Jump to content
SAU Community

Turbo Coming Loose

The Mafia

By The Mafia,
in Engines & Forced Induction

 Share

Recommended Posts

The Mafia Grand Master

The Mafia

Posted
Posted (edited)

Hey everyone, I have a simple question.

My Turbo to Manifold bolts keep coming loose. The Tabs that are there have finally broken from me bending them away to tighten the bolts etc.

Can anyone suggest something that I can use to keep them tight? Some kind of thread locker, or should I be looking at something else? Lock nuts are useless in this situation because the nylon will melt due to the heat.

Surely there is something out there that is heat resistant for this purpose?

I've also thought of other reasons:

1. Exhaust it putting too much weight and play on the turbo, working it loose

2. There is 2 x 10mm spacer plates and gaskets, could be causing a problem or helping it work loose?

3. Something wrong with the manifold bolts \ studs?

4. Maybe my atmospheric BOV is causing the turbo to fall off because its too fully sic uleh?

Hmmm.

Any creative input would be good.

Thanks

Jono

Edited by The Mafia
Link to comment
https://www.sau.com.au/forums/topic/207922-turbo-coming-loose/
Share on other sites
The Mafia Grand Master

The Mafia

Posted
  • Author
Posted
You will need to use Inconel studs or they will keep stretching forever.....

cheers

thanks heaps, I didn't realise this.

Maybe I need to change the bolts too because I am not sure what we put in, and if they are stretching they might break...

**RB2530** Proficient

**RB2530**

Posted
Posted

Yes get some good studs and nuts..Dont use bolts as you put more stress in the threads in the manifold when tightening them...Studs and nuts are high tensile so more resistant to tearing so you can get more tightening torque into them..

As far as thread locker on these I never use it....I use heaps of copper based anti seize...Never had one seize but never had one loosen...It lubricates the nuts so you cab get them tighter without damaging threads

Oh and never never never use brass nuts!! (I have been told to use them by Repco believe it or not). You may as well use plastic!!

**RB2530** Proficient

**RB2530**

Posted
Posted

Also make sure you tighten the nuts in a sequence. ie pull the flanges together with a light tension and then tighten each nut in about 2-3 stages...I go diagonally across the flange. Not sure what the Nissan workshop manual says about this but it would be similar...

GeeTR Grand Master

GeeTR

Posted
Posted (edited)
4. Maybe my atmospheric BOV is causing the turbo to fall off because its too fully sic uleh?

LoL, some wee came out :D

Get some stainless sheet, and make some new lock tabs - easy.

Your right i reckon, its prolly the spacer and wot not, increasing thermal expansion abnormally.

In cahoots with marshmallows, s.steel sheet is the jazzle frazzle.

Edited by GeeTR
discopotato03 Grand Master

discopotato03

Posted
Posted (edited)

Mafia often what happens is people fit larger heavier turbochargers and remove the factory turbo's bracing .

I don't honestly have a clue where Nissan supported the std turbo on an RB25 but on FJ20's at least there was some interface I think between the bottom of their std cast dump and I think the gearboxes bell housing .

It needs to provide support in the vertical plane but allow backwards and forwards movement if the dump off the turbine housing is tubular - for lengthwise expansion and contraction .

A while back Sydneykid posted about the lengths GMS had to go to to support the race GTR's twin turbos .

Corky Bell also mentions that turbo exhaust manifolds lead a hard life and one thing they have to be good at is supporting the considerable weight of a turbocharger when they are red hot . Most manufacturers fit a brace and they don't fit anything they don't absolutely have to .

Also while I'm here I have heard stories about exhaust manifolds cracking on RB25's , it only seems to happen if the exhaust is not properly "hung" under the car and or it is too rigid . A big bore exhaust can put lots of leverage into a turbo and manifold , it can also ring like a bell and feed lots of resonant vibration into the cabin area and your brain .

Imo using the factory exhaust hangers or equivalent and maybe some sort of "soft joint" takes considerable leverage and drone potential out of drain pipe exhausts .

Cheers A .

Edited by discopotato03
The Mafia Grand Master

The Mafia

Posted
  • Author
Posted
Make sure you atmo BOV is not facing the nuts...Maybe it is blowing them loose... :D

This reply, simply cracked me up, 110%. Thanks for humoring me today..haha. f**k, we need more fully sic uleh liek this.

thanks for the great replies. I've got some thinking to do, and from what disco has said (thanks too) I will see if I can get a bracket made up to support the flange on my next manifold. Its probably going to be an extrusion honed job. And thats even more of a reason to brace it, as if it cracks I'm going to lose an expensive manifold.

maybe just a angle bar from the bottom of the head flange, welded to the turbo flange, either one or two. That way it will support the weight of the turbo.

As for the nuts commin loose, I've spoken to Dale_FZ1 and he said that the exhaust shops sell these special nuts that are meant for this kind of thing. So I'll grab some of them and whack them on. If they'd have to be the right material to withstand the heat if purpose built for exhausts.

Might be time to bolt on a extrusion honed manifold, and some new gaskets. I might even put the 0.82 rear on and aim for more power? Or maybe not, I'm happy with a V8 style 300rwkw.. haha.

700nm of torque at 3,000rpm feels great.

Tangles Grand Master

Tangles

Posted
Posted

pretty sure a FPR would work great !

Is there enough room on the studs for 2x thinner nuts? the outer nut can help hold it all in tight

The exhaust shop nuts is probably the go.

Or you could try hi-temp industrial sealant/glue to help hold the nuts onto the bolt.

giant Mentor

giant

Posted
Posted

you must use , oem studs and nuts or Inconel (or other high tenstile studs) or you will have this problem for ever!

they will stretch everytime when the turbo gets hots and eventually break off and then you can have a drama removing them.

dangerman4 Mentor

dangerman4

Posted
Posted

hey Jono

i used 4 stainless steel chem anchors with stainless nuts on my gt3582 with some never seize and no locking tabs.

and i run up towards 2 bar and they havent come loose at all so this might be a easy solution for you.

people saying use oem stuff. its impossible there too short

and the nut idea from dale in fine for the nuts but as said previously i think its your studs stretching not the nuts undoing.

the chem anchors i used were 12 x 100 style which is actually a 10mm threaded stud to suit a 12 mm hole + glue

they have a nice little 6mm hex on the end so you can screw them in and out with ease, all you need to do is cut them to suit your length.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • RP1421
      S15 Spec R

      By RP1421 · Posted

      As discussed in the previous post, the bushes in the 110 needed replacing. I took this opportunity to replace the castor bushes, the front lower control arm, lower the car and get the alignment dialled in with new tyres. I took it down to Alignment Motorsports on the GC to get this work done and also get more out of the Shockworks as I felt like I wasn't getting the full use out of them.  To cut a very long story short, it ended up being the case the passenger side castor arm wouldn't accept the brand new bush as the sleeve had worn badly enough to the point you could push the new bush in by hand and completely through. Trying a pair of TRD bushes didn't fix the issue either (I had originally gone with Hardrace bushes). We needed to urgently source another castor arm, and thankfully this was sourced and the guys at the shop worked on my car until 7pm on a Saturday to get everything done. The car rides a lot nicer now with the suspension dialled in properly. Lowered the car a little as well to suit the lower profile front tyres, and just bring the car down generally. Eternally thankful for the guys down at the shop to get the car sorted, we both pulled big favours from our contacts to get it done on the Saturday.  Also plugged in the new Stedi foglights into the S15, and even from a quick test in the garage I'm keen to see how they look out on the road. I had some concerns about the length of the LED body and whether it'd fit in the foglight housing but it's fine.  I've got a small window coming up next month where I'll likely get a little paint work done on the 110 to remove the rear wing, add a boot wing and roof wing, get the side skirt fixed up and colour match the little panel on the tail lights so that I can install some badges that I've kept in storage. I'm also tempted to put in a new pair of headlights on the 110.  Until then, here's some more pictures from Easter this year. 
    • joshuaho96
      R32 GTS (RB20DE) Injectors Replacement

      By joshuaho96 · Posted

      I would put a fuel pressure gauge between the filter and the fuel rail, see if it's maintaining good fuel pressure at idle going up to the point when it stalls. Do you see any strange behavior in commanded fuel leading up to the point when it stalls? You might have to start going through the service manual and doing a long list of sensor tests if it's not the fuel system for whatever reason.
    • perry_r33
      R34 GTR Vspec Garage Sale - All must go!

      By perry_r33 · Posted

      Pm sent 
    • Robot
      Skyline v36 350GT sedan hunting on idle

      By Robot · Posted

      Hi,  Just joined the forum so I could share my "fix" of this problem. Might be of use to someone. Had the same hunting at idle issue on my V36 with VQ35HR engine after swapping the engine because the original one got overheated.  While changing the engine I made the mistake of cleaning the throttle bodies and tried all the tricks i could find to do a throttle relearn with no luck. Gave in and took it to a shop and they couldn't sort it. Then took it to my local Nissan dealership and they couldn't get it to idle properly. They said I'd need to replace the throttle bodies and the ecu probably costing more than the car is worth. So I had the idea of replacing the carbon I cleaned out with a thin layer of super glue and it's back to normal idle now. Bit rough but saved the car from the wreckers 🤣
    • GabsReDeal
      R32 GTS (RB20DE) Injectors Replacement

      By GabsReDeal · Posted

      After my last update, I went ahead with cleaning and restoring the entire fuel system. This included removing the tank and cleaning it with the Beyond Balistics solution, power washing it multiple times, drying it thoroughly, rinsing with IPA, drying again with heat gun and compressed air. Also, cleaning out the lines, fuel rail, and replacing the fuel pump with an OEM-style one. During the cleaning process, I replaced several hoses - including the breather hose on the fuel tank, which turned out to be the cause of the earlier fuel leak. This is what the old fuel filter looked like: Fuel tank before cleaning: Dirty Fuel Tank.mp4   Fuel tank after cleaning (some staining remains): Clean Fuel Tank.mp4 Both the OEM 270cc and new DeatschWerks 550cc injectors were cleaned professionally by a shop. Before reassembling everything, I tested the fuel flow by running the pump output into a container at the fuel filter location - flow looked good. I then fitted the new fuel filter and reassembled the rest of the system. Fuel Flow Test.mp4 Test 1 - 550cc injectors Ran the new fuel pump with its supplied diagonal strainer (different from OEM’s flat strainer) and my 550cc injectors using the same resized-injector map I had successfully used before. At first, it idled roughly and stalled when I applied throttle. Checked the spark plugs and found that they were fouled with carbon (likely from the earlier overly rich running when the injectors were clogged). After cleaning the plugs, the car started fine. However, it would only idle for 30–60 seconds before stalling, and while driving it would feel like a “fuel cut” after a few seconds - though it wouldn’t fully stall. Test 2 – Strainer swap Suspecting the diagonal strainer might not be reaching the tank bottom, I swapped it for the original flat strainer and filled the tank with ~45L of fuel. The issue persisted exactly the same. Test 3 – OEM injectors To eliminate tuning variables, I reinstalled the OEM 270cc injectors and reverted to the original map. Cleaned the spark plugs again just in-case. The stalling and “fuel cut” still remained.   At this stage, I suspect an intermittent power or connection fault at the fuel pump hanger, caused during the cleaning process. This has led me to look into getting Frenchy’s fuel hanger and replacing the unit entirely. TL;DR: Cleaned and restored the fuel system (tank, lines, rail, pump). Tested 550cc injectors with the same resized-injector map as before, but the car stalls at idle and experiences what feels like “fuel cut” after a few seconds of driving. Swapped back to OEM injectors with original map to rule out tuning, but the issue persists. Now suspecting an intermittent power or connection fault at the fuel pump hanger, possibly cause by the cleaning process.  
×
×
  • Create New...