Exhaust renewal

[shrig1969]

Hello,

My bus is a 1987 1.9DG Hi-top .

I am in preparation to attempt to replace my exhaust system.
I have been reading up a lot on the subject, but still have a couple of questions.
I have soaked, as advised, all the bolts/studs where the exhaust meets the manifold, in plus gas. I have given them a tickle with a spanner and all of them have shown signs of movement

Currently have 4 x studs and 4 x bolts.
Cylinder 2 = studs
cylinder 4 = bolts
cylinder 3 = studs
cylinder 1 = bolts

Q1: If I manage to remove the nuts, can I leave the remaining studs in place and refit the new exhaust onto them?
Q2 : With the bolts out, can I replace with studs or should I keep the same format?

All thats left is deciding on a budget exhaust from brickwerks or going all out and investing in a stainless.

When are the VW exhaust sales season???????

[kevtherev]

I would keep the format
Use stainless nuts and bolts instead.

Is this a late exhaust system, single entry/exit silencer?

[shrig1969]

Yes it's the late exhaust system.

Do you agree with leaving the existing studs in if they won't budge?

[Mark Foss]

If it where me I would try to remove studs possibly with the double nut method. Then replace with stainless studs (or stainless threaded bar of same thread cut to length)

[shrig1969]

Believe me, I want to replace the lot. Just don't want to push my luck and end up opening a can of worms.

Depends on how brave I am at the time .

[kevtherev]

Yes it's the late exhaust system.

Do you agree with leaving the existing studs in if they won't budge?

Yes..if it ain't broke, don't fix it

[ghost123uk]

I replaced all mine with studs and brass nuts earlier this year. Heat is is the trick to getting them off, lots of heat !!

Studs = http://www.ebay.co.uk/itm/281040902364" onclick="window.open(this.href);return false;
Nuts = http://www.ebay.co.uk/itm/1-4-5-16-3-8- ... hash=item0" onclick="window.open(this.href);return false;
Washers = http://www.ebay.co.uk/itm/M8-Stainless- ... 4171247a84" onclick="window.open(this.href);return false;
Gaskets = http://www.ebay.co.uk/itm/VW-Beetle-VW- ... 25a9d7b99c" onclick="window.open(this.href);return false;

Those studs have Allen key heads, making screwing them into the head easy, with the exhaust pipes in place, or not. (thanks to itchyfeet (iirc) for the heads up on that)

If you do go ahead, suggest you check the tightness of the nuts a couple of times in the first few days after doing it. I didn't and though I thought I had them at the right tightness, two of my brass nuts fell off onto the road somewhere

[shrig1969]

My theory behind it was to strip down the old exhaust, starting at the tail pipe and ending at the studs/bolts on the manifold.
Fitting would be the reverse, in sections, joining piece by piece.

I presume the studs twist in by hand until they twist no more???

Also a little bird told me never to use stainless studs/bolts into the manifold because it can react with the aluminium cast make up of the engine???? Completely blew my mind with the technical jargon, but thought I might throw that one into the mix as well.

Thanks for your replies and advice to date.....

[ghost123uk]

I presume the studs twist in by hand until they twist no more???

Pretty much, don't over tighten them though because the end of the blind hole is very thin and on the other side of it is water

Also a little bird told me never to use stainless studs/bolts into the manifold because it can react with the aluminium cast make up of the engine????

I read that too (on here), hence my buying those non stainless, high tensile, black coloured studs and brass nuts.

[NicBeeee]

Also a little bird told me never to use stainless studs/bolts into the manifold because it can react with the aluminium cast make up of the engine???? Completely blew my mind with the technical jargon, but thought I might throw that one into the mix as well.

Thanks for your replies and advice to date.....

Galvanic corrosion, no need to worry unless you are planning on making your van seaworthy, you need an electrically conductive liquid to be able to move electrons between the two dissimilar materials such as salty water. This is why it is not suitable for marine applications. Fine for automotive.

[Smcknighty]

Cue picture of the top gear van

[shrig1969]

Galvanic corrosion, no need to worry unless you are planning on making your van seaworthy, you need an electrically conductive liquid to be able to move electrons between the two dissimilar materials such as salty water. This is why it is not suitable for marine applications. Fine for automotive.

And this is why I love this forum

[shrig1969]

Just bit the bullet and ordered a budget kit from VW Heritage.

Today they have a 10% deal on, so why wait

Will let you know the outcome of my first attempt at an exhaust renewal

[jrt]

All the best' plenty of heat and lubrication. Did ours a fortnight ago-2 snapped studs but all sorted now.
David

[shrig1969]

Ok. Bums twitching. Keep hearing about studs breaking.....

Has anyone ever changed an exhaust with no dramas??
When do they normally break,on removal or can it happen when fitting new ones.

Are the studs a standard length? I am guessing I will need them to be 40mm in length, allowing 26mm to be inserted into the manifold, thus leaving 14mm to screw the nut onto.