Yamaha XJ 900f Cylinder Head Removal

So l have to remove the head and the four nuts at the intake side and ten dome nuts l can move. The two on the exhaust side were sheared off when l bought the bike. Has anyone else had this problem and are these two nuts critical to sealing the head gasket (which l assume they are at the front on the cam tunnel?

 

You really are a responsive bunch.

 

Yes, they are important for sealing!

 

Can you get purchase on the studs to unscrew and replace them?

 

I believe xjforever might sell them. Best thing to do is to take the head off, and use some heat and vise grips to remove the studs. Then use the double nut method to put the new ones in.

 

Thanks guys for your answers
It has been easy so far dismantling the engine this is the main opportunity l have to improve my skills.

 

Unfortunately they are not on the engine. Sheared off.

 

I cannot get the old ones out going to have to put the blowtorch on it l think.

 

Yeah I had a head stud that gave me trouble coming out. Ended up having to use acetyline torches, a stud extractor, and a 1/2 impact. In the end it took half the threads with it so I might be doing a helicoil.

 

I am going to do the same l think but it's worth it my XJ ain't dead yet lol.