Oil leak at the head gasket

dobba99 said:

Jim, Many thanks for the info, much appreciated.
What i meant by my last sentence was has anyone tried the belleville (Live Loading) washers under the head bolts?

Regards
Peter

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Yes, I have tried them also. It takes several of the washers in the size I could find to handle the clamping force.
That reduced the thread engagement on the bolts enough that I didn't like the result. Jim

Sure are pretty, think I'll buy an extra set and mount them in a frame.
thanks Jim and Matt for help keep these beast running.

MS850 said:

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How does that '63 McLane handle?

grandpaul said:

MS850 said:

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How does that '63 McLane handle?

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Hehehe, I put that on my list of bike awhile back, you're the first to comment, congrats. In about 1964 i went with my dad to downtown Compton to buy it. It's been running good ever since. Not even one head re-torque. I'm actually considering restoring.

MS850 said:

I'm actually considering restoring.

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Channel hobot:

gortnipper said:

MS850 said:

I'm actually considering restoring.

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Channel hobot:

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That will give me an edge, or put me over the edge , Ill definitely will edge out the competition.

jim did a set for me before they were for sale and I have to say the first heat cycle and re-torque was VERY in lighting. it was not till about 5 heat cycles and test rides till I had movement in a re-torque and than is was minimal where with stock bolts 1 heat cycle and the bolts was almost finger tight.sure looks like these bolts are the answer to help stop head gasket failures.

MS850 said:

Sure are pretty, think I'll buy an extra set and mount them in a frame.
thanks Jim and Matt for help keep these beast running.

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bill said:

jim did a set for me before they were for sale and I have to say the first heat cycle and re-torque was VERY in lighting. it was not till about 5 heat cycles and test rides till I had movement in a re-torque and than is was minimal where with stock bolts 1 heat cycle and the bolts was almost finger tight.sure looks like these bolts are the answer to help stop head gasket failures.

MS850 said:

Sure are pretty, think I'll buy an extra set and mount them in a frame.
thanks Jim and Matt for help keep these beast running.

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Wow thats great to here, re-torquing the head is a nuisance to me. It will be like my 73 CB500, slap the head and ride.

I am NOT saying that a re torque sequence is not needed or recommended but that it is not as drastic a change when using stock type hardware. IMHO i would still do a re torque in the first hundred miles and again at 500 with a valve reset. this is my first experience with these bolts and I prefer to err on the side of caution. also a re torque is a lot less hassle than to replace a head gasket. maybe jim can chime on his recommendations as to re torque's

quote="MS850"]
Wow thats great to here, re-torquing the head is a nuisance to me. It will be like my 73 CB500, slap the head and ride.[/quote]

bill said:

I am NOT saying that a re torque sequence is not needed or recommended but that it is not as drastic a change when using stock type hardware. IMHO i would still do a re torque in the first hundred miles and again at 500 with a valve reset. this is my first experience with these bolts and I prefer to err on the side of caution. also a re torque is a lot less hassle than to replace a head gasket. maybe jim can chime on his recommendations as to re torque's

quote="MS850"]

Wow thats great to here, re-torquing the head is a nuisance to me. It will be like my 73 CB500, slap the head and ride.

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[/quote]

In my testing I did install a new copper gasket and rode 2500 miles without checking and with no oil leakage.

I would still recommend at least 2 retorques when new and rechecking every 10,000 miles or so.

I am sure that maintaining good clamping force will be much more forgiving with the waisted bolts but I am not ready to say no retorques will be needed.

I would rather be safe than sorry. jim

comnoz said:

bill said:

I am NOT saying that a re torque sequence is not needed or recommended but that it is not as drastic a change when using stock type hardware. IMHO i would still do a re torque in the first hundred miles and again at 500 with a valve reset. this is my first experience with these bolts and I prefer to err on the side of caution. also a re torque is a lot less hassle than to replace a head gasket. maybe jim can chime on his recommendations as to re torque's

quote="MS850"]

Wow thats great to here, re-torquing the head is a nuisance to me. It will be like my 73 CB500, slap the head and ride.

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In my testing I did install a new copper gasket and rode 2500 miles without checking and with no oil leakage.

I would still recommend at least 2 retorques when new and rechecking every 10,000 miles or so.

I am sure that maintaining good clamping force will be much more forgiving with the waisted bolts but I am not ready to say no retorques will be needed.

I would rather be safe than sorry. jim[/quote]

Ill be re-torquing the head, but sounds like wont be continually re-torquing the head, maybe just once.

comnoz said:

... something that seems really obvious in hindsight ...

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The hallmark of good engineering.

I was so taken with Jim's work that I decided to try reducing the shank size on some fasteners. These are a set of 850 through bolts that I turned down on the lathe, and then polished with emery cloth strips. I tried using my tool post grinder, but didn't get any better finish than with a circular carbide insert in the lathe. I may give grinding another try with some new wheels. these are 5" bolts that still have to be cut down to length for the Norton. I'm saving them for an iron barrel engine, where they don't show. For the Maney cylinders, where the bolts are exposed, I'm planning to pick up some stainless bolts from ARP, and see if I can do a similar modification to them. I'm also planning to do a set of stainless head bolts, starting with ARP bolts. I'd use CNW bolts, but they aren't the right thread for the Maney cylinders.



Always fun to find something new to play with.

Ken

lcrken said:

I was so taken with Jim's work that I decided to try reducing the shank size on some fasteners. These are a set of 850 through bolts that I turned down on the lathe, and then polished with emery cloth strips. I tried using my tool post grinder, but didn't get any better finish than with a circular carbide insert in the lathe. I may give grinding another try with some new wheels. these are 5" bolts that still have to be cut down to length for the Norton. I'm saving them for an iron barrel engine, where they don't show. For the Maney cylinders, where the bolts are exposed, I'm planning to pick up some stainless bolts from ARP, and see if I can do a similar modification to them. I'm also planning to do a set of stainless head bolts, starting with ARP bolts. I'd use CNW bolts, but they aren't the right thread for the Maney cylinders.

Always fun to find something new to play with.

Ken

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Ken, how about making more than one set for Maney cylinders?

I'd certainly buy a set from you sir...

Perhaps they never need to be retorqued but they are inaccessible once the head is on so
waisted bolts here might be worth it.

Onder said:

Perhaps they never need to be retorqued but they are inaccessible once the head is on so
waisted bolts here might be worth it.

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Indeed. And even more important on an alloy barrel, I would imagine, as alloy is surely more likely to 'crush' than iron.

While these bolts look lovely, it seems unnecessary on an iron barrel. Might be a Good Thing on an alloy barrel, but are the Maney castings not done in a really good alloy whic hdoes not have the crushing problems of the Norton head?

I suspect that the need for good flow in the very complex head casting dictated the composition of the alloy rather then the more normal procedure of speccing according to the loading.

I'm also in the queue at cNw for a set of Matt's (well, really Jim's) head art .

/Steve.

Actually the stock Norton 850 barrel fasteners are built with a long threaded section to provide some extra stretch.

I use the stock Norton through bolts when I build a motor with Maney cylinders. I have found they are less likely to pull the threads in the cases.

Waisted bolts in the aluminum barrels would be even better although I worry about waisting a hardened bolt in a lathe due to stress risers. Jim

comnoz said:

Actually the stock Norton 850 barrel fasteners are built with a long threaded section to provide some extra stretch.

I use the stock Norton through bolts when I build a motor with Maney cylinders. I have found they are less likely to pull the threads in the cases.

Waisted bolts in the aluminum barrels would be even better although I worry about waisting a hardened bolt in a lathe due to stress risers. Jim

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All good points. I wonder a little about the effect of turning them on a lathe, in terms of stress risers. Once I found the right combination of speed and feed, and established the depth of cut needed to keep from rubbing instead of cutting, which work hardens the surface, I was able to get a pretty smooth finish. Using a coolant also helps a lot. But there are still very fine machining marks left, even after polishing, and I'm not sure if they are a risk. With a little research, I'm sure I can sort that out. And I'm still experimenting with the tool post grinder to see if I can get a better surface finish. Like I said, this is just an experiment. I'll see if I can talk to one of the engineers at ARP about it. I'm hoping I can get to them tomorrow. I still need to pick up some of their stainless bolts to work on.

I'm using these bolts instead of the stock 850 bolts because I have a large box of them on hand. Back when I was importing and selling the Robertson alloy cylinders, I needed to supply six through bolts with each cylinder, and buying that many stock bolts was kind of expensive. So I bought a couple hundred of the 5" Holo-Krome bolts and shortened them to the stock length. Now I'm just using them up. The stock bolts probably are a better choice because the added thread length does allow more stretch. But I've used a lot of these shortened bolts over the years with no problems, so I don't worry too much about it.

I think properly done waisted bolts and studs for both cylinders and heads are the best way to go, and that's what I plan to use from now on. The only question now is whether I can make them properly, or if I need to have them made. Where quality stuff is already available, like the CNW head bolts, I'll cheerfully just buy them. But for other applications, like the Maney head bolts, and through bolts for shorter cylinders, I still have to sort out how to acquire them.

Is CNW going to offer the through bolts in a waisted, stainless version?

It's all your fault, Jim. You're the one that got me thinking about this subject.

Ken

[quote="lcrken"

All good points. I wonder a little about the effect of turning them on a lathe, in terms of stress risers. Once I found the right combination of speed and feed, and established the depth of cut needed to keep from rubbing instead of cutting, which work hardens the surface, I was able to get a pretty smooth finish. Using a coolant also helps a lot. But there are still very fine machining marks left, even after polishing, and I'm not sure if they are a risk. With a little research, I'm sure I can sort that out. And I'm still experimenting with the tool post grinder to see if I can get a better surface finish. Like I said, this is just an experiment. I'll see if I can talk to one of the engineers at ARP about it. I'm hoping I can get to them tomorrow. I still need to pick up some of their stainless bolts to work on.

I'm using these bolts instead of the stock 850 bolts because I have a large box of them on hand. Back when I was importing and selling the Robertson alloy cylinders, I needed to supply six through bolts with each cylinder, and buying that many stock bolts was kind of expensive. So I bought a couple hundred of the 5" Holo-Krome bolts and shortened them to the stock length. Now I'm just using them up. The stock bolts probably are a better choice because the added thread length does allow more stretch. But I've used a lot of these shortened bolts over the years with no problems, so I don't worry too much about it.

I think properly done waisted bolts and studs for both cylinders and heads are the best way to go, and that's what I plan to use from now on. The only question now is whether I can make them properly, or if I need to have them made. Where quality stuff is already available, like the CNW head bolts, I'll cheerfully just buy them. But for other applications, like the Maney head bolts, and through bolts for shorter cylinders, I still have to sort out how to acquire them.

Is CNW going to offer the through bolts in a waisted, stainless version?

I talked to an engineer at ARP a little while back. He said any cutting or polishing on the shank of a high tensile bolt should be done lengthwise -just like polishing a con rod.

I don't know how much of a problem cutting around the bolt would create, but if I were going to be selling them I would follow that rule.

We may have to look into some waisted barrel bolts but they would probably be in 180,000 psi black oxide since they don't show and the price would be much more reasonable. I am sure it would cut down on barrel distortion and the tendency to pull the case threads which does happen on racebikes from time to time. [ie, Kenny's bike at Willow a couple years ago -with the kit bolts]. Jim




Ken[/quote]