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Discussion Starter #1
Having removed the top two Bolts and the two underside nuts, I removed the exhaust rocker cover and noticed that the two hexagonal pillar bolts underneath were finger tight - did these loosen as I undid the two top bolts, or are they likely to have been loose before?
 

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Hi Dave,
They could have been loose before unless the rocker cover bolts were very tight. Don't forget that the pillar bolts are the head bolts so they will need to be torqued down in the correct sequence.

I hope this helps

Webby
 

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Hi Dave W :)
when you say the rocker cover do you mean the rocker box?
If so the two bolts that are loose sound like the to head bolts,
which should certainly be tight.
I would suspect they have not been tightened in the first place,
as they are unlikely to loosen as the rocker bolts lock them up.
If they where loose! loose! I would be removing the head to inspect the head gasket.
 

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Discussion Starter #4
Hi, Yes it was the rocker box, and they were both loose, loose - I have had good compression though (150psi plus).

I guess I will have to take off the inlet rocker box as well so I can torque them down in order?
 

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Hi Dave,
You don't need to remove the other rockerbox to torque down the other bolts. Just remove the rockerbox bolts and then in the head pillar bolt you will find an allen key socket.
They are 7/32", I use a deep 1/4" socket with a length of cut down allen key wedged into the socket with some tape to stop it falling out to torque up the bolts.
Alteratively, you can buy a special tool off the shelf.

I hope this helps

Webby
 

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Hi, Yes it was the rocker box, and they were both loose, loose - I have had good compression though (150psi plus).

I guess I will have to take off the inlet rocker box as well so I can torque them down in order?
What Plewsy is saying I think, is that by being loose, the head gasket may well have been compromised already. Triumph twins are not regarded for head gasket integrity. In this case, gases have already invaded the gasket seal, despite the 150psi compression.

Like John, I'd think this is blown head gasket going somewhere to happen. It may be worth checking this now, rather than be running home on 1 & 1/2 cylinders.

No one has a crystal ball on matters like this. You could just nip the head up and never have a problem, but on the other hand............. there is a fella called Murphy!!!

Nothing bad will happen to the engine if it does blow a gasket, other than they will do this at the most inconvenient of times.

:D RR
 

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I dont have my workshop manual handy here, but I think its stressed that the rocker-box fixing bolts must be torqued (5lb ft???) much lower than the head bolts (18lb ft).
If the rocker box fixing bolts are very tight, its likely that the head (pillar) bolts will loosen.
Also, on mine there`s 3 studs/nuts under the rocker box!
 

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The four inner head nuts will continue to be loose until such time you replace the original head nut washers with the larger 82-2184 washer. These are the same ones used on the four outer head bolts.

The original washer does not present a large enough surface area to distribute the clamping force provided by torquing the head nut. By using the earlier head bolt washer you distribute the load over a larger area. The rocker box gaskets are already sized to fit the larger washer. In some cases a small amount of aluminum has to be removed from the inner edge of teh rocker box adjacent to the washer.

The head nut is loosening because the aluminum is not able support the pressure and the head's aluminum is being distorted. When you remove the nut you will see a small indentaion where the washer was. It is also a good idea to place a small 3/8" "O" ring over the head stud before putting the new washer in place. It is common for oil to drain down the stud and cause a leak between the head and head gasket.
HTH
 

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Discussion Starter #11
The four inner head nuts will continue to be loose until such time you replace the original head nut washers with the larger 82-2184 washer. These are the same ones used on the four outer head bolts.

The original washer does not present a large enough surface area to distribute the clamping force provided by torquing the head nut. By using the earlier head bolt washer you distribute the load over a larger area. The rocker box gaskets are already sized to fit the larger washer. In some cases a small amount of aluminum has to be removed from the inner edge of teh rocker box adjacent to the washer.

The head nut is loosening because the aluminum is not able support the pressure and the head's aluminum is being distorted. When you remove the nut you will see a small indentaion where the washer was. It is also a good idea to place a small 3/8" "O" ring over the head stud before putting the new washer in place. It is common for oil to drain down the stud and cause a leak between the head and head gasket.
HTH
Thanks for that, I'll do it when I have the head off in the winter.

Incidentally I struggled to fit a torque wrench and male hex socket between the frame and inlet rocker area, so I had to guess the settings - made sure the cover bolts were not as tight as the head fasteners.
 
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