Cylinder Head Stud Replacement

I am sending my head off to have inserts installed where the exhaust nuts stripped the threads. While removing the head, one of the studs that are in the cylinder base (9+10 in the torque diagram) came out with the nut. As you can see from the picture the washers were totally misshapen. Each left a bit of fused washer on the stud. I am replacing both studs and washers, of course. My question is what is the proper procedure to install the new ones? Is there a torque value that needs to be set on the studs themselves? The nuts and washers are not white, just overexposed.

Studs are never torqued in place. Only screwed in to the correct depth. Locktite used to hold it in place is good.

If the stud is bottomed in the hole then any torque applied to it will be subtracted from the torque the stud and nut is capable of holding.

So true. Bottoming out is the danger. Those washers are a joke . Previous owner ? Genuine n' good to go.

Thanks. Those were the washers that were there last time I took the head off. I put them back in. They certainly did not look like that. I ordered a new set of studs and washers. Locktite it is.

Allways read the directions . Three drops , Id say.

Are those washers aluminium? They should be steel.

pommie john said:

Are those washers aluminium? They should be steel.

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Its hard sometimes to tell an aluminum (aluminium) washer from a freshly plated steel one. If in doubt, check with a magnet. Washers for those studs , part #000011, should be 5/16" x 5/8" flat washers.

BillT said:

pommie john said:

Are those washers aluminium? They should be steel.

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Its hard sometimes to tell an aluminum (aluminium) washer from a freshly plated steel one. If in doubt, check with a magnet. Washers for those studs , part #000011, should be 5/16" x 5/8" flat washers.

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I can check later. I am sure they are steel but they are pretty mangled. I remember when I took the head off months ago and two washers fell out. I posted a picture here because I was not sure where they came from. This is the pic and I am pretty sure they are the same washers.

I made the mistake of using spare washers instead of the correct ones purchased later from Walridge. The correct ones are thick steel (almost 1/16") and should hopefully not deform. I also put the same washers on the inverted studs resting against the cast iron cylinder fin even though they are not called of in the parts book. I'll report back later. 2nd road test will be on Sunday.

Grade 8 washers are what you want

Mark F said:

Grade 8 washers are what you want

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I agree with this but would take it a bit further. They are almost thin spacer that will not give rather than thick washer.
I am worried about the shape and integrity is the surfaces the except the spacer/washers. By the looks of what you removed, some resurfacing may be in order.

I am sure your studs are fine along with the nuts. They will reset just fine.

Now I am confused. Those washers are aluminum and I am sure the ones that came out of there originally were steel. I am usually very anal about replacing parts exactly where they came from. I could not find them in the box of replaced/discarded stuff.

New washers along with studs have been ordered from Old Britts.
The seating points on the head where those washers go appear to have no damage.

Be careful when you get the 000011 washers. They are supposed to be 5/16 x 5/8 x .060. I think you will find you get a couple of standard SAE washers from OB which are more like 5/16 x 11/16 or 3/4 and thinner than .060. That's about the only criticism I have of OB, they send you SAE washers. Maybe I'm just being anal.

Dave
69S

DogT said:

Be careful when you get the 000011 washers. They are supposed to be 5/16 x 5/8 x .060. I think you will find you get a couple of standard SAE washers from OB which are more like 5/16 x 11/16 or 3/4 and thinner than .060. That's about the only criticism I have of OB, they send you SAE washers. Maybe I'm just being anal.

Dave
69S

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I don't think you are being anal. Those washers need to be thick enough to hold torque specs of the head and not flex into the soft alloy.

ARP supplies great washers for that application. They are available in a 2 pack- part number 200-8580. They are .120 thick and hardened. .625 OD Jim

These are not ordinary flat washers. They are machine washers and are much thicker.

The ones on each side of the spark plugs are .080" to .100" thick. The one you are presenting are not that thick but should be heavy duty in nature, enough to take torque without flexing.

most washers you buy off the shelf are a softer steel than that used in automotive. Washers under head bolts are made for the job. They are always better steel and thicker. they will not deform like yours. They are meant to spread the load especially on an alloy head. Never fit a head bolt without the correct washer under it. regards, Dereck

The last time I put my cylinder head back on I had also had all of the fasteners Cad plated, along with a lot of other BSA, Triumph and Vincent fasteners. It took a while to find all the Norton fasteners so I could put my head back on from that box. When I put the head on one of the nuts on the small studs would not torque up properly. I figured something was stripped, but decided to ride it anyway. It leaked a lot of oil.

When I took it apart the following week to fix it, I found that I had also put an aluminum washer under one of the nuts. It was mashed and looked just like the two in your photos. I am not sure where that washer came from. It must have been in my big box of cad plated stuff. Those kind of washers are sometimes used as gaskets on drain bolts etc. The lack of holding from that stud due to the ruined washer also caused the pulling of the 3/8" stud in the head. Once I replaced the washer (and recoiled the stud) it was fine. Then I had another problem. One of the 3/8" head bolts would not torque up to 30 foot pounds. It would only go to 28 and that was it. More turning and the bolt stayed at 28 foot pounds. I am riding it again and have ordered some new bolts. I will have to do the whole job over again before the Ashland Rally. I am getting really fast at it now! I think maybe all these bikes are so old now they should have new bolts and studs really. I think re plating them was not a good idea. I should have just bought new ones.

Nigel