TB42 / TB45 Parts Interchangeability

[mhgill]

Is that a word? anyway I'd like to know if The following parts from a TB45 will fit a TB42

Head
Inlet Manifold
Dizzy
P/S Pump
Extractors


Anybody got any info that could help? Cheers.

[create]

Head
TB45 head on TB42 block no go. TB42 head on TB45 block is OK but not advised.

Inlet Manifold
No - inlet manifold unique on TB45 and TB42

Dizzy
can be swapped with some modifications

P/S Pump
Yes direct bolt up fitment

Extractors
Yes direct bolt up fitment

If you want more detailed info just ask.

[create]

I have tried a TB45 head on a TB42 block. "mungaGQ" has a TB42 head on a TB45 block.
I now have a complete TB45 engine in my GQ.

[mhgill]

Why will the head go one way but not the other?

[create]

The TB42 engine has an extra set of oil galleries that feed the head through the front of the engine. If you put a TB45 head on, the galleries arent there and you then get oil leaking out the front of the engine between the block and head. No amount of hylomar could stop it.
There is probably a way around it but I couldnt fix it.
The other problem is that the bore size is different so the head gasket doesnt seal properly over the pistons. I used a TB42 head gasket first and it flapped when the engine ran. I then changed to a TB45 stainless head gasket and it wouldnt seal properly. In the end I just gave up and put the whole TB45 engine in.

[mhgill]

Ok thanks for that, how are the manifolds different?

[create]

Inlet manifold has a completely different stud pattern. I think the ports are bigger too on the TB45

[mhgill]

Top bloke, cheers for that.