Which Way is Up?

[sloopjohnrb]

Just about to fit 6 new manifold studs to a recon cylinder head, (948 cc).

When I was removing studs from the old cylinder head, I noted everything down EXCEPT, which way the manifold studs fit into the head!

The studs have a short threaded part, a solid non-threaded part, and then a longer threaded part.

Given the bad luck I've hasd recently, I'd like to check which end goes into the cylinder head and which end carries the manifold and the manifold nuts, well before I start.

I'd be really gateful for a heads up.
Best wishes[frame][/frame]

[Alec]

Hello John,

a bit of a guess but I'd say that the shorter threaded end goes into the head. However if you screw a nut onto the long end with a couple of threads proud, slip the thick washer onto the stud then check the stud through the manifold, if the plain section is virtually hidden in the manifold then that's how they go. The reverse if there's a fair bit of plain section showing?

Alec

[Matt Tomkins]

i believe that the shorter ones are a coarser thread. and i belive that this is the side which goes into the head. IF they are indeed diferent threads, check which end the brass nut fits on and screw the other end into the head

[bmcecosse]

Nope - same thread both ends -short end in head.

[sloopjohnrb]

Many thanks indeed.
I am , as always, very grateful for all your help.
Best wishes
John

[Matt Tomkins]

Nope - same thread both ends -short end in head.

-- it's the oil filter suds which are different threads isn't it?

[bmcecosse]

Most studs are coarse thread in the 'block' end - and fine thread for the nut - just not these ones !

[Matt Tomkins]

Most studs are coarse thread in the 'block' end - and fine thread for the nut - just not these ones !

at least i wasn't being completely stupid, then

[bmcecosse]

It's a common mod to replace the two outer studs with 5/16 UNF screws - makes removing/fitting the manifold (and head gasket changes) MUCH easier.