BNR S3 exhaust housing bolts backing out/breaking/leaking thread

[UnknownSuperhero]

@Caligula;

You had this problem no?

[Caligula]

Originally Posted by UnknownSuperhero @Caligula; You had this problem no?

Sure did! Ill get to this in a minute or two.

[himurax13]

Originally Posted by UnknownSuperhero @Caligula; You had this problem no?

Who hasn't?

[Bryan@BNR]

If I don't hear about potential problems, I don't know how to fix them. I have been in business for 12 years doing nothing but custom turbos. I have never had issues with bolts in compressor housings stripping out. I am not saying there won't be a first .

When people do boost leak test and they see some air bubbles coming from around the bolts on the compressor side, what they think is to tighten the bolt. So they tighten, and tighten and ofcourse it strips out the threads. There aren't O rings or sealant on the bolts to prevent some seapage.

Now I can put longer bolts in the compressor housing to give it more bite into the housing, but the bolt end goes into the volute of the compressor housing causing a disturbance in air flow.

If you have a stripped out thread on the compressor housing, you can either:

A) tap the hole with M8 by 1.25 tap and use a M8 by 1.25 12mm-14mm Length bolt.
B) drill out the housing for a M8 by 1.25 Heli coil
C) If you don't have the knowledge or skill, I would love to help you fix the problem

So if you guys have problems, call me. This type of feedback is needed to update and improve my future products.

Bryan@BNR

[MPS_Fan]

Originally Posted by Bryan@BNR If I don't hear about potential problems, I don't know how to fix them. I have been in business for 12 years doing nothing but custom turbos. I have never had issues with bolts in compressor housings stripping out. I am not saying there won't be a first . When people do boost leak test and they see some air bubbles coming from around the bolts on the compressor side, what they think is to tighten the bolt. So they tighten, and tighten and ofcourse it strips out the threads. There aren't O rings or sealant on the bolts to prevent some seapage. Now I can put longer bolts in the compressor housing to give it more bite into the housing, but the bolt end goes into the volute of the compressor housing causing a disturbance in air flow. If you have a stripped out thread on the compressor housing, you can either: A) tap the hole with M8 by 1.25 tap and use a M8 by 1.25 12mm-14mm Length bolt. B) drill out the housing for a M8 by 1.25 Heli coil C) If you don't have the knowledge or skill, I would love to help you fix the problem So if you guys have problems, call me. This type of feedback is needed to update and improve my future products. Bryan@BNR

Do you also have a solution for stripped threads on the exhaust housing (Ex housing to CHRA Bolts)? There is no space for bigger holes or helicoils

[Caligula]

Okay my 2 cents... sorry for the late reply.

I bought one of the earlier units which didn't have the retaining tabs (is this the correct term?) installed by BNR @ the shop. After putting on a few thousand miles everything seemed to be going okay until I noticed a slight noise from the engine bay that sounded like a small exhaust leak. Long story short, I was unable to find the source of said leak until one day the CHRA bolt completely backed out. At that point my car sounded like an air-cooled VW under boost. It also made the leak rather easy to pinpoint, lol.

I hit up Bryan@BNR via AIM the next day, and informed him of the issue. He promptly send out a package with 6 CHRA bolts, as well as those retaining tabs to keep them from backing out again.

On that note, installing said replacement bolts/retaining tabs is a major PITA if you are trying to not remove the turbo. I had to loosen/unbolt my DP, V-band adapter, oil return line, and turbo mani to get to the bottom two bolts (FML)... and this was with the aid of a lift. Of course I also have an MS6 which doesn't help at all.

I've easily doubled the number of miles on my BNR (at much higher boost levels) since first noticing the issue, and I've yet to see any additional problems, so it would appear that the "fix" is legitimate.


@Bryan@BNR;

A. Why no lock washers on these bolts?
B. Will there be any deals for customers that want to trade in an older S3 unit for the new version once it comes out?

[mczimer]

Anything we can do as preventative maintenance on this issue?

[Caligula]

Originally Posted by mczimer Anything we can do as preventative maintenance on this issue?

Install said retaining tabs and/or tighten the bolts.

[Karmat]

As someone installing a brand new BNR what should I be doing?

I'm slightly thick so can someone point me to a link with the kind of bolts/washers I should be using?

[kish89]

It seems that after 8+ months of using my BNR, one(or more) bolts holding the exhaust housing have backed out.
I can hear exhaust leak from around the turbo and I'm 99% sure that bolt near coolant line is missing (more on this tomorrow).

Which bolt is ok to use?
M10x1.5 but what length?

[MPS_Fan]

Bolts are M6!! And length is 10mm!Write Bryan an email, he will send you a fix!

I'm still waiting for my fix package, because it was sent to wrong country

[kish89]

Originally Posted by MPS_Fan Bolts are M6!! And length is 10mm!Write Bryan an email, he will send you a fix! I'm still waiting for my fix package, because it was sent to wrong country

It's my daily driver and I need some quick fix, so I'll try to find matching bolt in local hardware store as temporary fix, because car is farting like crazy

What thread pitch do I need, is 1.0mm ok?
So M6 x 10mm length x 1mm pitch ?

[MPS_Fan]

Sorry I took a look again, bolts are M5 NOT M6!!!!
Pitch is 0.8mm and thread length is 10mm!!

And don't drive with that leak. It could fry your coolant hose!!

[kish89]

Originally Posted by MPS_Fan Sorry I took a look again, bolts are M5 NOT M6!!!! Pitch is 0.8mm and thread length is 10mm!! And don't drive with that leak. It could fry your coolant hose!!

I have stock coolant hose (hard line) so I think I should be ok.
Hopefully local hardware store is carrying that kind of bolts.

[kish89]

@Lex; here is my report

Username: kish89

Mileage on BNRS3 turbo: ~15k miles

What was the failure (which bolts backed out, broken, other?):
Bolt which is holding exhaust housing (nearest to the coolant line) backed out completely.

Boost level you are running:
20-22PSI

Are you using the bottom supporting bracket bolted to the block?:
Yes

How is the car driven (street, hard, tracked, etc):
Street, Daily Driver

Did you retorque the exhaust bolts at any time prior to failure?:
No

Does your turbo have any locking washers on these bolts?:
No

How did you fix it?:
As temporary fix, I bought M5x0.8x10mm bolt at local hardware store

[dawgincustoms]

Dawgincustoms
6000
all bolts backed out and 2 fell out. The top firewall one and front middle engine one.
23-24lbs
NO
Car is drivin extremly hard
Yes at 500 miles for heat cycle and again at 2000 miles
No
Trying to figure that out now. Motor is coming out now.

[Bryan@BNR]

Remember, just give me a call or an email if you need some plates and bolts. Also need to know your bolts size. I changed from 6mm to 5mm a while ago and didn't document when the changeover was. The 5mm thread pitch as an 8mm head. The 6mm thread has a 10mm head.

Bryan@BNR
205 640 1193
BNRsupercars@aol.com

[Lex]

Originally Posted by Bryan@BNR Remember, just give me a call or an email if you need some plates and bolts. Also need to know your bolts size. I changed from 6mm to 5mm a while ago and didn't document when the changeover was. The 5mm thread pitch as an 8mm head. The 6mm thread has a 10mm head. Bryan@BNR 205 640 1193 BNRsupercars@aol.com

@Bryan@BNR; I noticed you have new compressor housings on the BNRs. Can you please give us some details on the changes?

[himurax13]

Originally Posted by Lex @Bryan@BNR; I noticed you have new compressor housings on the BNRs. Can you please give us some details on the changes?

I have pictures. I didn't notice any difference except for the vacuum line nipples.

Sent via blown passenger side speakers.

[DSIT995]

New housing and wastegate.. will upload more pics later

tapa tap tap

[MPS_Fan]

More pictures please. Exhaust housing is still the old one? Could you measure the compressor inlet size?

looks like Bryan prefers now 2 port boost contro model, since wastegate has now 2 nipples.

[DSIT995]

ImageUploadedByTapatalk1374191155.671298.jpgImageUploadedByTapatalk1374191170.176807.jpgImageUploadedByTapatalk1374191182.096982.jpg

Some more shots of the updated s3... Question for everyone with the newer version.. How did you plumb the wastegate to ebcs in 3 port mode? Does one of the ports need to be plugged?

[himurax13]

Wow, that housing is different than the one my buddy bought in May.

[meelo88]

Humm here is mine from April...



Very interesting...

[DSIT995]

Originally Posted by himurax13 Wow, that housing is different than the one my buddy bought in May.

I gotta check for a restrictor pill in one of these ports... I'm a lil lost on how this would set up with a 3 port ebcs

[silvapain]

Same way you do it on a K04... Cap off the bottom port on the WGA.

[bstover17]

Damn that new housing looks nice. Hopefully this issue will be fixed before I order mine.

[Lex]

Originally Posted by DSIT995 Some more shots of the updated s3... Question for everyone with the newer version.. How did you plumb the wastegate to ebcs in 3 port mode? Does one of the ports need to be plugged?

What about the top port of the WG? Take a look in all the ports carefully to find the restrictor because only then I can tell you how to best plumb it.

[faeker]

Originally Posted by bstover17 Damn that new housing looks nice. Hopefully this issue will be fixed before I order mine.

Edit: nevermind saw it in second look

sent with smiles and mouth hugs

[ledfootrob]

Yeah I just received mine today and got the new housing. Interested to see how to hook 3 port up with this before install next week.

[TiGraySpeed6]

Here's another pic- I'm not aware of any restrictor in line, it would still have to be added if using the stock EBCS

Bryan's just set it up to mimic the OEM configuration and use the stock EBCS !as long as a restrictor is used between the source and the WGA!.
For those doing that the path becomes
source>restrictor>WGA lower>WGA>WGA upper>Stock EBCS>TIP

For using an aftermarket 3 port EBCS, like Cobb's or any of the similar units, the easiest thing to do is to block the lower WGA port, then plumb it following the instructions included with the EBCS, which are, generically,
Port 1 - vent - connect to TIP/TIH
Port 2 - action - connect to WGA
Port 3 - source - connect to full pressure boost source

[TiGraySpeed6]

To have confirmation direct from the source I emailed Bryan and asked about resitrctors and plans regarding the 2 port WGA.

He replied that there is not currently a restrictor in place, but that there will be "in the next batch"

Take from that what you will...

My next batch will have the restrictor... Bryan Nickell Owner of BNR Supercars LLC (205)640-1193 bnrsupercars.com From: Eric To: BNRsupercars@yahoo.com Sent: Friday, July 19, 2013 12:25 PM Subject: Mazdaspeed question about new 2 port WGA Hey Bryan, Just wanted to know if you've added any restrictor pill or anything to go along with the new style 2 port WGA for the Mazdaspeed BNRs3? Eric-

[Lex]

It will be tricky with an added 1 size fits all restrictor - hope he does a good amount of testing. This is why I came up with the Boost Dial since different intake and exhaust setups can benefit from a tunable restrictor.

[TiGraySpeed6]

I'm surprised he's adding one at all. I like Bryan, and the S3, but I doubt he's done much testing, at least not the way you think of it Lex.

[Ziggo]

@Lex;

Well mine finally backed out.

Mileage on BNRS3 turbo: 33 months - ~30k Mi
What was the failure (which bolts backed out, broken, other?): Bolt appears to be backed out.
Boost level you are running: tapering up to 25psi
Are you using the bottom supporting bracket bolted to the block?: Yes
How is the car driven (street, hard, tracked, etc): Tracked in the first year, but not since. Some drag usage
Did you retorque the exhaust bolts at any time prior to failure?: I sent out my hotside for coating and then reinstalled it and retorqued all bolts prior to installation. Torqued by feel, don't have a box end torque wrench.
Does your turbo have any locking washers on these bolts?: No (lockwashers don't do shit anyway, see NASA RP-1228)
How did you fix it?: Not fixed yet. Intend on pulling the turbo and then safety wiring bolts



Confirmed my bolts have the 10mm head. Going to order replacements and safety wire them in with nickel\chromium wire. No more messing with it.

[JgamB]

I don't see the crimped brackets on yours Zig that would only allow for 1/16 of a turn at most before metal on metal. Am I missing something?

[Lex]

Looks like eventually all the BNRs without the locking washers or safety wire will see the bolts backing out. This is something that someone installing a used BNR should do before putting it in.

[phate]

Originally Posted by Ziggo Does your turbo have any locking washers on these bolts?: No (lockwashers don't do shit anyway, see NASA RP-1228)

Just skimmed through that - sweet reference manual.

[Ziggo]

Originally Posted by JgamB I don't see the crimped brackets on yours Zig that would only allow for 1/16 of a turn at most before metal on metal. Am I missing something?

I was a very early adopter, no crimped brackets for me.

I am not a huge fan of the crimped bracket solution. It works so the bolt can't back out completely, but I consider any rotation of the bolt a joint failure due to the loss of preload. At the end of the day, if it's a critical joint you safety wire it. The only reason not to is the time it takes, but it will take less time than if I have to pull the turbo again to fix this. Should have done it the first time round.

Sent from my SAMSUNG-SGH-I747 using Tapatalk

[Ziggo]

Originally Posted by phate Just skimmed through that - sweet reference manual.

Its the best publicly available guide, but keep in mind it's nearly 25 years old. The plating and materials section is pretty dated. Some of the plating has been discontinued due to health concerns (mostly containing chromium or cadmium) and there are a ton of new fancy thread lubricants and bolt materials on the market now.

If you can learn everything else in there though you will be better than almost every engineering student coming out.

Sent from my SAMSUNG-SGH-I747 using Tapatalk