Manifold Stud & Helicoil Size

[sdemmery]

Hi Guys & Girls

I know this has been done to death, but I need to helicoil Manifold Stud No1. Have had the Squeel for several months nows. Its driving me nuts!

Ive already tried extracting, retapping, but no luck. So Im about to helicoil but am unsure of what helicoil kit to buy. Im refitting a standard stud back, I think the stud is 6mm? is that right? & I need a 8mm hole for the helicoil? So is a "Helicoil thread repair kit M8 x 1.25" what I need? I take it the pitch is the 1.25. Is that the pitch we have on those studs? The M8 does that refer to the internal diameter of the coil? if so should I have an M6. I assumed the 6 or 8 on the M is the size in mm.

I did a forum search, but couldn't find any specifics on helicoil sizes, so if anyone does know It would be a great help.

Cheers

Stu

[Dolly1]

Hi,why complicate the issue.Drill 6.75 n tap 8mm.

[sdemmery]

Thanks for the quick response.

I have already tried to drill out & retap to the original size, but but luck. Are you suggesting using a larger 8mm stud (are the originals 6mm?) If so I guess thats a good option. Ive heard that a helicoiled thread is much tougher than a thread straight into the ally head this was also a considration for helicoiling for me. I dont want to have to do this job again

It also seems that most posters here with this issue tend to helicoil, I'm all up for doing it different though as long as it works

[sdemmery]

Hi Guys
Well its official I really need to fit a Helicoil to fix Stud No1 problem. I did ask this before but had no response. Maybe I need to say it louder

WHAT HELICOIL SIZE DO I NEED?

Ive read here that someone thought it was M8 but that seems a bit big. Stud only looks like 6 to 7mm in diameter to me. As I said surely someone must know, you are all so knowledgeable in all things bongo

Cheers
Stu

[dandywarhol]

The original stud is 8mm

[The Great Pretender]

Not wanting to hijack this thread but it has got me wondering why number one stud snaps, any idears peeps?

[sdemmery]

Thanks Dandy, I have Standard Studs so 8mm it is then. Helicoil Kit on order

I guess that Stud no 1 breaks as this is the furthest point from what is in effect the fulcrum of a lever. The Exhaust I suppose is acting as this lever in a way Well that was my first thought but Im probably wrong

Thanks again Dandy

Stu

[sdemmery]

Just thought I would keep you all updated.
Helicoil Kit arrived & job is now a good Un! no screechy screechy. Wahoooo. Wish I had done this properly 6 months ago. Mind you I'm dab hand at taking the altenator off now It is true those helicoils are far stronger than the original thread.

Also managed to fit new front drop links while I was about, now the rear ones, thats a whole new topic, but needless to say the nuts are stuck firm & I mean firm, ring spanner breakingly firm in fact

Thanks Everyone for you advice. Question is should I keep the helicoil kit or sell it on? Only cost me £30 & I just know if I sell it I will need it again, best keep it in the garage. But if any of you Bristol guys need a lend you know where to come.

Thanks
Stu

[bongomaan]

no1 stud gone on me,but did your auto box misbehave with stud squealing ? perhaps i have another issue ! (not another !) cheers....

[sdemmery]

Hi bongomaan,

I dont want to shout too loudly as wongo bongo is just behind me on the drive & she may hear me. But no I didnt have any auto box problems. I can't really see how the two could be related. Stud No1 going just caused the exhaust manifold not to seat correctly resulting in a squeel of air escaping.

Oil levels are ok in the auto box are they? Worth a check or even a change I guess.

Good Luck with it

Stu

[bongomaan]

hi stu, thanks for the reply,the stud snapped because i replaced back box and middle section,when i tried it out there it was busteded,i replaced the exhaust because the old one was blocked and she broke down ,just before she went the gear box was hunting i was hoping the two were related but it looks like her issue again !!! but in reply atf fluid red halfway up the stick and no smell of toast !!!!