MPI supercharger waste gate sticking

[pylon]

im not sure if its a blow off valve or the waste gate thats sticking on my buddies sled . its on an 06 apex with a stage 1 charger . its the peice that come off the intercooler and is boost activated . the valve keeps sticking open and wont shut . we took it apart and cleaned it and it worked for a little ways then same thing , just keeps sticking open . i thought of trying a small hone and honing it out ? anyone else have this problem .thanks

 

[mattymac]

Its either a blow off valve or a bypass valve. Most bypass valves stay open under LOW boost. A blow off valve is designed to open when you let off the throttle to let the "boost spike" from the throttle valves closing and no where for boost to go. There should be a spring above the valve and most have an adjustable preload.

Wastegates are always on the exhaust side and are either internal (inside a turbo exhuast housing) or external, like on the exhaust piping.

When you took it apart did the valve move freely in the housing? Can you get a pic of it??

 

[T-BO]

Thats your blow off valve. Try a heavier spring on that diaphram inside the valve to hold it shut.

 

[pylon]

k thanks for that , its a blow off valve then . it does stay open under low boost (idle) then closes up when you give it gas. when we cleaned it up it was working perfect .opening and closeing as it should have . now it just sticks open unless we take it appart and re set it . orginaly we thought it was just dirty ( as it was ) now theres something more though . do they were out? i dont know much about superchargers but have a pretty good grasp on turbos so any help with this is great thanks

 

[modsledr]

Have you adjusted it (the allen on top with the set-nut)...screw it in (clockwise) for more spring pressure.

You should hear a "hiss" sound at low throttle (just off idle cruising down the trail).

 

[nytrocharged]

take the blow off valve right off you dont need it on a supercharged i have had many sleds with supers

 

[RACINSTATION]

I have to respectfully disagree.....I would run the blow off valve on the supercharger. Cleans up the bottom end a bunch.

I like the Turbonetics blowoff valve the best.

There is no wastegate, so it has to be the blowoff.

 

[skyler@mpi]

We are now offereing a bov/bypass for out kits. For more info please call us here at MPI 888-649-4609 ext 121, Thanks Skyler