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3800sc upper plenum leak by Tweeder
Started on: 01-26-2014 06:08 PM
Replies: 21 (210 views)
Last post by: solotwo on 02-07-2014 07:38 PM
Tweeder
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Report this Post01-26-2014 06:08 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
This is the second time I have replaced this gasket. Both are felpro. I sprayed carb cleaner and found a leak under the supercharger around the thermostat housing. So I replaced the gasket and its still leaking so I removed it and put a bead of silicone around the whole gasket, top and bottom. Waited a couple days for it to dry and it still leaks from that same spot. Got a new gasket and checked both mating surfaces with a square and no light comes through. I took 2000 grit sandpaper and wet sanded to remove any corrosion as it looks like its been leaking a while and its still leaking not as bad though.. I torqued the supercharger to 17ft/lbs. Any suggestions?

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Report this Post01-26-2014 06:30 PM Click Here to See the Profile for ericjon262Send a Private Message to ericjon262Edit/Delete MessageReply w/QuoteDirect Link to This Post
I know most flat surfaces have a torque procedure, where certain bolts are torqued first, in a pattern, and usually in steps, not just straight to max torque. I'm not sure whether the blower has a procedure like this or not, but it'd be worth looking into.
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MstangsBware
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Report this Post01-26-2014 06:36 PM Click Here to See the Profile for MstangsBwareClick Here to Email MstangsBwareSend a Private Message to MstangsBwareEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Tweeder:

This is the second time I have replaced this gasket. Both are felpro. I sprayed carb cleaner and found a leak under the supercharger around the thermostat housing. So I replaced the gasket and its still leaking so I removed it and put a bead of silicone around the whole gasket, top and bottom. Waited a couple days for it to dry and it still leaks from that same spot. Got a new gasket and checked both mating surfaces with a square and no light comes through. I took 2000 grit sandpaper and wet sanded to remove any corrosion as it looks like its been leaking a while and its still leaking not as bad though.. I torqued the supercharger to 17ft/lbs. Any suggestions?



R u talking about the SC gasket or LIM gasket?

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Tweeder
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Report this Post01-26-2014 06:48 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by MstangsBware:


R u talking about the SC gasket or LIM gasket?


The sc gasket

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ericjon262
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Report this Post01-26-2014 06:50 PM Click Here to See the Profile for ericjon262Send a Private Message to ericjon262Edit/Delete MessageReply w/QuoteDirect Link to This Post
have you followed a progressive torque sequence? most of the time, you start with the center bolts and spiral out to the outside bolts.
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Tweeder
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Report this Post01-26-2014 06:57 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by ericjon262:

have you followed a progressive torque sequence? most of the time, you start with the center bolts and spiral out to the outside bolts.


yeah I started with the center and went side to side alternating from right to left.

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Report this Post01-26-2014 07:58 PM Click Here to See the Profile for FIEROFLYERSend a Private Message to FIEROFLYEREdit/Delete MessageReply w/QuoteDirect Link to This Post
Is there a lot of corrosion in that area of the intake or some thing is warped in that area for it to be leaking after a gasket change. did you scrape all the old gasket material off and clean the surfaces very well. Dan
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Report this Post01-26-2014 08:08 PM Click Here to See the Profile for smartaxelClick Here to visit smartaxel's HomePageClick Here to Email smartaxelSend a Private Message to smartaxelEdit/Delete MessageReply w/QuoteDirect Link to This Post
There are little o rings in that gasket area also (if i recall properly). Those are new also?
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Tweeder
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Report this Post01-26-2014 09:15 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FIEROFLYER:

Is there a lot of corrosion in that area of the intake or some thing is warped in that area for it to be leaking after a gasket change. did you scrape all the old gasket material off and clean the surfaces very well. Dan


Yeah I cleaned it and block sanded it with 2000 wet

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Tweeder
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Report this Post01-26-2014 09:16 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post

Tweeder

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quote
Originally posted by smartaxel:

There are little o rings in that gasket area also (if i recall properly). Those are new also?


Yep they came with the kit.

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Report this Post01-27-2014 11:14 AM Click Here to See the Profile for FIEROFLYERSend a Private Message to FIEROFLYEREdit/Delete MessageReply w/QuoteDirect Link to This Post
Then most likely you have some thing warped enough to cause the leak
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Tweeder
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Report this Post01-27-2014 01:12 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FIEROFLYER:

Then most likely you have some thing warped enough to cause the leak


Yeah that was my thought that's why I took a straight edge and back lit it with a flashlight to the supercharger and intake manifold and got no light through.

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fieroaddicted
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Report this Post01-27-2014 02:13 PM Click Here to See the Profile for fieroaddictedClick Here to Email fieroaddictedSend a Private Message to fieroaddictedEdit/Delete MessageReply w/QuoteDirect Link to This Post
did u try sanding the cover on a surface plate? I had a similar issue with thermo cover on a side by side. You couldn't tell with a straight edge that it wasn't true. I did figure 8 oscillations on the surface plate and kept checking it till it was flat. No problem after that. Just a suggestion.
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Tweeder
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Report this Post01-27-2014 02:55 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fieroaddicted:

did u try sanding the cover on a surface plate? I had a similar issue with thermo cover on a side by side. You couldn't tell with a straight edge that it wasn't true. I did figure 8 oscillations on the surface plate and kept checking it till it was flat. No problem after that. Just a suggestion.
troy


No I used a small 3x5" sanding block.

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Report this Post01-27-2014 03:55 PM Click Here to See the Profile for conan469Click Here to visit conan469's HomePageClick Here to Email conan469Send a Private Message to conan469Edit/Delete MessageReply w/QuoteDirect Link to This Post
could it be the throttle body gasket?
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Report this Post01-27-2014 03:57 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by conan469:

could it be the throttle body gasket?


Nope that's new and no stumble when that's was sprayed.

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Report this Post01-27-2014 04:43 PM Click Here to See the Profile for FIEROFLYERSend a Private Message to FIEROFLYEREdit/Delete MessageReply w/QuoteDirect Link to This Post
Could it be the leaking around where the rod for the boost bypass valve goes into the SC or a possible crack some where that you are not able to see with the naked eye
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Tweeder
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Report this Post01-27-2014 04:47 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FIEROFLYER:

Could it be the leaking around where the rod for the boost bypass valve goes into the SC or a possible crack some where that you are not able to see with the naked eye


Don't thinks so but I will try that. I can only hear it stumble when I directly spray at the supercharger where the thermostat housing is. That and when I took the gasket off, that area was a little corroded and the gasket was s different color like it was saturated from the carb cleaner. I'll have to see if I can shoot a vid.

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Report this Post01-28-2014 01:01 PM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
Is it leaking Air or Antifreeze ? the only place anti freeze can leak there is the "O" rings. anything else is compressed air.
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Tweeder
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Report this Post01-28-2014 01:39 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Lou6t4gto:

Is it leaking Air or Antifreeze ? the only place anti freeze can leak there is the "O" rings. anything else is compressed air.


Not that I can tell

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Tweeder
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Report this Post01-29-2014 09:59 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
I just pressurized the intake from the throttle body and blocked off the brake boost and purge solenoid lines. I get no noticeable bubbles from around that area, but it will stumble if sprayed with carb cleaner.

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[This message has been edited by Tweeder (edited 01-29-2014).]

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solotwo
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Report this Post02-07-2014 07:38 PM Click Here to See the Profile for solotwoSend a Private Message to solotwoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by smartaxel:

There are little o rings in that gasket area also (if i recall properly). Those are new also?


Yes those little round seals about the size of a quarter can leak. You should have seen mine when 2 Seat Garage took the SC off. What a mess.
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