Cylinder head bolts in stainless steel no or go

Hello,

i just finished work on my cylinder head and put it on the cylinder….
i put 4 new head bolts [060401s] near the spark plug in stainless steel from RGM.

They realy look nice and also with this thick washer…

but I heard some rumours that this bolts got no high tensile strength….

Do you know something about it and do you have some experience with these bolts?

I don`t want to retorque and retorque and retorque my cylinder head because of some shiny stainless steel bolts…. if the rumours are right …..


Another question: i`d like to use Nord-lock washers for the cylinder-head bolts…..


What do you think? Pro/cons….

Have a nice day

chris

I fitted SS head bolts on my 750 the same as you 20+ years ago. Head gasket still not leaking yet. HTH
Cheers, Martin

Used stainless from D Middleton in the 80's. High compression motor, no problems whatsoever.

Check out the 12 point ones cNw sell. Top quality, great looks and make torquing the head SO much easier!

peter12 said:

Used stainless from D Middleton in the 80's. High compression motor, no problems whatsoever.

Click to expand...

The ones from Middleton are good quality, I have had them in my 750 Short Stroke race motor until now, fine. But I am replacing them with ARP from CNW.

Nord Lock washers are good where vibration is a problem, I use some on my Yamaha single, but not on the engine. The need to retorque head bolts is not due to vibration, but stretch and gasket compression. So I suspect they would make no difference in this application.

Nord lock washers do their job very well - the job of making it difficult for the fasteners to come loose.
They will do the same for you too when you come to take the head off. You must apply quite a lot of extra torque to push the fastener over the locking ramps. It could be enough to strip threads... or even break stuff.

I have only seen them used on vibey 2t stuff, the owners swore - a lot - that they wouldn't use them again.

As you can see from above posts SS can be successful , the ones fitted by the previous owner to my 850 were not I do not know the origin of them but the heads of the bolts and the washer fretted against each other , they looked to be too soft, fitted standard parts from Andover Norton and had no problem since.

Fast Eddie said:

Check out the 12 point ones cNw sell. Top quality, great looks and make torquing the head SO much easier!

Click to expand...

I also believe this is the way to go.

CNW bolts are the way to go. Made by ARP so strength is not in question. Now they are necked down so that they stretch a bit as the engine gets hot and then come back to the same length when everything cools back down. No more head gasket leaks even with a copper head gasket!! I originally bought the straight ones and when Comstock and CNW came up with the necked down idea Matt at CNW traded me straight across for the new bolts.

Would the CNW / ARP head mounting hardware make even more sense to use on a Combat engine rebuild?

Never had problems with the stainless choice of visual bolts. Ever. Ride on.

Like Fast Eddie and cjandme have said, the CNW bolts are just really nice. The 12 point heads are 3/8-12 point and 7/16-12 point making it easy to get a wrench on them. I built two little 2 inch torque extensions which I use for torquing the head. It is easy to use them at 90 degrees to the torque wrench so your torque readings stay the same.

My engine is a combat with a copper head gasket. The compression is about what it was as a combat but the cam is milder. No leaks after the first thousand miles. (some say that copper head gasket engines always seem to seep up by the exhaust and push rod tubes.) There is a Jim Comstock thread on here about the fact that the Norton aluminum head expands a lot when heated and since the head bolts hold it in place with out stretching enough the head itself distorts and becomes a different thickness so that when it cools the bolts are no longer tight. Jim's idea of necking down the head bolts to allow for some more stretch when the head is hot solves this problem perfectly. The new CNW / ARP head bolts incorporate this idea and work great.

Don't forget to get the CNW cylinder mounting bolts and nuts as well. With the 12 point nuts which are not as tall as the stock nuts you can set the cylinders all the way down before you put the nuts on. To me, these are must have mods.
Dan.

I use RGM stainless head bolts on my bikes and have had no issues in the 7 years I've been using them.
As with all stainless stuff, some lube on the threads to prevent galling is the only precaution.
The CNW/ARP bolts really do look the business though.
http://coloradonortonworks.com/wp-content/uploads/2013/06/IMG_9270.jpg

Trying hard to resist...

Thank you all for the replies!

had my first 100km and no issues....

chris

I have a question about installing the CNW / ARP head mounting hardware. The three 3/8 studs require modifying the head with 3/8-16 heli-coils. I've done lots of heli coils by drilling for them with a hand held drill and never had a problem. The head looks to me like a difficult item to strap down to a drill press to "properly" tap drill those holes. Should I even be considering drilling those three holes with a hand drill for the heli-coils?

pantah_good said:

I have a question about installing the CNW / ARP head mounting hardware. The three 3/8 studs require modifying the head with 3/8-16 heli-coils. I've done lots of heli coils by drilling for them with a hand held drill and never had a problem. The head looks to me like a difficult item to strap down to a drill press to "properly" tap drill those holes. Should I even be considering drilling those three holes with a hand drill for the heli-coils?

Click to expand...

You can drill the holes with a drill but you need a guide plate to do it. I used to use a 2 inch thick iron plate with a hole drilled through it. Just make sure the hole is straight by boring it in a mill [or precision drill press]

Then I had a second hole that was tapped with the helicoil tap in a mill so it was straight. I used that to guide the tap straight into the head.

Don't even think about doing it by eye. Jim

I love it. Thank you.

comnoz said:

pantah_good said:

I have a question about installing the CNW / ARP head mounting hardware. The three 3/8 studs require modifying the head with 3/8-16 heli-coils. I've done lots of heli coils by drilling for them with a hand held drill and never had a problem. The head looks to me like a difficult item to strap down to a drill press to "properly" tap drill those holes. Should I even be considering drilling those three holes with a hand drill for the heli-coils?

Click to expand...

You can drill the holes with a drill but you need a guide plate to do it. I used to use a 2 inch thick iron plate with a hole drilled through it. Just make sure the hole is straight by boring it in a mill [or precision drill press]

Then I had a second hole that was tapped with the helicoil tap in a mill so it was straight. I used that to guide the tap straight into the head.

Don't even think about doing it by eye. Jim

Click to expand...

Helicoils or Time Serts?

I know the best solution is for you (Jim) to insert your own inserts after CNC work, but I am probably not going to send my head across the Atlantic, so I guess it is helicoil or Time Serts, which should I choose?

Here's a good older applicable thread that should help answer your question.
http://www.accessnorton.com/dang-pulled-out-head-stud-suggestions-please-t12741.html

SteveA said:

comnoz said:

pantah_good said:

I have a question about installing the CNW / ARP head mounting hardware. The three 3/8 studs require modifying the head with 3/8-16 heli-coils. I've done lots of heli coils by drilling for them with a hand held drill and never had a problem. The head looks to me like a difficult item to strap down to a drill press to "properly" tap drill those holes. Should I even be considering drilling those three holes with a hand drill for the heli-coils?

Click to expand...

You can drill the holes with a drill but you need a guide plate to do it. I used to use a 2 inch thick iron plate with a hole drilled through it. Just make sure the hole is straight by boring it in a mill [or precision drill press]

Then I had a second hole that was tapped with the helicoil tap in a mill so it was straight. I used that to guide the tap straight into the head.

Don't even think about doing it by eye. Jim

Click to expand...

Helicoils or Time Serts?

I know the best solution is for you (Jim) to insert your own inserts after CNC work, but I am probably not going to send my head across the Atlantic, so I guess it is helicoil or Time Serts, which should I choose?

Click to expand...

Time-serts are stronger if you can find them with a course thread on the OD.

A regular helicoil will hold better than a time-sert with a fine thread in the aluminum. Jim