Installing an Atlas Head with Engine In Frame

Hi All
Hate to ask what may be a stupid question but here we go. I've been building my Atlas project in the frame on it center stand. Presently the barrel is on with pistons installed and bolted down. My next step is to install the head. I am using a solid copper head gasket and will Pliobond it down. I did a dry run with the push rods all the way up in the head after tiling the head back. Next I found it impossible to tilt the head forward enough to allow the push rods into their respective barrell tunnels primarily I think because I had the three 3/8" studs installed in the head already. What's the approach? Should those studs be installed up through the barrel after the head is on ? Thanks

Sometimes it takes a little tilting left or right up between the frame rails. Maybe try it without the push rods to get your angle kind of figured out. Leaving the tappet covers off and studs out gives you some extra clearance. The studs you mentioned should be in the head.

HMMM will have to try it again

Getting the head on a Norton twin engine in the frame is one of those things you have to figure out for yourself. Just have to keep trying until it drops into place. Difficult to explain the exact steps that would work for you. One of those rite of passage exercises. That's my twisted opinion having done it a half dozen times, but only in a P11 frame. Somebody that does it 10 times or more per year in featherbed frames might have a better handle on the exact process.

Only thing I know for sure is it is actually easier to assemble a Norton twin engine on the bench and move the lump into the frame whole with the head on. Heavy for sure, but easier than fussing with the push rods while navigating around the frame rails.

Watch out with the Pliobond. It won't let you move the head once the head makes full contact with it.

The 3 studs must be in the head. All part of the fun. Don't forget to put the two little studs in the barrels in front of the pushrod tubes before dropping the head down.

Thanks Schwany. Just curious what you use for a head gasket and sealant if any?

I have used both Copper and composite. Conventional wisdom suggests copper does not blow out, but tends to leak oil. Composite has to be torqued and re-torqued or it may blow out, but is generally more oil tight. Regardless of type: Torque when installed, re-torque after first run, re-torque after 100 or so miles and torque again at 1000 miles. Then maybe every 2000 miles or so thereafter. I have never used sealant other than a bit of Hylomar Blue around the pushrod tubes at the front, for me at least I think it makes too much mess to clean up at a later date. I prefer the composite type on Norton's. If you keep up with the re-torques they seem to seal very well. Copper of course prefer's smoother mating surfaces, not always that easy to achieve with the sometimes rather poor engineering tolerances on some British bikes.

In regards to fiddling around with the pushrods to put the head on in the frame. It is a bit of a pain, but gets easier after you have done it several times. One thing that helps is learning how to get the pushrods as far as possible into the head. Then while holding the pushrods in the head, put the head onto the barrels, let the pushrods fall into the guides and roll the head forward into place. As you start to tighten the head bolts be careful to make sure the pushrods have seated correctly. Getting them to mate correctly with the rockers tends to require a fair bit of patience.

I have only used that copper spray for head gaskets.

As mentioned above, a kind of rolling motion is what I have used, and get the push rods up in the head past the rockers. Once you get the push rods to fall into the tunnel with the correct long/short rod orientation - you’re in the home stretch. I haven’t had a rod that didn’t fall into place at the lifter, not to say it can’t happen. Loosen up your adjusters on the rockers as much as you can and use a pick to move the rods under the rockers. Then tighten them down a bit to keep the rod in place.

jms said:

Thanks Schwany. Just curious what you use for a head gasket and sealant if any?

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I used Pliobond once with a copper head gasket. It definitely holds parts together. If I were to use a copper head gasket again, I would spray both sides of the copper gasket with a copper spray sealant. I haven't tried that yet on a Norton engine, but have on small displacement auto engines and it does work.

I'm currently using a composite head gasket. I'm not using a commercial head gasket sealant. I'm using aluminum brush on paint on the head surface and barrel deck. I do not suggest using the aluminum paint. It is very old school and works better with a copper head gasket if the head and deck are perfectly surfaced. Only benefit to using aluminum paint is the head comes off easy and the paint is not difficult to clean off the head or the deck. I do retorque either type of head gasket, but as mentioned the composite definitely needs it a few times.

If the head and barrel surfaces are flat, you won't have any problems. I would not install a head gasket on an old Norton engine without some type of sealant myself even if the head and barrels were freshly resurfaced. That is how much I don't enjoy R&Ring the head with the engine in the frame and only having two arms and two hands.

Schwany said:

I used Pliobond once with a copper head gasket. It definitely holds parts together. If I were to use a copper head gasket again, I would spray both sides of the copper gasket with a copper spray sealant. I haven't tried that yet on a Norton engine, but have on small displacement auto engines and it does work.

I'm currently using a composite head gasket. I'm not using a commercial head gasket sealant. I'm using aluminum brush on paint on the head surface and barrel deck. I do not suggest using the aluminum paint. It is very old school and works better with a copper head gasket if the head and deck are perfectly surfaced. Only benefit to using aluminum paint is the head comes off easy and the paint is not difficult to clean off the head or the deck. I do retorque either type of head gasket, but as mentioned the composite definitely needs it a few times.

If the head and barrel surfaces are flat, you won't have any problems. I would not install a head gasket on an old Norton engine without some type of sealant myself even if the head and barrels were freshly resurfaced. That is how much I don't enjoy R&Ring the head with the engine in the frame and only having two arms and two hands.

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Thanks all good insight

jms said:

Thanks all good insight

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Well got the head on and push rods seated. I decided to use a Flame Ring head gasket and decided against the copper HG and Pliobond. Glad I did because by the time I got it on and the pushrods sorted out, the Pliobond would have really been a problem. Not sure how people actually use the Pliobond. It seems that it would require perfect placement of the push rods as you drop the head on the barrel. No second chance

kernel65 said:

I have only used that copper spray for head gaskets.

As mentioned above, a kind of rolling motion is what I have used, and get the push rods up in the head past the rockers. Once you get the push rods to fall into the tunnel with the correct long/short rod orientation - you’re in the home stretch. I haven’t had a rod that didn’t fall into place at the lifter, not to say it can’t happen. Loosen up your adjusters on the rockers as much as you can and use a pick to move the rods under the rockers. Then tighten them down a bit to keep the rod in place.

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It can happen. That is my #1 worry when I install a head. I have two wooden blocks to support the head while I make sure the pushrods are located in the lifters. Then I set the head down and make sure the pushrod is located in the rockers. I use the four outer head bolts to secure it and CAREFULLY turn the motor over with the drive side crank nut and a 1/2" ratchet. At this point I turn the radio off so I can hear anything that isn't right. And CAREFULLY feel for any resistance while turning it over...like two valves touching. This is difficult to determine because of valve spring pressure. At this point I also try to set valve lash at about .010. Now, cross your fingers and turn the motor over very slowly while watching the rockers and feeling for resistance. It takes very little turning pressure to bend a valve. In that case a loud SNAP will let you know that everything just went south. It often takes the guide with it...Next problem....the guide is then bell mouthed and difficult to remove.