[geeyoutoo]

High pitch squeal on a ZD30 that goes away after engine warms up is 99.999% of the time, a warped exhaust manifold.

Sure is and not that uncommon.

 

[geeyoutoo]

I'm not sure I'll take a look. From what I've read the advantage of keeping the old one is it has been heat cycled and is less prone to warping in the future

Yes that is how I view it as well, the manifold has 'normalised'. The funny thing is this is relatively common on a CRD but uncommon on a DI, this could mean there may have been a change in supplier at some time who has a slightly different casting and curing process, or the original manufacturer changed their process.

 

[geeyoutoo]

I thought it was the result of the CRD running at higher EGT's rather than an actual change in the manifold

I doubt it, the early DI's would run at very high EGT at times, long story as to why and written up elswhere, this was part and parcel of the grenade issue, I know that after mine was rebuilt using later pistons, about 30,000k later I fitted a boost and EGT gauge and was shocked at what I saw under certain conditions, under 5psi boost and 700c+, so some immediate actions were taken.
I think something else chenged to make them warp.

 

[geeyoutoo]

My exhaust manifold has warped, looking for some advice:

• Is there anyone that manufactures one that isn't prone to warping?
• If not, am I going to get better longevity out of a new one or machining my current one?
• Does anyone know somewhere in the south eastern suburbs of Melbourne that does a good job machining them?
• Patrolpart sells a brand new exhaust manifold and a gasket and stud kit, it also sells ones they have already machined and then you send your warped on back in for 150$ deposit return. I'd assume the brand new one is the way to go, but does anyone know a reliable seller with a better deal?
• The mechanic that looked at it said there might also be issues with the turbo, but he wouldn't know until he pulled it apart and had a look at it. Can anyone suggest a good turbo if I do end up needing to replace it?

Any help would be much appreciated, thenks.

Mate you already have a thread on the same subject, this causes confusion for people who reply and also for later searches, I'll merge this with your original thread to keep relevant info in one place, there have already been answers in the earlier thread. Have added manifold to the merged title.