In the process of stripping my car and having taken the manifold off my Blacktop Zetec (2.0), it looks like the builder has replaced some of the studs.

Two reasons why I say this: Only two or three have the little chamfered, torx type ends I'd expect to see and the others are just threaded bar - which are all rusting quite heavily. Considering this is a new engine and has never been used on the road this suggests these are not great quality.

However, I am concerned that I'm going to try and remove them and find out they've been replaced because the original threads are Kn"£$%*&

Would you try and replace them or just clean the threads up and hope they don't end up too rusty to be functional?

If I replace them, does anyone know the best replacements to use?

[Edited on 25/8/17 by Ron Lang]

There are only two or three studs with male torx drives fitted in most cases. The rest would be bolts. On the exhaust there is one either side with a green spacer that centres the manifold but still allows for expansion ect.

You could use bolts but the engine tends to be in and out a bit on these things and studs may save the threads in the head.

I normally replace the lot with 45mm long grub screws. A dab of thread lock and jobs jobed. Use good quality fasteners or you will be taking the engine out yet again when you shear one of in the head.

Cap head grub screws are normally high tensile 12.9's but not in stainless.

M4 M5 M6 M8 A2 STAINLESS STEEL GRUB SCREWS CUP POINT HEX SOCKET SET SCREW DIN916

[Edited on 25/8/17 by big_wasa]