13 replies to this topic

[vxbandit]

B******S!!! Found out today that the blowing exhaust is actually 2 cracks in the exhaust manifold. Can anybody recommend a temporary fix till i can get a decent one, which one would people recomend and how much??? I have a Milltek full system cat-back exhaust. Chhers all.

[vxr36]

Just out of interest did it sound a bit like a diesel? I ask as Yellow_Or_Black was trying to pin point a problem recently.

[vxbandit]

No i wouldnt say a diesel just a bit more throaty.

[Mr_M]

B******S!!!
Found out today that the blowing exhaust is actually 2 cracks in the exhaust manifold. Can anybody recommend a temporary fix till i can get a decent one, which one would people recomend and how much??? I have a Milltek full system cat-back exhaust. Chhers all.

Turbo or N/A??

AFAIK on either there's no temporary fix possible - it's unlikly to fail catastrophically so just live with it for now and save the pennies. Other than that....

If it's an N/A I haven't a clue - but I'm sure someone else will be along in a minute

If turbo - only real option is either same again (Z20LET - iirc £900ish) or Astra VXR unit (Z20LEH - iirc £500 ish). In both cases you can't get the maifold on it's own - you need the turbo too (hence the cost). The astra VXR unit is a straight bolt on - as well as being cheaper, the manifold is also a much better casting and the turbo itself is more efficient (so either lower temps for same boost or more boost for same temps... ). Not surpisingly most people seem to go for the Z20 LEH unit......

Dbilias do a manifold for the tubby but it's a pile of poo apparently. There are a couple of other more exotic (read expensive) units out there which allow fitment of other (also expensive) turbos but I think they're probably not relevant unless you've already got to the stage of modded internals

HTH

[daggles]

Unlike a good old fashiond Cortina exhaust manifold our manifolds are realy thin so there's not much chance of doing anything with it. Turbos are deady easy to find on ebay if that's what you need. You should easily get a decent Z20LET for under £200 and an LEH for £250.

[techieboy]

Looking at your signature picture, it looks like you've got an NA. Assuming thats the case, there is an NA manifold for sale in the Parts for Sale section and there is/was one on eBay a couple of days ago. Aftermarket options are the TMS 4-1 work of art but it's uber pricey. Then there is the previously mentions Dbilas manifold. Also, at some point there will be a 4-2-1 manifold from 2Bular but no idea when that will surface. We discovered during an engine rebuild 2 weeks ago, that my manifold is cracked. I've just left it as is, for now.

[Coral flash]

B******S!!!
Found out today that the blowing exhaust is actually 2 cracks in the exhaust manifold. Can anybody recommend a temporary fix till i can get a decent one, which one would people recomend and how much??? I have a Milltek full system cat-back exhaust. Chhers all.

Ouch ouch ouch

If you are Turbo, my understanding is they come conjoined,

Can't offer much in the way of advice here (as a relatively newcomer) but having noticed the number of manifold failures on the forum, I ask you and other forum members:

Aware exactly when the manifold went:

If it blew:

1) During normal driving
2) Driven hard from a cold start


The reason I ask:-

Can this be avoided by not pushing the engine from cold?

[vxbandit]

No it is a tubby. Tbh i cant remember when it went i dont drive it hard from cold because i know it will cause some damage.

[Mr_M]

If you are Turbo, my understanding is they come conjoined,

Can't offer much in the way of advice here (as a relatively newcomer) but having noticed the number of manifold failures on the forum, I ask you and other forum members:

Aware exactly when the manifold went:

If it blew:

1) During normal driving
2) Driven hard from a cold start


The reason I ask:-

Can this be avoided by not pushing the engine from cold?

OK - yes, as said above, the manifold and turbo are a combined unit. You cannot buy either on it's own.

Regarding failure, the manifold is a known weakness of the Z20LET engines in all applications (Astra, Vectra etc) - concensus opinion seems to be that the quality of the casting is poor. Heat is usually the cause of the problem - and if they overheat on FWD cars like the astra (where they're much more directly in cooling airflow) then you can bet the problem is going to be worse in our cars....

Usual place to look for failures btw is where the branches join - shine a good torch down the heat shield 'tunnel' at the back of the engine and you should be able to see any problems. If you want a better look it's the work of a couple of minutes to remove the heat shield. This is what you're looking for:



and for what it's worth my personal experience is that for every crack you can see from above - there are two underneatht that you can't see till you get the damn thing off.

Coral flash - Yes - obeying the usual procedures to safeguard the turbo (i.e. let the enigine warm & cool properly before/after hard use) will help to protect the manifold, but other than that there's not a lot you can do. Even then it will probably go at some point..... as is the way with these things some are better than others for no explicable reason - yours may last another 100k miles... or another 10. No way of knowing.

There is some anecdotal evidence that running at a higher level of tune without the chargecooler can help to accelerate failure - if the engine gets too hot the ignition retards to protect the head - at the expense of higher EGT's and hence higher manifold temps.

Unlike a good old fashiond Cortina exhaust manifold our manifolds are realy thin so there's not much chance of doing anything with it. Turbos are deady easy to find on ebay if that's what you need. You should easily get a decent Z20LET for under £200 and an LEH for £250.

The manifolds can be welded - but remember that even if the cracks you can see are repaired it's quite possible that other cracks that haven't become visible yet are developing nicely....

Also, although replacing the turbo is not that hard a job (albeit a bit of a sod) it's not one you want done more often than necessary - there's always a small chance of a stud breaking off in the head, in which case it can be big bill time.....

Yes - you can normally find turbos (both LET and LEH) on ebay - but they're usually either turbos only or turbos with cracked manifolds or turbos with welded manifolds. You pays your money.... (oh and if anyone does want just a turbo, drop me a pm - I've got both an LET and LEH unit in the garage, both low miles and excellent condition - very reasonable prices and I'll throw in (broken) manifolds with both )

[vxbandit]

Thanks M thats a great help, that is the exact place where mine is cracked.
Can anybody help with this, my German isnt that good and for me it looks like its 1 1/2 Euros???

http://cgi.ebay.de/T...1QQcmdZViewItem

Edited by vxbandit, 10 May 2008 - 08:20 AM.

[techieboy]

From my rusty German it looks like it's from a 2002 Zafira but he's unsure whether it's damaged or not. So it's being auctioned as damaged - just in case. Doesn't mention anything about shipping to UK so you'd need to check.

[The Batman]

a bit of a random question but why do you have na lights on a turbo?

[snoopstah]

a bit of a random question but why do you have na lights on a turbo?

No it is a tubby.

That auction's for a turbo manifold though...

[vxbandit]

The previous owner dinked it and put a NA light on it Got it sorted now im gonna buy the one from courtnay in the next couple of weeks which means i will have an Astra VXR Turbo thats only done 8000 miles for sale if anyone would be interested????