'03 MCS 60,000 Miles...Well, I went OEM replacement for my bypass valve, (drivability) Here is the stock 2003 MSC Bypass valve and its $0.20 failure. The first thing I did when I got my OEM valve from Classicmini (thanks Jayson) I held it up to the light, yup you could see a corona of daylight, of course I wanted to know how much it would leak by...(no you cant blow any air past it ) Replacement was relatively easy about 1.5 hours, very cautious about the plastic inlet tube tab. All my power was restored, after replacing the belt, IC bellows(Alta)plugs (Beru...Thanks Outmotoring)and wires (oh yes #3 Corrosion on coil, for another post), this spring caused all my woes. Hey MINUSA....This should be a TSB!!! I have NEVER seen a diaphragm spring break. (and my other car is a FIAT)

 

Woh thanks for the photos SeanKidd! Glad your MCS is singing again!

Jeremy

 

just done mine she whines again wooohooo

 

How noticable were your power losses? I guess a boost gauge would show a drop and be good diagnostic value?

 

power loss was huge it was like i was driving my old cooper again ,sluggish pull away erratic power surges it was horrible ,and a very very quite supercharger , im pleased with upgraded version now i need a pulley reduction for more grunt

 

The spring failure caused the butterfly to close maybe 50%, but that does not mean half boost. Boost guage is next satisfy my paranoia, I hav NAV so Boost will need to go in the vent, but since Presure is inversely proportionate to temperature, there will be an error, maybe one of those scangauge displays is the answer.

 

i'll pass jayson the thanks. bet he'll be happy to know he was able to help