Blower snout cause boost leak???

silversc90

Registered User
If the blower snout is leaking could you loose boost out of the snout?????? I cant even push 10lbs now and I have a lot of sc fluid sitting on the inner side of my sc pulley right under the snout.
 
Everybody's looking at this but no one is posting. Logic tells me no, cause if it was. then SC fluid would be all over INSIDE of the SC, intake Inter Cooler, Tubes, etc. Maybe in an extreme case, but I don't think so. Need a SC expert to chime in here....
 
It is everywhere inside the intake tubes, at the bottom of the I.C., and on the little snouts where the vacuum lines attach. Keep in mind this is internally not in the engine compartment, it only seeps out at the sc pulley.

And I can only muster 9psi of boost when I used to get 10+.
 
umm..

I don't see that happening. That snout is not pressurized or anything. I dont' even think its open to the rest of the supercharger. Its probably sealed off.
 
i think it is possible. if a seal goes then you could have a boost\vacume leak. lose a seal on a turbo and suck the oil right out of the crankcase. i have not had one of these blowers apart yet so i do not know for sure.
 
The oil in the intake system is engine oil as stated above through the PCV. Oil behind the SC pulley would be where the SC snout seal leaks and will smell different. The SC snout only holds about 6oz. of fluid and is sealed off from the rest of the SC and engine. You can replace the seal by removing only the SC pulley.
You are not making boost b/c the oil is leaking on your belt and it is slipping as you go into high rpms. So you'll need a new seal and belt.
Good luck
 
I'm going to say yes

.....to positive pressure inside the drive unit ...as I think I understand it ...as the supercharger oil gets hot it expands
...creating pressure inside the snout...(go ahead pull the filler plug when it's hot... if you want a big mess )..this inturns put's pressure on the seals on the rotor shafts ...to aid in sealing them ..since there is no spring ...in the 2 way seals ...to help seal it to the shafts ...and blower pressure closes(seals) up on the other side ..once the snout seal goes ...pressure drops on the rear seal and is only sealing under positive pressure on the blower side... for awhile

leakage is caused....from positive and negative pressure.. since the seal is only half working on one side ....so yes it's going to suck it into the intake... negative pressure (vacume)and it blow it out the snout ....positive pressure (boost)...how much boost is lost out the snout ..no idea.... there just isn't enough back pressure to build the boost up with.....inside the blower ..dave
 
SC leak

My origional SC was leaking internally first then the snout started.I was burning alot of fluid through the motor.Take a look at one of your plugs and it will really look screwed up if you're burning much.
 
It is possible

The first supercharger on my 89 blew the seals behind the internal drive gears in my supercharger through much research I found out they are called teflon coated dual radial lip seals,say that 10 times fast, and yes they can wear out and yes oil can go in the pressure chamber and yes boost can go in the oil chamber and no you cannot buy replacement seals you can however send it to magnuson products and pay them a grand to rebuild it.
 
Yes you can lose some boost through the snout. Mine is overdriven about 23% making about 17 pounds of boost max and had a cronic problem with the snout seal leaking and spraying the entire engine compartment with a mist of supercharger oil. When this happened I would lose about 1-1/2 to 2 psi.

Apparently the seal and needle bearings that seperate the gear oil case from the rotors when worn will allow boost to enter the gear oil case and trap it there. Even after sitting for several days there was enough air pressure trapped to shoot the fill plug half way across my garage. I even experimented with a pressure relief valve and standpipe screwed into the fill hole to allow any pressure over 5 psi to excape. This turned into an even bigger leak, because once I provided a path for the boost to go, it leaked even more and took the oil with it, drenching the engine bad enough to make the headers smoke when the oil drops hit them.

I nearly cured the problem by installing a newer set of rotor and gears, but after a few months the case pressure began to push on the snout seal hard enough, that the flimsy retaining ring would be pushed out of the retaining groove and the seal would then move forward enough that the back side of the pulley wore a hole in it and allowed oil to spray everywhere.

Charles Warner supplied me with a heavy duty snap ring to replace the stock flimsy bent wire that keeps the seal in place. That seems to be holding up for the last 6 months, but it's still trapping case pressure high enough to launch the fill plug.

David
 
silversc90 said:
If the blower snout is leaking could you loose boost out of the snout?????? I cant even push 10lbs now and I have a lot of sc fluid sitting on the inner side of my sc pulley right under the snout.

my snout leaked and i could barely produce boost. rebuild the supercharger. right now take the belt off the SC so your SC doesnt run with low oil. look on eBay for a rebuildable core, in fact i am selling one right now! http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&category=33741&item=2429031312

or get a rebuilt SC on eBay, this was you will only have about 1-2 days of down time with your car, removing and installing the new SC. then sell your old sc on eBay as a rebuildable core.
 
I'm experiencing this now. I have boost making it into the oil chamber and causing oil to push out thru the nose seal.

When you finally think you've got the build done, you get a nice surprise like this one.

So, what are my options, a new rotor pack? What's that new rotor pack for the GM's I've been reading about. Anyone try it? Do we have a good place to purchase a rebuild without spending more than 600$ ?
 
I know it may seem like alot but the mp rotor pack will fix your problem and help you pick up a couple psi and reduce temps. any other way you go will be close to as expensive. Or you can keep putting used rotor packs in it having the same problem. You will also neet to replace the snout seal and prob the sc coupler that connects the snout to the sc
 
I'll probably end up going that route or getting one from ZZ performance.

I thought for sure we had someone rebuilding these with new seals and bearings for half that price. Maybe I'm wrong...
 
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the ones from zzp are the old coating and it is junk. It will start pealing after 30000 miles in some cases. The coating on the new rotors cools intake temps and it adheres to the rotors kind of like powder coat. Eaton didnt rough the surface on the gen 3 rotor pack when they manufactured them and they then coated it with a teflon like coating that hardens and flakes off easily.
 
I'll probably end up going that route or getting one from ZZ performance.

I thought for sure we had someone rebuilding these with new seals and bearings for half that price. Maybe I'm wrong...

minichopper i think is the guys name on here that was rebuilding them.
 
So I did some investigating over at ZZPerformance

They sell NEW rotor packs with the Gen 5 coating for $450.00

They'll also move the dowel pin for $10.00

Total = $460.00

I've been in touch with their customer support today and they've confirmed all my questions.


It's a no brainer, ZZPerformance sells NEW and Magnum Powers clearly indicates theirs are rebuilt. Not to mention, a saving's of close to $200.00. Oh and ZZ doesn't require a core.

Now, don't get me wrong, I would rather support an SC specific vendor any day of the week but...
 
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