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Symptoms of a boost leak????

T
Apr 17, 2010
78
15
8
Hello, i finally got my Iqr with a 2012 cfi 800 engine back together to took it for a test/break in ride. It has a 2013 bullydog silber turbo on it, the first few pulls went perfect and then randomly i get a wot stutter....let off the throttle and hit it again and revs out great.....few more times no issues and then again itll stutter almost sounds like its bouncing off of a rev limiter. Max rpm ive seen was 8200... today i pulled the blow off valve and found that i can blow air through it and it wasnt sealing. I cleaned it and applied some lithium grease to the orings. Im guessing that was the issue i was having when the boost was escaping the bov??? Anyone else have any issues with the silber bov? Of course it got to be really warm today and all the snow melted so i gotta travel to test it out now.....Thanks!
 
P

purepolaris600

Well-known member
Aug 21, 2009
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Elkader iowa
You should be able to blow air threw it, the blowoff valve is held closed by boost pressure. If you have a boost leak you will be slow to build boost and might only be able to build a few pounds. Bet way to find a boost leak is cap turbo intake and exhoust downpipe and add air with a compressor to wastegate hose on turbo compressor l, then just listen or what I do is spray soupy water everywere.
 

Wheel House Motorsports

Well-known member
Lifetime Membership
Nov 27, 2007
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SW MT
Just cap the exhaust outlet and turbo inlet and add pressure. There is no substitute for checking. Depending on where leaks are, be it intake or exhaust side you can have all sorts of dumb issues, be them small or large. Especially on a build like this that is 1 off. Check everything, its too easy not too.
 
R

roni87

Well-known member
Feb 11, 2011
513
213
43
I Falls, MN
Just put an external kit on mine...does same thing and really sure it's over Rev issue. I'm weighted to the max and changed to weaker secondary spring.
2015 external gate
1100 feet, 7psi spring
Rktek rev2 12.5 domes
Plugs gapped .018
81.5 grams in team weights, pink spring
44-48 helix, team black/purple spring (lighter)
60/40 av pump

Will see 8450 on tach but acts like over rev. 5 and 3 psi spring will be here tomorrow.
 

AKFULLTHROTTLE

Well-known member
Lifetime Membership
Dec 20, 2009
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Alaska
Ya mine will do a over rev sputter/popping sound as well.

Had 83 grams on 7psi and was really bad
Put 5 spring in and did it very little

Put 86 grams in and with the 7 it acted like it did with the 5/83.

I now have 86 grams 5 psi spring and does not do it anymore. On flat at 2500 feet she pulls around 8100-8200 and I say 8350 climbing.
 

Polarisrocks

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Sep 22, 2002
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Eastern Wa
Your bov has boost on both sides of the diapham, so it shouldn't leak if removed and you are blowing through it with your mouth. You don't blow more pressure with your mouth than the low boost you are running. What bov are you running?
 
T
Apr 17, 2010
78
15
8
I am running the silber turbo blowoff valve, i pulled it apart and cleaned/greased the orings and now its sealing......just have to figure out my over reving issue now....
 
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