Help with a 2004 GTX 4-TEC Supercharged

[MARK41]

Just took it out for the first time last night. Top end speed was only 55mph. Can anyone give me any ideas on what to check for.

 

[Michael211_2000]

Is the supercharger working? With the seats removed and on the trailer idling (either for less than 20 seconds OR hook to a waterhose!) reach down and grasp the supercharger to carb air hose and squeeze it while giving it a bit of throttle you should feel air pressure build up inside the hose under your grip.

Check the oil level, an overfull crankcase will limit the engine. The oil level should be at the MIDDLE of the bend in the dipstick NOT at the top of the bend or above!

What condition is the pump's impeller and wear ring? What was the top RPM reading you saw at 55mph?

These are the starting points at any rate.

ps. Do not run the engine for more than about 20 seconds on the trailer without water! The exhaust system can be damaged by running it dry. If you hook up to a waterhose always remember to start the engine BEFORE starting the water flow, then STOP the waterflow BEFORE stopping the engine! Failure to do this in the correct order can hydrolock the pistons and cause serious engine damage. Water flows into the exhuast manifold and can pour over into the cylinders if there are no exhaust gases to push the water out and into the waterbox!

- Michael

 

[jenx_u]

Either ck. the impellor & the wear ring

 

[Michael211_2000]

Either ck. the impellor & the wear ring

Either check the impeller & the wear ring... or what?

- Michael

 

[JFizzleJR]

What are the engine RPM at full throttle?

The more you run an engine with a blown supercharger the better the chances are of bits and pieces destroying the oil pumps and engine internals. Instead of running it 20 seconds on the trailer I advise removing the air intake hose off of the supercharger inlet and, with the engine OFF, try to spin the supercharger impeller by hand. If it moves more than a fraction of an inch it needs maintenance. If it spins free, the clutches are gone and you have a big job ahead of you.

Is the supercharger working? With the seats removed and on the trailer idling (either for less than 20 seconds OR hook to a waterhose!) reach down and grasp the supercharger to carb air hose and squeeze it while giving it a bit of throttle you should feel air pressure build up inside the hose under your grip.

 

[Michael211_2000]

The more you run an engine with a blown supercharger the better the chances are of bits and pieces destroying the oil pumps and engine internals. Instead of running it 20 seconds on the trailer I advise removing the air intake hose off of the supercharger inlet and, with the engine OFF, try to spin the supercharger impeller by hand.

You're worrying about the pebbles AFTER the avalanche... if it's blown, the damage has already been done 10X over. 20 seconds or 5 minutes more, won't change anything if the SC washers (or the supercharger itself) have failed. IF it's fallen apart inside the engine, it's already done the damage. He already "took it out" for a ride like this after all.

Somehow I don't think Mark's coming back here though so it's probably a moot point. If a new poster doesn't come back within a day or two of getting replies, they usually never come back. :-(

Regards.

- Michael

 

[JFizzleJR]

Better safe than sorry IMO, but to each his own. The charger boost doesn't come on until about 6000 RPM anyway. And revving on the trailer isn't healthy. The engine won't overheat with the hose on but the carbon seal can burn up quickly. You're probably correct in saying 1 time isn't going to hurt anything, but I personally wouldn't want to take any chances when all I have to do instead is undo 1 clamp to check if the supercharger wheel spins by hand.

You're worrying about the pebbles AFTER the avalanche... if it's blown, the damage has already been done 10X over. 20 seconds or 5 minutes more, won't change anything if the SC washers (or the supercharger itself) have failed. IF it's fallen apart inside the engine, it's already done the damage. He already "took it out" for a ride like this after all.

Somehow I don't think Mark's coming back here though so it's probably a moot point. If a new poster doesn't come back within a day or two of getting replies, they usually never come back. :-(

Regards.

- Michael

 

[Michael211_2000]

Better safe than sorry IMO, but to each his own. The charger boost doesn't come on until about 6000 RPM anyway.

I can feel the pressure on mine with just 1 quick rev up to ~3k rpm on the trailer. I'm not sure what the exact definition of "boost" is, but the SC does increase the air pressure in the hose with just a little throttle I have felt it myself. This isn't something you would want to do on a daily basis mind you. I'd NEVER hold throttle on the trailer! However the owners manual in the "exhaust cooling system flushing" section states "Run the engine about 20 seconds at a fast idle between 4000 - 5000 RPM." I think I'll pass on that though! LOL!

Ever had the air hose come off the carb at ~5K rpm's while cruising? I have! You'll DEFINITELY notice the difference the engine instantly loses power and rpm's, it feels sluggish until you stop and put the hose back on (I had problems with mine popping off last summer, I finally cleaned it with Formula 409 degreaser really well then clamped it back down and it hasn't come off since... it would however blow off at far less than 6K rpm's!). I'm just saying....

And revving on the trailer isn't healthy. The engine won't overheat with the hose on but the carbon seal can burn up quickly. You're probably correct in saying 1 time isn't going to hurt anything, but I personally wouldn't want to take any chances when all I have to do instead is undo 1 clamp to check if the supercharger wheel spins by hand.

Yeah but it's not quite that easy to reach that 1 clamp and pry the hose off... it's kind of a reach and the hose is often stuck on the SC outlet (in my experience; mine was blowing off at the carb last summer mind you not at the sc). My RXT has an air vent tube in the way also which has to be removed 1st and then reinstalled afterwards.

OTOH I can easily reach the hose where it goes onto the carb throat without removing or unscrewing anything which is why I recommend this technique if in doubt of SC functionality. It's a quick tool-less way to check. You're not going to make things worse with this quick check. If it's broke, you're already going to be sorry! LOL! But I agree with "to each their own".

ps. The carbon seal doesn't heat up THAT quickly, keep to under 5 minutes of idle time on trailer with waterhose on flush port as per the owners manual it'll be fine... and the engine WILL eventually overheat on the trailer (if you leave it running far enough past 5 minutes) using a waterhose on the flush port it has no cooling the ride plate get's hotter and hotter the longer it runs!

There are times when you have to run them on the trailer in order to check engine functionality, there's no getting around it and they are designed to run like this for short periods of time without harming anything. The exhaust cooling flush port is your friend, as long as you use it right!

- Michael

 

[JFizzleJR]

OK, I see what you're saying now about checking the supercharger to throttle body hose...

That statement from the owner's manual about a "fast idle" at 4000-5000 RPM is funny. Sometimes I wonder who writes those things!

Yes, I've had my intercooler couplers blow off many times. You're talking to someone who designs and sells aftermarket intercooler kits for these Seadoos LOL. Popping an IC hose off is the same feeling as the supercharger clutch being gone. It's much louder once you have metal pipes hooked up though. It's almost scary the kind of loud whistling sound it makes.

I wouldn't advise anyone run the ski on the hose for more than 1-2 minutes at a time, regardless of what the manual states. The carbon seal won't necessarily "fail" so-to-speak from running on the hose for 5 minutes, but there's a good chance it will shorten the life of the seal. I suppose this applies more to modified machines than stock ones. The higher HP really makes it a struggle sometimes just to keep a carbon seal intact for a few races, let alone a whole summer.

The point you make about accessibility is a good one. I often need to be reminded of the perspective of how things are when tearing into a fully put together OEM ski. 99% of the time I'm doing the opposite. My supercharger to throttle body hose has been long gone. It's been almost 7 years since I've seen it. I tossed the vent tube years ago. It wasn't as bulky and attached as the seat support setup like your RXT, but the sentiment is the same. My skis spend more time in pieces than together, mostly for development purposes (luckily, I guess?).

I agree, the exhaust flush port is your friend. It's a shame that some people don't know it's there and others don't know to turn the engine on first, THEN the water :willy_nilly:

I can feel the pressure on mine with just 1 quick rev up to ~3k rpm on the trailer. I'm not sure what the exact definition of "boost" is, but the SC does increase the air pressure in the hose with just a little throttle I have felt it myself. This isn't something you would want to do on a daily basis mind you. I'd NEVER hold throttle on the trailer! However the owners manual in the "exhaust cooling system flushing" section states "Run the engine about 20 seconds at a fast idle between 4000 - 5000 RPM." I think I'll pass on that though! LOL!

Ever had the air hose come off the carb at ~5K rpm's while cruising? I have! You'll DEFINITELY notice the difference the engine instantly loses power and rpm's, it feels sluggish until you stop and put the hose back on (I had problems with mine popping off last summer, I finally cleaned it with Formula 409 degreaser really well then clamped it back down and it hasn't come off since... it would however blow off at far less than 6K rpm's!). I'm just saying....



Yeah but it's not quite that easy to reach that 1 clamp and pry the hose off... it's kind of a reach and the hose is often stuck on the SC outlet (in my experience; mine was blowing off at the carb last summer mind you not at the sc). My RXT has an air vent tube in the way also which has to be removed 1st and then reinstalled afterwards.

OTOH I can easily reach the hose where it goes onto the carb throat without removing or unscrewing anything which is why I recommend this technique if in doubt of SC functionality. It's a quick tool-less way to check. You're not going to make things worse with this quick check. If it's broke, you're already going to be sorry! LOL! But I agree with "to each their own".

ps. The carbon seal doesn't heat up THAT quickly, keep to under 5 minutes of idle time on trailer with waterhose on flush port as per the owners manual it'll be fine... and the engine WILL eventually overheat on the trailer (if you leave it running far enough past 5 minutes) using a waterhose on the flush port it has no cooling the ride plate get's hotter and hotter the longer it runs!

There are times when you have to run them on the trailer in order to check engine functionality, there's no getting around it and they are designed to run like this for short periods of time without harming anything. The exhaust cooling flush port is your friend, as long as you use it right!

- Michael

 

[Michael211_2000]

That statement from the owner's manual about a "fast idle" at 4000-5000 RPM is funny. Sometimes I wonder who writes those things!

Agreed! That's just fast, no idle about it! What were they thinking?

Yes, I've had my intercooler couplers blow off many times. You're talking to someone who designs and sells aftermarket intercooler kits for these Seadoos LOL. Popping an IC hose off is the same feeling as the supercharger clutch being gone. It's much louder once you have metal pipes hooked up though. It's almost scary the kind of loud whistling sound it makes.

I can imagine. Heck I ran low on fuel once last summer and I almost jumped off my RXT when it emitted this super loud BEEP (low fuel warning, scared the cwap outta me!).

I wouldn't advise anyone run the ski on the hose for more than 1-2 minutes at a time, regardless of what the manual states.

I go for under 5 minutes, usually just 1-2 minutes is all that's needed to check something anyhows or pump the exhaust cooling system full of RV antifreeze for winter storage.

The carbon seal won't necessarily "fail" so-to-speak from running on the hose for 5 minutes, but there's a good chance it will shorten the life of the seal. I suppose this applies more to modified machines than stock ones. The higher HP really makes it a struggle sometimes just to keep a carbon seal intact for a few races, let alone a whole summer.

Again, it's a matter of keeping perspective... you're worrying about the pebbles after an avalanche again. Your modified race machines are a whole nother beastie IMHO; you're going to be replacing parts MUCH more frequently than the average rider (well, most average riders anyhow). In this forum, most of the machines are going to be stock or near stock and ridden by average people who might like going ~60-70mph on occassion but spend most of their time in the ~40+ mph range doing donuts and jumping boat wakes, cruising around and stuff. We're not running WOT 99% of the time or more! At least, I'm not. LOL!

The point you make about accessibility is a good one. I often need to be reminded of the perspective of how things are when tearing into a fully put together OEM ski. 99% of the time I'm doing the opposite. My supercharger to throttle body hose has been long gone. It's been almost 7 years since I've seen it. I tossed the vent tube years ago. It wasn't as bulky and attached as the seat support setup like your RXT, but the sentiment is the same. My skis spend more time in pieces than together, mostly for development purposes (luckily, I guess?).

I understand where you're coming from, sounds like that could be fun especially if you're getting PAID to do this development (oh what a dream job that's be!!!!). But for reliability and safety I try to keep as much of the OEM equipment as possible. I'm not planning to put in a Riva Stage 3 upgrade kit, ever... it's more than fast enough as it is. Minor improvements I have made include an R&D Aquavein intake grate and a Solas 13/18 impeller, and when the supercharger is ready for a rebuild I'll probably go with a slightly better aftermarket wheel and aftermarket seals at least but nothing extreme I don't want to change the injectors or anything like that.

Do you fill your ride plate bolt holes? I could not believe how BRP left those bolt holes open like that that's terrible drag very inefficient I filled those suckers flush and then sanded them even flusher (I can still break the epoxy out with a screwdriver and small hammer if I ever need to replace the plate... I put duct tape over the bolt heads before filling with marine epoxy so there's not epoxy around the bolt heads themselves)!

I agree, the exhaust flush port is your friend. It's a shame that some people don't know it's there and others don't know to turn the engine on first, THEN the water :willy_nilly:

Ditto! And then there's the folks who don't check their drain plugs BEFORE launching... LOL! ROF!

Regards and have a great summer man!

- Michael

 

[JFizzleJR]

LMAO I had the same reaction when the low fuel warning first came on. My first mod was 3 pieces of electrical tape placed over the holes where the alarm sound comes out. If you want to quiet it down a little and still be able to hear the warning beeps loud and clear I suggest putting just one piece of tape over the holes. They're located near the base of the handlebar setup on the outside of the ski. Look from the front of your ski and you'll see them.

I'm sure Seadoo left the rideplate holes open for servicing purposes. That way a tech can get at the plate quick and easy with no hassle (except for the bucket-full worth of silicone) if it needs to come off for whatever reason. Plus, until they came out with these new GPS speed limiters they could use all the drag they could get to slow these skis down from the factory per their "agreement" with the Coast Guard. It's good to hear you filled the rideplate holes properly. Do the same for the intake grate holes if you haven't already.

When it's time for a supercharger rebuild the best option IMO is to replace your charger with the X charger. With the stock air intake and stock intercooler (internal IC) you will be fine with the stock 38 lb/hr fuel injectors as far as AFR goes.

Agreed! That's just fast, no idle about it! What were they thinking?

I can imagine. Heck I ran low on fuel once last summer and I almost jumped off my RXT when it emitted this super loud BEEP (low fuel warning, scared the cwap outta me!).

I go for under 5 minutes, usually just 1-2 minutes is all that's needed to check something anyhows or pump the exhaust cooling system full of RV antifreeze for winter storage.

Again, it's a matter of keeping perspective... you're worrying about the pebbles after an avalanche again. Your modified race machines are a whole nother beastie IMHO; you're going to be replacing parts MUCH more frequently than the average rider (well, most average riders anyhow). In this forum, most of the machines are going to be stock or near stock and ridden by average people who might like going ~60-70mph on occassion but spend most of their time in the ~40+ mph range doing donuts and jumping boat wakes, cruising around and stuff. We're not running WOT 99% of the time or more! At least, I'm not. LOL!

I understand where you're coming from, sounds like that could be fun especially if you're getting PAID to do this development (oh what a dream job that's be!!!!). But for reliability and safety I try to keep as much of the OEM equipment as possible. I'm not planning to put in a Riva Stage 3 upgrade kit, ever... it's more than fast enough as it is. Minor improvements I have made include an R&D Aquavein intake grate and a Solas 13/18 impeller, and when the supercharger is ready for a rebuild I'll probably go with a slightly better aftermarket wheel and aftermarket seals at least but nothing extreme I don't want to change the injectors or anything like that.

Do you fill your ride plate bolt holes? I could not believe how BRP left those bolt holes open like that that's terrible drag very inefficient I filled those suckers flush and then sanded them even flusher (I can still break the epoxy out with a screwdriver and small hammer if I ever need to replace the plate... I put duct tape over the bolt heads before filling with marine epoxy so there's not epoxy around the bolt heads themselves)!

Ditto! And then there's the folks who don't check their drain plugs BEFORE launching... LOL! ROF!

Regards and have a great summer man!

- Michael

 

[Michael211_2000]

LMAO I had the same reaction when the low fuel warning first came on. My first mod was 3 pieces of electrical tape placed over the holes where the alarm sound comes out. If you want to quiet it down a little and still be able to hear the warning beeps loud and clear I suggest putting just one piece of tape over the holes. They're located near the base of the handlebar setup on the outside of the ski. Look from the front of your ski and you'll see them.

Good to know it isn't just me that freaked out when that alarm went off. I'll look for the speaker holes and see if a single layer of black electrical tape won't tame that thing down just a bit. ;-)

Any way to mute it after the low fuel alarm starts blaring? 1 long beep is enough to get my attention I KNOW I'm low on fuel I'm heading back to the dock already, does it have to keep going off every 30 seconds or so afterwards? That is annoying!

It's good to hear you filled the rideplate holes properly. Do the same for the intake grate holes if you haven't already.

I filled and smoothed out the intake grate bolt holes with the same black RTV silicone I used under the intake grate when installing it. Everything under the hull is as smoothed out as I could make it.

Are you serious about the Coast Guard agreement to limit top speed from the factory? I've never heard that story before.

When it's time for a supercharger rebuild the best option IMO is to replace your charger with the X charger. With the stock air intake and stock intercooler (internal IC) you will be fine with the stock 38 lb/hr fuel injectors as far as AFR goes.

What does the X Charger get me though? Is it more reliable, or more powerful, or both? Can I tell where other Mutants are and what they're doing? Oh wait that's Professor X I'm thinking about now! My bad!

Seriously though I know nothing about the X Charger, it's aftermarket right? What does it get me that I need or really want above and beyond the OEM supercharger? Thanks.

- Michael

 

[JFizzleJR]

It never shuts up. That's why I taped over it. On my ski you can barely hear the 3 beeps it makes when the key is plugged in.

The Coast Guard argeement is real. They aim to keep the skis limited to 65 MPH with a passenger.

The X charger is the stock supercharger on the 255/260 models. It will give you more acceleration and speed. The difference in reliability is negligible, especially considering Seadoo has been including these chargers on their own stock machines since 2008. It's $750 for a new X charger or $300 + labor for a rebuild. I know of dozens of people who go for the new X charger instead of rebuilding their standard 215 charger. It's a direct swap as far as fitment is concerned.

Good to know it isn't just me that freaked out when that alarm went off. I'll look for the speaker holes and see if a single layer of black electrical tape won't tame that thing down just a bit. ;-)

Any way to mute it after the low fuel alarm starts blaring? 1 long beep is enough to get my attention I KNOW I'm low on fuel I'm heading back to the dock already, does it have to keep going off every 30 seconds or so afterwards? That is annoying!



I filled and smoothed out the intake grate bolt holes with the same black RTV silicone I used under the intake grate when installing it. Everything under the hull is as smoothed out as I could make it.

Are you serious about the Coast Guard agreement to limit top speed from the factory? I've never heard that story before.



What does the X Charger get me though? Is it more reliable, or more powerful, or both? Can I tell where other Mutants are and what they're doing? Oh wait that's Professor X I'm thinking about now! My bad!

Seriously though I know nothing about the X Charger, it's aftermarket right? What does it get me that I need or really want above and beyond the OEM supercharger? Thanks.

- Michael