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-   -   Innovate Owners - BE CAREFUL! (https://www.ft86club.com/forums/showthread.php?t=45393)

swift996 08-27-2013 11:01 PM

Innovate Owners - BE CAREFUL!
 
Sorry to make a whole post but thought it would be worthwhile for anyone owning one to check the fitting that feeds air/vacuum to the brake booster. The grey plastic one. I was on the track at VIR and had my pedal drop to the floor (pretty scary but fortunately was at a sort of slower part of the track).

Mine some how came slightly loose and the brakes could only engage at about 10% until you pumped the brake hard a few times and then again the pressure would leak out.

If I were on the straight there (hitting about 130mph) I would have been into the wall and totaled my car.

I did a temp fix where I just slapped some lock-tite all around it and turned it as far as it would go. I plan to take it off and inspect it since I'm back from the track.

mad_sb 08-27-2013 11:04 PM

scary shit man.

F1point4 08-27-2013 11:13 PM

Hey Mr Swift,

I'm glad you are okay. Hopefully you can fix what ails your baby. Do you have to buy a new seat from the pants wetting you may have done?

Regards,
The man who takes photos.

sw20kosh 08-27-2013 11:23 PM

Thank you for the heads up!

Is this the 90 deg hose fitting? I am confused at how a small leak from there could cause the brake booster to fail. The vacuum level in the manifold is not going to fall sufficiently low due to a tiny leak right? I don't know to much about how the brake booster works though...

swift996 08-27-2013 11:59 PM

Quote:

Originally Posted by sw20kosh (Post 1171820)
Thank you for the heads up!

Is this the 90 deg hose fitting? I am confused at how a small leak from there could cause the brake booster to fail. The vacuum level in the manifold is not going to fall sufficiently low due to a tiny leak right? I don't know to much about how the brake booster works though...

Yes the 90 degree one. I'm not 100% sure how it works. I had someone sit in and apply the brakes when I moved the fitting freely to the left he said the pedal lost all pressure and it firmed up when I went to the right with it.

NickFRS 08-28-2013 12:36 AM

Crazy! Good thing the drift gods invented the E-brake.

nonicname 08-28-2013 08:39 AM

WTF how is this kit messing with the brakes?
:needpics:

swift996 08-28-2013 08:42 AM

Quote:

Originally Posted by nonicname (Post 1172470)
WTF how is this kit messing with the brakes?
:needpics:

Read above, there's a fitting that pumps air to the brake booster which pressurizes your brake master cylinder.

There isn't really a pic worth taking just that my fitting was able to move left and right freely.

wparsons 08-28-2013 08:51 AM

Quote:

Originally Posted by swift996 (Post 1172473)
Read above, there's a fitting that pumps air to the brake booster which pressurizes your brake master cylinder.

There isn't really a pic worth taking just that my fitting was able to move left and right freely.

Uhhh, the brake booster runs off vacuum, not positive pressure. Without vacuum the pedal would go really hard, not really soft. Proof of this is what the pedal does with the engine not running (0 vacuum), it goes really hard really quick.

For safety, I would re-bleed all four brakes before driving it again. It sounds more like air in the system than something caused by a loose vacuum fitting.

nonicname 08-28-2013 09:42 AM

well I don't know what the brake booster is.
This is why I'm never the first to buy anything. way too many bugs going on
ALWAYS.

swift996 08-28-2013 09:57 AM

Quote:

Originally Posted by wparsons (Post 1172477)
Uhhh, the brake booster runs off vacuum, not positive pressure. Without vacuum the pedal would go really hard, not really soft. Proof of this is what the pedal does with the engine not running (0 vacuum), it goes really hard really quick.

For safety, I would re-bleed all four brakes before driving it again. It sounds more like air in the system than something caused by a loose vacuum fitting.

I'm going to fully bleed them again. I did twice at the track until I got no bubbles. Not very familiar with how the vacuum pressure works but when I loosened the fitting by rotating it left the pedal lost pressure (car running).

Z-PDX 08-28-2013 10:18 AM

Quote:

Originally Posted by swift996 (Post 1172582)
I'm going to fully bleed them again. I did twice at the track until I got no bubbles. Not very familiar with how the vacuum pressure works but when I loosened the fitting by rotating it left the pedal lost pressure (car running).

Curiouser and curiouser. I can't imagine a scenario where loss of vacuum would cause the pedal to go to the floor.

As posted above, it would normally go hard. Going past its normal travel would normally indicate something in the hydraulic system, such as excessive heat or air.

Please keep us all posted.

mad_sb 08-28-2013 11:21 AM

so, i'm starting to think maybee you boiled the fluid AND have a vacuum leak on the booster. When the booster is NOT under vacuum, you have a firm pedal due to no vacuum assist, when you do have vacuum on the booster you have sponge pedal due to the bubbles in the fluid.....

Bleed them again for sure.

xjohnx 08-28-2013 11:36 AM

What kind of brake fluid were you running?


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