blow off valve gasket boost leak

[gats0101]

I boost leak tested my car and I have a small leak at the blow off valve gasket. I bought a new gasket and applied some RTV to it and it still leaks. Any suggestions? I have a new gasket coming but was looking for some input on fixing this leak.
thanks

 

[Silver 95 GST]

Are you sure it's the gasket? Spray some soapy water on it and boost test again.

 

[noonan98turbo]

Like silver 95 gst said, spray soapy water on it and look for bubbles indicating a boost leak. The gasket could be fine and it could be leaking somewhere else. Normally a new gasket alone is good enough but you applied RTV also so you should be fine. What kind of bov do you have? I have a greddy type-s and I had to really make sure I tightened the nuts holding the bov to the intercooler pipe down as tight as I could get them. Let us know how you make out.

 

[jongreene]

a. not tight enough.
b. gasket.
c. one or both of the flanges arent totally flat.

 

[DougR]

Im assuming since you said, you bought another gasket. you are refering to a 1g Bov flange gasket.... If so the Pipe flange or BoV base is warped or scratched....

Remove the BoV and Pipe and sand the flanges with 400 grit wet sandpaper... Either use a rubber sanding block. Or something FLAT that you can wrap the paper around...

Within just a few motions you will Quickly see if and where the flange is warped. IF you Must do the BoV base.. Shove some rags into it to keep the metal shavings from entering the BoV. Do this at you own risk! nd beshure to Clean it completly before reinstalling...!!

Basicly make shure Both are nice and flat. with as little deviation as possible.. I sanded mine on a granit table here at work till they were both Glass smooth and flat.

BTW overtightening these flanges will result in Warped flanges... Tighten it just enough so that it will not come apart.. you dont need to put Hulk strenght on it...

 

[gats0101]

Thanks for all the replies guys, I won't be able to mess with it till this weekend so hopefully I'll get it figured out.

 

[knochgoon24]

I just used blue RTV, let it cure the FULL 24 hours, and no gasket. I haven't had any problems with it.

I didn't tighten it all the way down until after it had dried. I made it tight enough that it was just touching the flange, but when I went back and tightened it after it dried, I was able to turn the bolts another half turn or so.

 

[kenamond]

First, do as was recommended and break out your BLT spray bottle and make sure it's leaking where you think it is.

If the gasket surface of the metal flange of the IC pipe was painted (assuming aftermarket UICP or aftermarket paintjob on the stock UICP), take the paint off with paint thinner...same for powder coating. If you're careful, you can take it off almost out to the edge of the "football" so that it still looks purdy from the outside. Then use enough RTV on both sides of the gasket to fill any gaps due to warped flanges (but not so much that when you assemble things, blobs of RTV don't drop into the IC pipe), let it set up, then tighten it a bit more (as was recommended by knochgoon24). Might be that the paint/powdercoat is separated from the metal flange and the air is leaking between the paint and metal...which gaskets and RTV won't help since they're between the paint and BOV flange.

 

[sparco431]

ok im having a similar problem. im almost positive i have a boost leak. and im about 50 percent positive its at my bov. how do i test where the leak is coming from? i dont get the soapy water thing. someone please explain

 

[Fastclipse97]

rtv as a temp solution is ok, but what is the possiblity of some rtv on the other side of the flange getting into the intercooler pipe?

i would drive easy, and replace the gasket as soon as you get it

to test with soapy water

put some soap in a bottle and add water, use sprayer to spray soapy water over intercooler couplers and bov flange.

if there is a leak you will get bubbles at the leak

 

[kenamond]

RTV is fine for making sure your BOV gasket seals. My flanges aren't warped, but I still put RTV on both sides of the gasket. Mine hasn't ever leaked since I put in on (with RTV) years ago.

As far as soapy water, you have to do this *while you're doing a boost leak test*. If you don't know what a boost leak test is, go search how to do one.