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scr8pdo
Saturday 28th August 2010, 20:09
Hi does anyone know if a manual boost controller should let any air through at all until the preset pressure is reached, Iam talikng about the brass ball and spring type mbcs, when i blow into my one, no matter how far the screw is in ie for maximum boost, it lets by, only slightly but i thought this would cause wastegate creep if this happened, its basically the ball bearing not sealing fully on the inside, i mean it very very slightly lets air through, is this normal or do i need to find a way of sealing it totally or get another mbc?
p fandango
Saturday 28th August 2010, 20:17
no it shouldn't, a bleed valve will which a lot people confuse them both

a bleed valve normally has 3 ports while a MBC has 2
scr8pdo
Saturday 28th August 2010, 21:51
no it shouldn't, a bleed valve will which a lot people confuse them both

a bleed valve normally has 3 ports while a MBC has 2

No its defo a mbc, i had a bleed valve before, it seemed to be more effective than this mbc, maybe now I know the reason why lol, maybe if i countersink the hole inside with a drill slightly i will get a better seal, otherwise its a new one, shame cause this one seems to be so well made

http://i34.tinypic.com/20a4412.jpg
Rnash2002
Saturday 28th August 2010, 22:17
Sounds daft but have you tryed to put the spring in the other way,and yes thats a mbc and not a bleed valve,ive got one just like that and its fine.
What way are you connecting it to the car?
scr8pdo
Saturday 28th August 2010, 22:35
Not on the car yet but connected up with the connection on the side going to the wastegate actuator, when i blow in from the bottom connector (one where ball seats) you can blow slightly passed the ball even when fully wound down, I even tried putting another BB on top of the spring and winding it in just to see if I could make it seal, but no matter how far or tight you do it, it still slightly lets by, I wonder if grease might help it seal a bit better?


Sorry what do you mean spring in the other way? do you mean turn it over or put it in before the BB?
Rnash2002
Saturday 28th August 2010, 23:48
Turn the spring over,when i got mine i had to do it because it would boost properly.
I will have a look at mine tomorow and see if it leaks alittle air.