Supercharger play question.

[drtyhatch]

Ok we pulled the hoses off of our two rxp's to check the chargers to see if they spin. There is a tiny amount of play on both chargers when turned left and right but they are extremely hard to turn after the tiny amount of play. Is this normal? How difficult should it be to turn the charger, should it be impossible or require some force but should turn a small amount. Both ski's have plenty of power and both of the chargers feel identical.

Thanks

 

[Michael211_2000]

Don't play with that you'll go blind man!!!! :lol:


Mine doesn't have any play in it, and it's so stiff I can only barely turn it with all the finger force I can muster. It's not impossible, just close to it! If yours have slack/play in them, that would concern me... sounds like excessive wear in the drive gear, at a guess. How old are they, how many hours are on your PWC's, and have the SC's had their 100 hrs rebuilds?

- Michael

 

[drtyhatch]

Hey micheal, these are the ski's I was talking with you about the other day. We were checking to make sure that we didn't have a problem with the washers. We didn't want to have to pull the engines. They are due for rebuilds but wanted to make sure that we didnt have any additional work to do. From the sound of it, it seems like we haven't lost any washers just time for their rebuilds. They both have the same amount of play, 1 or 2 millimeters to the left or right and then it is extremely stiff after that.

 

[Michael211_2000]

IC. It's difficult to keep track when people start new threads on their same issue.

Yeah they both need rebuilding then no doubt. Sounds like your washers are intact or else you'd be able to turn the air impeller's round-n-round... this slack you feel is just excessive gear lash (probably worn drive gear on the end of the Supercharger).

- Michael

 

[red2blue]

A tiny bit of movent from the wheel is normal...it's the play in the gear.

I've missed the previous discussion here...but if you're gonna rebuild...go with the '08 upgraded shaft ect.

 

[Michael211_2000]

Mine didn't have any that I noticed when I last checked it at 71 hrs only 2 hrs after I changed the cermic washers for steel ones. I'm at 74 hrs now.

- Michael

 

[Dennis]

A small amount of backlash in the s/c gearing is normal. :cheers:

 

[Michael211_2000]

Mine's abby-normal then. LOL!

- Michael

 

[toddslightning]

i got a question why are ur seadoo super chargers so hard to turn... i dont think any blower should be like that ... my supercharger on my truck from factory ( ford Lightning ) will spin with the belt off and it to will move slight side to side ... maybe im missing sumthing with boat blowers but this is my second lighnting and i kno how car blowers are sopose to be

 

[Michael211_2000]

Well I can't say for certain, but I believe it's the slip clutch design... sitting cold, the clutch slip washers have alot of force holding them against the drive gear. However when running, hot engine oil is being sprayed at the supercharger assembly, so the clutch slip washers are being covered in hot lubricating oil... I think they slip alot easier then, though there's no way to test this theory. I have read that BRP does NOT recommend using full synthetic oils in their 4TEC supercharged engines because the full synthetic oil makes the clutch slip washers slip constantly, burning them up in time.

Anybody else got any thoughts on this subject? I too have wondered just how these things slow down when there's a sudden engine rpm drop, why they don't just blow the air hose out instantly... they must slip easier when the engine is running than when it's cold not running is all I can figure.

- Michael

 

[toddslightning]

well wut ur saying is there is oil lines running to it? thats not how my truck works at all and i kno most alll supercharger run the way mine does on my truck that are from factory ... my blower has self contained oil in the snout ... then there is a intercooler sitting in the center of the motor under the blower to cool air before it enters the heads... my intercooler is water to air also ... there is a pump that circulates the water so basicly my system has nothing to do with the other ... thats how i see most blower set up runs .. now like i said i dont kno seadoo but a blower thats hard to turn to me sounds like a problem ... its liek a turbo that dont spin also is a problem everything is build basicly the same out there

 

[red2blue]

The sc shaft...is gear driven. The clutch washers are there to save the sc wheel from the unexpected load of the boat re-entering the water (after jumping a wave for example) after it's been w/o a load (ie, when the boat was in the air). the wheel spin at roughly 50K rpm at wot....lotta momentum to compensate for when the drive line comes suddenly back under load.

Synthetics, I'm told are fine....as long as there are no friction modifiers in it. Any oil...safe for motorcycles with a wet clutch...work just fine...for a lot less money than that BRP oil the stealerships push.

Personally...I've been using Valvoline 10-40 4stroke motorcycle oil in my ski for years.$5 a quart intead of the $22 my local "deal"er wants to sell me.

 

[red2blue]

a turbo is exhaust gas driven...not the same as our sc's

 

[Michael211_2000]

well wut ur saying is there is oil lines running to it?

Nope... it's all internal. No outside lines. Oil from the engine's oiling system is sprayed onto the spinning SC shaft inside the engine. I believe when the slip washers have hot oil being sprayed on them that they likely slip alot easier than when the engine is sitting cold. I've never thought to pull the SC air hose right after running the engine to see if it's easier to turn the air impeller or not... I'd think it'd be easier to turn then though.

ps. Note that we can turn the air impeller by fingertip, it's just very very stiff and we can only get our fingers inside there to try to turn it. If you could get a wrench in there on it you'd find it not nearly so stiff with the leverage a wrench would give you!

pps. A supercharger is not driven the same way a turbocharger is... turbos can be spun easily by hand when the engine is cold, as there's no direct link to the engine's drivetrain. I used to have 2 Peterbilt trucks with 3406B CAT engines that had turbo's on them, I know quite a bit how those things operated (and how they failed, usually every 4 years or so I'd have to replace them when the bearings burned up internally and they locked up).

- Michael

 

[drtyhatch]

So is it safe to say that since the washers are to slow this charger down that jumping waves and wakes would cause the ceramic washers to wear more quickly?

 

[Dennis]

Yes, that statement is safe to say.
As far as toddslightning comparing ford truck blower to seadoo blower: the truck blower is belt driven therefore if you remove the belt it spins freely. The seadoo blower is gear driven therefore if you remove the gear it would spin freely. Hope this helps. :cheers: