Leaky Crushed BOV

[xcelr8n]

Put a "crushed" 1g bov on the car a few days, did a boost leak test built 10 psi instantly with the compressor, and than would build no more because the BOV was leaking MASSIVELY, is this probably just because of a shiet crushing job, I thought the average stocker even held like 16psi.

 

[CyberEye]

Put a "crushed" 1g bov on the car a few days, did a boost leak test built 10 psi instantly with the compressor, and than would build no more because the BOV was leaking MASSIVELY, is this probably just because of a shiet crushing job, I thought the average stocker even held like 16psi.

where is it leaking from the bov? is it leaking from the actual bov, like out the vent tube, or is it leaking from underneath where it meets the UICP. If it's leaking out the actual bov, take it out and use a vac pump to check how much vac it holds/takes to open it, like you're supposed to do while crushing it.

 

[xcelr8n]

It leaks from the actual vent tube, I think this bov is just fecked, came with my upper ic pipe.. I replaced it with the stock bov, but I know that leaks at a certain point anyways.
Ive never seen a leaky bov until tonight, I can imagine that just robs power like nothing else...

 

[Quasimondo]

stock 1g bov can hold 20-23 psi. Unless you're going beyond that for boost, I don't see any reason to crush it.

 

[Below Ambient]

stock 1g bov can hold 20-23 psi. Unless you're going beyond that for boost, I don't see any reason to crush it.

ditto on that and a good point... if you check out vfaq it does have some questionable results from crushed BOV's... as soon as I see scott grey use a crushed one ill do the same..

 

[xcelr8n]

OK, well I have 2 spare BOVs in my garage, I went out and bought a vacuum pump, and crushed it properly, so that it starts opening at 18inhg, and is fully open at 20, and now I get this weird flutter from it, I dont know if its normal, sounds shitty, like the air is leaving the bov in 2 seperate times, I get dual fluttering...
I have the other one thats just totally stock as well.
Ps. Will be running 22-24psi on the evo3 this Friday, so I dont want any leaks, and this is the only one I could find so far.
Any ideas on the fluttering?

 

[Turbo Talon DL]

I have a crushed 1g BOV also, it makes a little flutter at low boost as well. The only reason I got this BOV is because it was $48 from somebody and I needed a BOV QUICK! I dont make anywhere NEAR 18 or 20in/hg tho I have HKS 264/272 and a cyclone intake mani. I have no leaks, no idle surge. My comp is good also, which means my valves are seating properly. My valve timing is correct now also.

 

[4pistons]

Try this mod http://www.thedodgegarage.com/turbo_bov_mod.html

It worked great for me after crushing didn't stop my BOV from leaking either.

Rick - '91 GSX

 

[xcelr8n]

OK, Im getting a little sick of this BOV leaking at 10psi thing going on right now....
I had 2 spares, so I put the non crushed at all BOV on, gasket is sealed tight etc, and it to only holds 10psi from the compressor before it to busts open and leaks like MAD..
Are we doing the test wrong, I popped the vac hose that attaches to the BOV off stuck in the compressed air source, opened the tb, and filled it, I build 10psi within 3 seconds, and it holds 10psi for a nice long time, but if I go anythign over 10, bov dumps it all out...
Is this method ok?
Quick help is appreciated, no point in racing Friday if I cant make more than 10psi without leaking.

 

[sweet97]

If I may add my problem I thank you. I have a built motor and a 60-1 with the stock 1G BOV. I was flowing 1400Hz right after the rebuilt motor at 18PSI. Raising the boost to 22/23 PSI lowered the flow as did loering the boost back near 18 PSI. I suspect the BOV is leaking, leaks at idle anyways. I cannot hear anything(52 year old ears!) I will try a compression test today. If Ineed/get a BOV what is the best against leaks, the TIAL? I vent to atmosphere. Thanks, Mark

Compression test showed 3 leaks. My MBC is leaing more than it should so I will control the boost with the actuator arm. An IC hose was leaking and that is fixed but the TB seals/bushings are leaking. Anyone besides the dealer sell tham? I just haven't seen them for sale but honestly have not looked over the last year and a half I have owned the car either!

 

[daren_p]

stock 1g bov can hold 20-23 psi. Unless you're going beyond that for boost, I don't see any reason to crush it.

It can hold this much boost without any leaks? Mine has about 6 months use on it & I bought it brand new & when I do a boost leak test it starts to leak at 16 psi? How can it hold that much without any leaks as some cars won't even make enough vacuum to ever open that?

 

[4pistons]

I suspect the BOV is leaking, leaks at idle anyways. I cannot hear anything

Try venting your bypass hose to atmosphere and take it for a ride. You'll definitely know it's leaking if you hear it squealing while under boost. You should only hear it when you let off the throttle. Put your bypass hose back on when you return as the car won't run very well with it disconnected but it'll let you know your BOV is leaking.

some cars won't even make enough vacuum to ever open that?

A compressor bypass valve (blow off valve) is a pressure differential valve. It activates when the pressures behind the valve are less than pressures in front of the valve by a certain amount.

The stock spring in a 1G BOV exerts about 7 - 8 pounds or pressure against the valve. Any DIFFERENCE in pressure from the front of the valve to the back that is greater than that will open the valve no matter the actual pressure. You could put 100 psi against the valve and as long as there was also 100 psi behind the valve the 7-8 pound spring would keep it shut.

Rick - '91 GSX

 

[xcelr8n]

FWIW, I did the test the proper way, no more pulling the vac line off, and I built about 18psi, and held it for 30 seconds, My stock BOV starts leaking after 18pounds though, but not a big deal, im pleased with the results.

 

[Quasimondo]

It can hold this much boost without any leaks? Mine has about 6 months use on it & I bought it brand new & when I do a boost leak test it starts to leak at 16 psi? How can it hold that much without any leaks as some cars won't even make enough vacuum to ever open that?

Have you checked to see if it's leaking through the gasket at the flange?

 

[yangtech]

i got tired of my leaky 1g bov so i went with the Tial bov and problem solve...