Cracked manifold - help needed!!

[daveh 0]

Right then, I've been doing quite a few jobs on the C of late - hence all the posts - but this is an expensive one!

 

I'm having a new Magnex exhaust (cat-back) fitted tomorrow. Was supposed to be last Thursday, but the delivery went astray :roll: .

 

Whilst looking over the top of the engine, I noticed what looks like a crack in my (original) manifold. Basically a dark line about 2 inches long where the outlet for cylinders 2 and 3 meet.

 

I guess my questions are:

 

1) Am I right to be concerned - bit worried about CO leaking into the cabin!

2) Do I need a new manifold - if so which one and how much.

3) If I replace the manifold (and the exhaust), should I do the CAT as well.

 

I'm also a bit worried about fitting the new exhaust, only to have to break it apart again (if I change the CAT), so might wait and do the whole thing later in the week.

 

Any comments from those who have been down this road already, greatly appreciated!

[dubbprince 0]

ok mate..well firstly...

 

1.) it should only be a small leak...so nothing majorly to worry about...and it will affect your fuel consumption more.

Have you turned the car on and watched for any watery leaks coming out of the crack?

 

2.) if the answer to above was yes...then maybe...you can get it braze welded with brass rods..but its best to just replace it altogether. If the 2ltr 16v has the same manifold as the 1.8 16v then i can help...i have one in perfect condtion.

 

3.) theres nothing wrong with your cat...so no...dont need to change that, unless you really think you want one...but thats just silly money! :wink:

Sanjay.

[16VG60 1]

The manifolds on the 1.8 and two litre 16V engines are interchangeable. The main difference is the presence of a CO sampling pipe on the 2 litre item. This will not present a problem if the cahange is 2.0 ltre to 1.8 litre. In any case this pipe is very often not used, other than by folks like me, and if push comes to shove go for it. The porting on the 2.0 litre manifold is much better so indeed you might see a slight improvement. If you are unable to move on this manifold i am currently looking for some of these 2.0 litre items myself.

[daveh 0]

Just had the Magnex zorst fitted. Seems ok, although having to return to the garage twice to have it refitted due to the banging as I went over bumps was a pain!

 

I still think the tail pipe should be more central in the rear bumper cut-out, but aparently this is the best they can do :cry: .

 

Also have to return again tomorrow as the tracking adjustment they did still hasn't cured the 'steering-wheel pointed slightly left whilst driving straight'.

 

Anyway, the good news is that the manifold (whilst cracked) is not blowing - no need to mess around with that then.

 

Thanks guys :thumb right:

[don 0]

MINE IS THE SAME, HAS A CRACK, MUST BE THE SAME AS WHY THE SUNROOFS DONT SLIDE JUST TILT, ITS ZE GERMAN. :D

[Kevin Bacon 5]

A cracked manifold is not a good thing. Replace it ASAP. Cracks in cast iron tend to creep over time and get worse, as I discovered in an old BMW some years ago.

 

Unfortunately welding cast iron is a lengthy and difficult process to do properly, so I'd seek a replacement from a scrappy.

 

A Golf one will do, should be plenty about.

 

K

[daveh 0]

Unfortunately I'm not looking forward to the bill for labour (or the option of a DIY).

 

The dealer who fitted the zort said that you have to drop the front suspension to get the manifold off (true??).

 

As the bill for labour will be high, I don't mind spending on the part to get a good result - and hopefully not have to do this again for a very long time.

 

Any recommendations for a new manifold??

[h100vw 0]

A cracked manifold is not a good thing. Replace it ASAP. Cracks in cast iron tend to creep over time and get worse, as I discovered in an old BMW some years ago.

 

Unfortunately welding cast iron is a lengthy and difficult process to do properly, so I'd seek a replacement from a scrappy.

 

A Golf one will do, should be plenty about.

 

K

 

I migged up the exhaust manifold on my mates UNO turbo.. It survived over 2 years til he sold the car. He was lucky not to lose the turbo and downpipe onto the road. :lol:

 

I ground a big groove into the crack with my angle grinder. Then I turned the mig upto 11:shock (160A): I ran a bead down each side of the crack to close the gap, then filled it in. It was a work of art, I was well chuffed as was my mate as he was £200 quid up.

 

Not ideal as a manifold would be much easier to come by for the Corrado. I wouldn't hesitate to do another though, if access was good enough that I didn't have to remove it first.

 

Gavin

[h100vw 0]

Unfortunately I'm not looking forward to the bill for labour (or the option of a DIY).

 

The dealer who fitted the zort said that you have to drop the front suspension to get the manifold off (true??).

 

As the bill for labour will be high, I don't mind spending on the part to get a good result - and hopefully not have to do this again for a very long time.

 

Any recommendations for a new manifold??

 

The downpipes need the subframe dropping to get them out. The exhaust manifold should come out the top, with the inlet manifold off and the down pipe disconnected..

If you have 4 branch fitted it'll defo need to be dropped.

 

Gavin

[daveh 0]

Please don't laugh :wink: ......

 

Just so I know what I am dealing with - there are two main components between the engine and the CAT?? - Exhaust manifold and downpipe??

 

If I go to the trouble of buying parts and tools, clearing my garage out to make space to work, and then beg for help form all sources (including this foum!) to change my exhaust manifold myself, should I replace the (original) downpipe as well??

 

I don't like throwing money away (obbviuosly), but it is nice to do things properly - and I hate taking stuff apart twice when once would do!

[daveh 0]

Just noticed this miltech manifold

 

http://www.awesome-gti.co.uk/vw%20corrado/exhausts.html

 

This seems to replace everything - engine to CAT - but I guess is more difficult to fit (as mentioned earlier).

[h100vw 0]

The downpipes should be ok, just unbolt the manifold from it and the head. The downpipe on a 2 litre has no silencer in it so if you disconnect the cat then you can wiggle it more if needed.

 

That picture on Awesomes website is of an 8V manifold and I'll be having words with Jim about that misleading picture tomorrow, when I call in. :mrgreen: The 16V one looks pretty much the same though.

 

At the end of the day, how much money do you want to spend??? I might have a manfold in my garage come to think of it.

 

Gavin