A Little Exhaust Assistance Required

[Skibum346]

My 1990 Disco V8 has a rather throatier than normal sound due to a blowing exhaust. I've mananged to identify the source now, the drivers side manifold has lost at least one stud, possible two.

Does anyone have any experience of removing broken studs and replacing them?

I have booked a date with Douglass Motors but their first slot is 16th of May and I don't relish the idea of cntinueing with my Harley Davidson impression till then.

The really important bit that concerns me is this is my daily drive and I can't affoerd for it to be off the road for more than a fortnight. Any advice or assistance would be warmly welcomed (probably with bacon butties and a beer at the next pub meet!).

Skibum

[Les Henson]

Are you sure the stud is broken? It's more common for the stud to come loose and unscrew itself. If there isn't enough stud left sticking out of the head to remove with mole grips or similar, then the head may well have to come off for the stud to be drilled out. Poke a match or something in the hole and see how far it goes in.


Les.

[petergalileo]

My neighbour had exactly the same problem, he took the manifold off, and welded a stud to the manifold with a mig welder.  He did it 2 or 3 years ago and he has had no trouble with it since.

If its snapped inside thats the easiest fix, studs are notoriously difficult to remove on a manifold and if its snapped below or level with the manifold you could try drilling it out and retapping maybe a thread size higher and you would need to drill the receiving hole bigger too.  

You could also have a look on eblag for a replacement manifold, I picked one up a couple of years ago for £3.99 !

Peter

[Range Rover Blues]

Is it the stud intot he ehaust manifoild that's gone ie the downpiep gasket?

If so then they can be drilled and re-tapped or you can swap the whole manifold.

Get a set of manifold to head gaskets and take the manifold completely off.

[Skibum346]

Sorry guys... wasn't too clear.. it's one of the studs holding the exhasut manifold to the y-piece of the exhaust (down pipe?).

Thanks for the advice and ideas... got a mechanic friend popping over Saturday... I hope! We'll see what happens.

Skibum

[freelanderpx54]

you could drill it out and use helicoils

[Tyke]

Mig the whole lot together . . . . problem solved . . . . for a while . . .  


http://www.coastlinecharitydrive.co.uk/

[Range Rover Blues]

Can you MIG to a casting?

[Tyke]

I would have though so, might not be the strongest weld but it should take.


Could always braze it if not  


Solution really is a new manifold but it's down to how much trouble it takes to get the old one out.

[jaws]

i had this trouble last monday.had to drill the *ucker out. was solid an took time to drill, start with a small drill bit like 1/8th then gradually work up to i think it was a 9mm i ended up using. then tap it out, may be wrong with the 9mm but you will know by the size of the stud you replace it with.

be warned the studs are really hard, like drilling out high tensile, i did try weld a nut and washer to the stud but couldn't move it.

hope this helps  

[Range Rover Blues]

Yes we used to order COBALT drill bits for sheared studs.

IRC the thread is M8 so a 7mm drill bit should do the job.

[Tyke]

IRC the thread is M8 so a 7mm drill bit should do the job

6.9 to be precise . . . . for a 'new' thread . . . . I'd go for a 6.5 max . . . . unless your confident the drill wont 'drift' . . . . then run a tap through it  . . . . before the welder comes out as as the last resort . . . .

[jaws]

sure mine was m10 bolts but it doesn't matter anyway the job got done an doesn't blow!

tyke u goin for the drive on the 28th cause some havoc on the humber bridge? think a few of us are meetin up sat nite!