drop it off for service.

 

[Luc Lafreniere]

I'd definitely have that supercharger rebuilt (or purchase the new "maintenance free" (spoiler, not actually maintenance free)) supercharger.

Otherwise, have you inspected the pump at all? Based on your description, I'd start there.

 

[blthlt]

I'd definitely have that supercharger rebuilt (or purchase the new "maintenance free" (spoiler, not actually maintenance free)) supercharger.

Otherwise, have you inspected the pump at all? Based on your description, I'd start there.

I wouldn't drive that boat much until that supercharger is checked/rebuilt. It can come apart and do massive damage to the engine.

 

[Sidarousmg]

+1 for the supercharger rebuild. at 250 hours and 10 years old, it very well may be your problem, and they have a history of grenading if not maintained. you can do it yourself, it's about 2-3 hours to remove it and send it out to be rebuilt, another 2 hours to put it back in. costs about $5-600 parts, labor, and shipping. one other thing you could check on, since you have the 250hp engine, you also have an external intercooler. at least in the seadoo version, they are known to leak and start sending water into the engine intake. checking it is relatively simple, just remove it and inspect, if there is any amount of water inside, you have a leak that could be causing your symptoms and should be addressed ASAP.

 

[MichaelN]

+1 for the supercharger rebuild. at 250 hours and 10 years old, it very well may be your problem, and they have a history of grenading if not maintained. you can do it yourself, it's about 2-3 hours to remove it and send it out to be rebuilt, another 2 hours to put it back in. costs about $5-600 parts, labor, and shipping. one other thing you could check on, since you have the 250hp engine, you also have an external intercooler. at least in the seadoo version, they are known to leak and start sending water into the engine intake. checking it is relatively simple, just remove it and inspect, if there is any amount of water inside, you have a leak that could be causing your symptoms and should be addressed ASAP.

I'd definitely have that supercharger rebuilt (or purchase the new "maintenance free" (spoiler, not actually maintenance free)) supercharger.

Otherwise, have you inspected the pump at all? Based on your description, I'd start there.

So the shop that I normally drive to said that they need to pull the engine to replace the supercharger which is quite expensive in labor costs.
I have never seen the supercharger on that boat (I will look this weekend), but is the shop right or can I truly do this replacement on my own without really screwing something up? I am pretty mechanic and do my own work on my truck, so is it that difficult or do I need a licensed boat mechanic to take on the task?

Also, if I read correctly...the new "maintenance free" superchargers came out in 2017...are these compatible with an older Scarab engine?

 

[Sidarousmg]

you can certainly remove the supercharger yourself, it's a little tight and you need a special wrench/bit, but you can easily get it. PWC muscle is where i had mine rebuilt when i had my old seadoo. they sell the torx wrench that you will need if you don't have it, they also have a step by step video for removing and installing the supercharger. it's on a jetski, but same exact engine. i'm not certain about the compatibility of the "new" superchargers to the older engines, @Luc Lafreniere may know more than i do about that subject.

 

[Luc Lafreniere]

It is definitely possible, but I haven't done it myself. I don't think there's anything to it. But you can see a person that just got this done recently: In need of superchargers for 2014 215HO

@John P Jones care to give your advice? Would you rebuild them or go the new supercharger route considering costs?

 

[MichaelN]

I found the following supercharger to order just in case that is the issue.

$869.99* GENUINE BRP no tax* 5490673 MAINTENANCE FREE SUPERCHARGER (BRP'S old part number was 0461943) *In Stock & Ready To Ship!

turbo, fan, jet, super, charger, 461943, BRP, 461943, SUPER CHARGER, 461943

www.cecilmarineonline.com

As I understand it, BRP is updating their computer system and will not start taking orders again until August 25th with ship dates well after that.

Also it was suggested to look at the Standard Motors RY232 relay as if this has a bad connection or is faulty I could have fuel/ignition issues with the boat. Has anyone had this issue or know if that statement is more valid than a supercharger issue?

 

[Luc Lafreniere]

The relays can cause engine start issues, but not lack of power no. I do recommend however to have spare relays on hand just like fuses. Scarab/BRP should provide some inside the fuse box like the fuses.

It's entirely possible this isn't a supercharger problem, but regardless, you're overdue for a rebuild or new supercharger. So I'd definitely do that and see if it fixes the problem. If not, move on to the next possibilities. But I wouldn't dodge that supercharger in case it blows up on you and causes way more damage to your engine.

 

[MichaelN]

@Luc Lafreniere Thank you and I do keep a few fuses on hand as they have already come in handy. Nothing like a fuse going out when you need them to function. Cheap items to keep just in case.

So is there any other common issue(s) that can cause what my symptoms are beside that supercharger and probably more the clutch or bearings inside the supercharger? The shops that I have talked to don't seem very confident in their diagnosis and of course that possibly adds up to a bunch of parts that I never needed and a huge labor bill.

 

[Luc Lafreniere]

Well the pump is the big one (my comment #6 on this thread). I still haven't seen anything in the comments about checking that. At this point, the pump should be entirely removed and inspected.

 

[Sidarousmg]

since you have the 250hp engine with the external intercooler, I would at least take a look and inspect it, doesn't cost anything but a little bit of your time., this post was from a couple of years ago, does it sound like the issue you're experiencing?

R

Thread 'Speedster Engine Surges'

Jan 6, 2022

Hello. I have a 2010 Seadoo Speedster 150 with the 255 HP supercharged engine that i bought new. Love the boat and the performace.
The problem is, I cant find anybody to service the boat anymore in Phoenix. The engine surges under load. I’ve changed the plugs, coil packs, replaced both fuel filters, fresh gas, new fuel injectors, checked fuel pump pressure (60 psi). It starts, idles great but wont accelerate, just surges badly. There is no check engine light or trouble code displayed on dash. Can anyone suggest how i can get my boat fixed. It must be one of the many engine sensors gone...

• Ron B
• Replies: 10
• Forum: Sea-Doo Jet Boats & Pontoons

 

[MichaelN]

since you have the 250hp engine with the external intercooler, I would at least take a look and inspect it, doesn't cost anything but a little bit of your time., this post was from a couple of years ago, does it sound like the issue you're experiencing?

R

Thread 'Speedster Engine Surges'

Jan 6, 2022

Hello. I have a 2010 Seadoo Speedster 150 with the 255 HP supercharged engine that i bought new. Love the boat and the performace.
The problem is, I cant find anybody to service the boat anymore in Phoenix. The engine surges under load. I’ve changed the plugs, coil packs, replaced both fuel filters, fresh gas, new fuel injectors, checked fuel pump pressure (60 psi). It starts, idles great but wont accelerate, just surges badly. There is no check engine light or trouble code displayed on dash. Can anyone suggest how i can get my boat fixed. It must be one of the many engine sensors gone...

• Ron B
• Replies: 10
• Forum: Sea-Doo Jet Boats & Pontoons

I will definitely check the intercooler out as well. Thank you.

 

[MichaelN]

Well the pump is the big one (my comment #6 on this thread). I still haven't seen anything in the comments about checking that. At this point, the pump should be entirely removed and inspected.

I will try to check everything that I can while I have it out for maintenance. The intercooler, the pump, etc.
Thank you.