A50 cylinder head torque advice

[Mick Boon]

I need to check the torque settings of my cylinder head, what do I have to do to get access to all the nuts ?

Thanks

[chaz]

quick reply
remove rocker shafts and turn down a socket to suit the inside ones.
long reply
has the head been off recently and does the barrel threads need cleaning out to obtain correct torque?

[AdrianS]

You will probably have difficulty in getting them all torqued a accurately. Some of the nuts are difficult to access, some you cannot get a socket on; I had to turn down a socket to get on the middle bolt so much that I feel the socket will snap at the correct torque. One of my head bolts can only be tightened with an open ended spanner as the corners of the bolt hit the head casting.
Torque up in stages the ones you can access easily, tighten in stages the others as best you can.
As a matter of interest, when I took my head off, 2 bolts were virtually finger tight and there was no consistency in tightness and the head gasket did not blow. Many bike owners of yesteryear didn't possess a torque wrench.

[DAVE BRADY]

Hi,

A 3/8 drive socket will fit the centre bolt and follow the sequence for tightening that is in the manual.
All bolts and nuts can be torqued properly.  The nuts are the trickiest and I would suggest that if the corners of the bolt head or nut is fouling the casting then ease the casting a bit to get a better fit.  A 'crow's foot' can be used to get the nuts right and there are a few threads on the forum about this.  Try a search to find these.  Obviously the rocker box cover has to come off and the exhaust rocker shaft has to be removed.

Dave.

[Bess]

Hi,
     Here's a good thread:

https://www.bsaownersclub.co.uk/bsaoc_forum/index.php?topic=11289.msg59893#msg59893

Best wishes...

[Mike Farmer]

 

I  Cap Heads (allen bolts) 1n the two rear places. Works a treat with the thicker washers. They are also a bit harder so there should be no stretch.

Mike

[Mick Boon]

quick reply
remove rocker shafts and turn down a socket to suit the inside ones.
long reply
has the head been off recently and does the barrel threads need cleaning out to obtain correct torque?

I would like to torque what I can ( with dismantling as little as possible ) as my bike has a small leak on the left hand side when the bike is on the side stand,,, that + the outer nuts have no washers underneath them.  I have new washers but there is no way I can get a socket on the nuts anyway. 

[DAVE BRADY]

Hi Mick,

As an absolute minimum put the washers on the nuts and if you can get a ring spanner on the nuts do them up as tight as you can.  This may or may not work.  One concern is that there may not be any nuts on any of the bolts in the rocker box.

Dave.

[Martin S]

For the nuts which cannot be accessed with a torque wrench I used an open-ended spanner and pulled it with a spring balance. I first "calibrated" this using a ring spanner and the spring balance on one of bolts which can be accessed with a torque wrench. Not the last word in accuracy, but better than guessing.

[DAVE BRADY]

Hi,

In my last post it should have said 'any washers on any of the bolts'.

Dave.

[AdrianS]

For the nuts which cannot be accessed with a torque wrench I used an open-ended spanner and pulled it with a spring balance. I first "calibrated" this using a ring spanner and the spring balance on one of bolts which can be accessed with a torque wrench. Not the last word in accuracy, but better than guessing.

I tried the spring balance method but failed miserably.

[Mick Boon]

Hi,

In my last post it should have said 'any washers on any of the bolts'.

Dave.

There are washers on all the bolts under the rocker box, it's just the four nuts that can be seen from the ourside that have none.

[Mick Boon]

The washers on the four ouside nuts seem to have done the trick. Thanks Dave.