question Exhaust manifold to downpipe studs seized and corroded

[Rover8FFR]

I guess we ave all suffered from this one.

 

Heated the nuts up and shot some lube in there as well.

 

Used my trusty Erwin socket as it looked a bit rounded of, and......Snap!

 

Now got snapped studs in the manifold piece on my Humber Pig!

 

As they are so corroded I have a couple of options.

 

1) Take off and soak after using a cut off tool on the last stud to see if they may still unscrew out.

 

Or

 

2) Take off and get drilled out. Re-tap with new studs.

 

I will need new studs so probably option 2 is the most sensible.

 

I do wish when people did a replacement in the past they didn't use cheap mild steel nuts etc.

 

Nevermind the brakes are more of a challenge if I am honest and a bit more important

 

Curious what experiences others have had with studs!

 

Ta

[fv1609]

Take it off, clamp it cautiously in the vice, drill holes in studs as large as you can without damaging the thread in readiness for extractor tool of the largest size that will engage.

 

Heat up one stud & surrounds to cherry red. Wearing leather gloves dive in quickly with the extractor tool. Don't expect to undo in one go just be grateful to get a bit of small movement each time.

[Rover8FFR]

Take it off, clamp it cautiously in the vice, drill holes in studs as large as you can without damaging the thread in readiness for extractor tool of the largest size that will engage.

 

Heat up one stud & surrounds to cherry red. Wearing leather gloves dive in quickly with the extractor tool. Don't expect to undo in one go just be grateful to get a bit of small movement each time.

 

Thank You. my worry is tat they are so corroded that they may snap twice!

 

Ill give it a go though and see if the blighters shift etc.

[mash]

As stated heat to cherry red, soak in plus gas or similar, heat, soak in brake fluid ....... Repeat this a few times then extract as stated above.

[RichardT10829]

Heat the stud up cherry red and melt paraffin wax on the hot nut.... The wax penetrates into the threads. Allow to cool... Re heat and the nut / stud will extract. Alternate soak it in diesel.

 

 

i have used the paraffin wax method many times 100% success.

[Tony B]

Freezer spray can help, especially on disimilar metals. My favourite penetrating mix is old gear oil and disiel. A decent set of stud extractors is well worth the investment. I have a Halford's Advance set, they make life so much easier.

[Richard Farrant]

If the stud has not broken off flush, get a nut that will slide over and weld it to the stud, this will in turn heat the stud up expanding it in the hole, flood it with easing fluid as it cools, but use a spanner and gently move it backwards and forwards a fraction at a time and you will find it will work free. Better than having to drill and tap.

[Rover8FFR]

If the stud has not broken off flush, get a nut that will slide over and weld it to the stud, this will in turn heat the stud up expanding it in the hole, flood it with easing fluid as it cools, but use a spanner and gently move it backwards and forwards a fraction at a time and you will find it will work free. Better than having to drill and tap.

 

great one Richard. Thanks.

[sirhc]

I have used the same trick Richard suggests before too and it does work.

[tankdriver]

If need be, make your own inserts.

 

Drill it out to the next larger size bolt. Tap it, screw in new bolt, cut it off flush, then drill and tap the new bolt you just screwed in, to the original size.

 

I have made hundreds of them over the years. I used to repair air nailers 8 hours a day, and the were bad on striping out the bolts that held the nose on.

[RichardT10829]

Stud extractors would be a last resort for me... They are hardened and if they snap they are a pig to drill out... It's doable but what a pain !

 

As as for drilling then tapping and inserting bolts etc ? Don't bother..... If that's the road you need to go down then helicoil the thing. I have had to helicoil a number of head stud holes on engine blocks over the years, if done properly they are an excellent fix.

 

Richards method of the nut is preferable route too.... You find that the heat from the welding often cracks the stud free too.

 

good luck !

[Rover8FFR]

_{Thanks for this. More good learnings passed on.}

_{I hadn't thought of Helicoils}

I need to chop my bust downpipe off and then take the header manifold off to do this properly.

I wonder if Clive knows about gaskets and availability?

[fv1609]

_{I wonder if Clive knows about gaskets and availability?}

 

_{Yes these are in stock}

[Rover8FFR]

Yes these are in stock

fantastic news.

set aside in the parts for collection please.

are they available commercially too??

[fv1609]

are they available commercially too??

 

These will do:

 

http://www.ebay.co.uk/itm/2-Copper-Exhaust-Gaskets-Standard-Vanguard-/291305777283?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item43d32d6883

 

Hole centres differ slightly but as they are larger, studs go through fine. You just need to trim the overlap (observing due safety precautions)

 

[Rover8FFR]

Excellent. Thanks.

Acquired for reassembly.

[fv1609]

What you've bought them?

 

You wouldn't have had to pay postage on mine :undecided:

[Rover8FFR]

What you've bought them?

 

You wouldn't have had to pay postage on mine :undecided:

 

Did you say you had some for sale? Missed that and didn't assume Clive.

Dont worry as I would like a few anyway if I can acquire more from your stock etc.

thank you

[fv1609]

Did you say you had some for sale?

 

I took this to be a confirmation:

 

fantastic news.

set aside in the parts for collection please.

 

But anyway you will need several sets in reserve. Not because they fail but other maintenance in the exhaust system may require their replacement.

 

BTW that manifold in the picture will be different from yours

[Rover8FFR]

Silly me !

yes you're right.

More the better and for maintenance etc......

thank you

[fv1609]

Whilst you have that Y piece off go round the edge of the circular mating surface with a round stone & get it really smooth. Also with a flat stone this time get the down pipe surface equally smooth. I smother the mating surfaces with copper grease that allows effective snuggling in & the residue I hope helps burn itself in enhancing the seal. I don't have great confidence it exhaust pastes.

 

 

 

 

 

I have found it best to loosen up the rest of the exhaust system & then tighten the Y piece to down pipe as priority & then tighten up down the system. Otherwise you maybe perpetuate an established misalignment or a replacement component that is very slightly different.

 

You have a hardly used down-pipe in the trailer. I know you have various take-off silencers from Dale. I may soon have a reasonable take-off from my Pig. It has a series of little holes along the base due rust from condensation. I'm not sure whether I will repair those but with the various jobs piling up I may have to fit my only remaining NOS silencer.

[Rover8FFR]

Whilst you have that Y piece off go round the edge of the circular mating surface with a round stone & get it really smooth. Also with a flat stone this time get the down pipe surface equally smooth. I smother the mating surfaces with copper grease that allows effective snuggling in & the residue I hope helps burn itself in enhancing the seal. I don't have great confidence it exhaust pastes.

 

[ATTACH=CONFIG]99219[/ATTACH]

 

[ATTACH=CONFIG]99220[/ATTACH]

 

[ATTACH=CONFIG]99218[/ATTACH]

 

[ATTACH=CONFIG]99221[/ATTACH]

 

I have found it best to loosen up the rest of the exhaust system & then tighten the Y piece to down pipe as priority & then tighten up down the system. Otherwise you maybe perpetuate an established misalignment or a replacement component that is very slightly different.

 

You have a hardly used down-pipe in the trailer. I know you have various take-off silencers from Dale. I may soon have a reasonable take-off from my Pig. It has a series of little holes along the base due rust from condensation. I'm not sure whether I will repair those but with the various jobs piling up I may have to fit my only remaining NOS silencer.

 

Great advice.

Yes I have a NOS silencer and spare downpipe.

if you don't want if replaced the silencer I will take off your hands as an emergency item I can future repair. If that's agreeable? With downpipe in trailer I will have a spare system in the main.

 

Have you ever replaced the pipe to rear before? Was it genuine or alternative??

 

cheers

[fv1609]

Have you ever replaced the pipe to rear before? Was it genuine or alternative??

 

Never found a usable genuine rear pipe. Always had to bodge. There must suitable replacements out there, the trouble is one can no longer rummage looking for likely matches or at least adaptable ones in exhaust fitting shops.

 

They can only cope with the model & year of the car = Brick wall :banghead:

 

Nor can one be escorted around the stock room to look for likely items.

 

When I first replaced the Hornet exhaust I had to use bits from a Citroen car & a Midivan. That actually was more complex but that was in the days I could rummage through stock.

[Rover8FFR]

That's what I suspected. The last 2' of mine has gone :cry:

 

Right hit at the last hanger bracket, so probably can cut back and fit an extension before bracket with a straight section about 3' long ?

[fv1609]

The last 2' of mine has gone :cry:

Yes mine's been getting shorter over the years, but 2 ft is a lot to lose :red:

 

 

Right hit at the last hanger bracket, so probably can cut back and fit an extension before bracket with a straight section about 3' long ?

I have seen flexible used but it doesn't look very nice.

 

Perhaps get some thick stout wire/cable so that you can simulate the shape & distance of the required pipe. Measure the ID of silencer outlet then with callipers look for pipe that has that OD. Try looking through Rover bits first & maybe when you get any visitors ask to look at their tail pipes & see if there are any that might be cut down. So you can go to an exhaust place armed with a make, model & year.

 

Then tell us all please.