Broken exhaust stud (RB25DET)

[Toad[^_^]]

The header says it all. I've been chasing vacuum leaks left and right trying to figure out why my engine seems to be capped at 5000 rpm and while messing around under the hood I noticed that the nut holding the exhaust manifold to the block nearest to the firewall appeared loose. When I put a socket wrench on it I noticed that the stud was wiggling and as I removed the socket both nut and half the stud came out. Sooooo.... Where do I get a new stud? Is this even possible to find? I'll try to post a pic later if it will help anyone

[Toad[^_^]]

Holy crap!NM, answered my own question http://www.store.yahoo.com/pha....html

[JonPowell]

http://www.mcmastercarr.com has them also, individually.

Length=50MM Size=10MM Pitch=1.25

[Slo_240sx]

18 bux a stud!? YESH. I'd go with the steel 2.50 dollar ones.-Alex

[fly240]

have you got your broken stud out yet....I have the same stud same problem. this is odd that it happen the same bolt. seems that my stud was already broken 99% of it. I only use very small force and its in half. I really need helps of taking that last broken stud out....please let me know...than you

[Imissmyturbo]

I had the same thing happend to the same stud. I also have another stud break around cly # 3. I got that one out but when I put my extractor into the rear stud it broke off inside. I have been running without it for about 2 years now and haven't seen any traces of a leak there.

[fly240]

wow....so, are you using the stock exhaust manifold?....and no leaks what so ever for that last stud left out.....I will try running without bolting the last stud....hope it wouldn't leaks on me...thank you

[Imissmyturbo]

yup stock manifold no leaks. Running 15-18 psi.

[integra7]

If you need an RB25DET exhaust manifold stud.....I think I got 3 laying around somewhere because I ordered new OEM ones.. Let me know if you need it.

[Darius]

Go to your local fastener shop and you can get them a little bit shorter for $1.25 each. The nut still fits on there just fine with the stock gasket. I'm running a copper gasket so i have a little more room to play with.

[rotorimp]

You can call ARP with the specs and then you will never have to worry about them again. Make sure you torque them. BTW going cheap will only insure that you have to do this again. I had 3 broken on mine.

[jrb92se]

ive been missing that same stud since i bought my car never had any problems yet i know i need to replace it but im lazy

[l0nestar]

Integra7,

What is the stock part number for the studs?

[integra7]

Integra7,

What is the stock part number for the studs?

Exhaust manifold studs (12) - 01151-00471 - JDMExhaust manifold yokes (8) - 14037-42L01 - USDMExhaust manifold yokes (4) - 14037-42L02 - USDMExhaust manifold washers (12) - 14037-01E00 - USDMExhaust manifold nuts (12) - 97812-8401A - USDM

Yokes are the big washers. There are 2 different sizes. Cylinders 1, 2, 5, and 6 used the 8 bigger yokes. While the 3rd and 4th cylinders use the 4 smaller yokes. Those are the prices I paid.
Modified by integra7 at 6:16 PM 12/17/2006

[mello88]

Thanks for the PN's. Cyl #6 studs always seem to break on these motors.

Would anyone else be interested in a "reasonably priced" stainless stud kit? A guy wants to make them for us, but he needs a ~10-15 person GB to offset initial production. It would be a nice alternative to those doing maintenance replacement, manifold upgrade, etc prior to swap.

[l0nestar]

Mello, What is 'reasonably priced'??

Integra7, Here is what I was looking at from McMaster-Carr (McMaster.com)

BEGIN QUOTE:12 x 93210A030 - $2.28 Each $27.36Metric Black-Oxide Finish Steel Setup Stud Round Shank, M8 Size, 50mm Length, 1.25mm Pitch 1x 93795A230 - $4.48 Pack $4.48Class 8 Zinc-Plated Steel Conical-Top Locknut Hex, M8 Screw Sz, 1.25mm Pitch, 13mm Width, 8mm H, Packs of 50 1x 93475A280 - $9.62 Pack $9.62Metric DIN 125 18-8 Ss Flat Washer M10 Screw, 10.5mm Id, 20mm Od, 1.8-2.2mm Thickness, Packs of 100

Merchandise Total $41.46

END QUOTEI forgot about the yokes being different. I could probably drop the pack of washers for $9.62, but meh.. What are the dimensions of the stock studs? The McMaster-Carr site is awesome to look parts up on as well! BTW, where did you get your JDM studs from and how long did it take? (If these studs are good, They can ship today ) Thanks for the help as well!

[mello88]

IDK what pricing would be, somewhere between oem nissan ($50/set) and what phase2 is charging (~$200/set)... But with stainless studs to help eliminate them snapping down the road. Just seeing if there is much interest in this option since there seems to be a problem with the OEM studs, but no "upgrade".

The parts you have listed won't work, you have m8 listed but our studs are m10's. Ok on to the stud dimensions..

The stock studs are 10mm diameter x 50mm overall length x 1.25 pitch. They are double ended:~15mm threads on one end (head)~15mm non threaded section (mani flange+gasket)~20mm threaded section (yolk, washer, nut).

If you add the thicknesses: + Gasket (1mm) + Manifold flange (15mm) + yolk (6mm) + washer (2mm) = 24mm + Threaded into head (15mm) = 39mm + 5-10mm of threading for the nut = 45-50mm overall length needed

The yolks are different OD's because the 1,2 and 5,6 manifold holes are slotted to allow for some expansion. So the Yolks have to cover different areas.

The stock washers have a concave face to allow expansion under heat while the nut is torqued. I don't know if going with a flat washer instead will have bad consequences, there is a reason nissan chose concave washers instead of flat ones.

GL, broken exhaust studs suck!!

[l0nestar]

I realized that they were different when you pointed it out. Where would I order the JDM Nissan studs from? Could I use a piece of M10x1.25 all-thread instead? I know it would be kinda ghetto, but it should work, and I can get it out of stainless.

[integra7]

I would suggest you buy the USDM parts that I listed above. Afterwards, you would only need to find exhaust manifold studs. McMaster studs will work. I found some at Ace Hardware which worked as well. (both places had 50mm)

The stock length is 52mm. 52mm is just enough to thread the nut on there. Once you torque it down properly, I believe there is only 1mm sticking out beyond the nut.

Oh, I got most of my JDM stuff from Nismoparts.com.

[l0nestar]

What about replacing the 52mm studs with some 60mm all-thread? (I love a challenge : ) I don't have to have the studs this week, but I would like them in them soon. I'll have to search around I guess. I wish McMaster sold the studs in M10 instead of M8 . Again, thanks for the info!

[integra7]

depending on your manifold, using longer studs may cause installation issues

[l0nestar]

Stock ATM, but highly considering the JGY manifold. Hit me up on AIM if you want. I'm on now.

[mello88]

Bump for some more info for those looking for OEM RB exhaust manifold studs, washers, yokes, nuts:

(12) Exhaust manifold studs - 01151-00471 Courtesy told me this wasn't a valid US part number... But according to Shay @ NismoParts.com, it is valid -- but it's an Infinity part number! Ordered from Shay @ Nismoparts.com

(8) Exhaust manifold yokes - 14037-42L01 - Readily available Courtesy/Nismoparts.com

(4) Exhaust manifold yokes - 14037-42L02 - Readily available Courtesy/Nismoparts.com

(12) Exhaust manifold washers - 14037-01E00 - Readily available Courtesy/Nismoparts.com

(12) Exhaust manifold nuts - 08912-8401A - According to Courtesy "97812-8401A" is is not a valid PN. I looked the nuts up in FAST and found a new PN, "8912-84010". Shay @ Nismoparts.com informed me that "08912-8401A" is the superseded PN. Readily available Courtesy/Nismoparts.com

Hope this helps others searching for these parts!

[Shocker]

what where the prices on the studs?

[l0nestar]

Shocker,I ordered the studs and nuts from nismoparts.com (Tacoma Nissan \ Subaru). The studs were $1.55 apiece, nuts were $0.70.

[mattleegee]

damn dude, tacoma nissan/subaru? that is done the road from me!

I found my #6 today broken and #1 loose, possibly broken

Eric sells a custom ARP set for $120 plus shipping maybe i will go with these? For me i wouldnt mind spending a little extra cash for something i dont like to play with (stock intake manifold so i have to destroy my car to take off the exhaust manifold)

Is it pretty easy to get the exhaust manifold off with the motor in? im hopeing i have room to extract that #6 outI never touched the exhaust manifold when i bought the motor and installed so no idea what i gotta do, maybe clean my turbo lines out now

[noodl35]

no need for that

http://www.nismoparts.com/catalog/?section=822

look for exhaust stud on the bottom. Cheap.

btw, damn this is an old thread.

[mattleegee]

haha yeah i know its old but had so much good info in it

[DrifterProdigy85]

I got a set from here

http://www.tweakit.net/shop/pr...4k130

[s14 2510's]

I always use my welder to remove broken exhaust studs. Find a nut that fits over or above the threads You want to see just the stud through the hole in the center. The thicker the nut the better. Turn your wire speed down and the heat up. Give it a tac at first make shure its in the center. then just weld the center of the nut solid trying to weld the stud as much as posible. It will heat up the studd more than the block and most times come right out. Might take a few times to get a good weld on it but this works better than ez outs for me.