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Discussion Starter · #1 ·
Looking for advise, sympathy, ridicule what ever you got really.

Here's the deal. I'm using copper head and base gaskets that were treated with Permatex Copper Gasket Spray stuff on my CL350. I went with copper gaskets because of machining and wanting to have proper timing without having to degree the cam. Here is the discussion on all of that. http://www.hondatwins.net/forums/48-engine-discussion/46224-having-some-machining-done-cl350.html

The bike runs great! It just sort of bleeds. A lot. Mostly on the left side between the cylinder and the head, a little on the right and just a hair at the base gasket on the right. I've been through some re-torquing of cylinder studs I backed off and re-torqued one at a time with the top engine mounting bolts loose. Should I have backed off all then gone back and torqued them in the proper order? Do copper gaskets do better at more or less torque on the studs? How the heck can I torque the bolt the from the head to the cylinder? It's too freakin' tight to get a torque wrench in there now. I did use some Loctite and torqued to FSM specs. (Had one come loose one time)

I swear I was awake when I put this thing together and hell I've got a CB I put together a year ago it doesn't leak a bit with 2,500+ miles on the rebuild.

Thanks
 

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Have you got the dowels on the head studs fitted? Did they need O rings? If you have fitted them was their length reduced to compensate for the machining done on the head? Are they what's stopping your head seating properly? Just some thoughts....
Nigel.
 

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Discussion Starter · #4 ·
All dowels are in their proper place, no o-rings other than the two big ones on the cylinders. The gaskets used are thinker than stock and really are just adding back what was taken away. I rebuilt two of these motors at the same time and found NOS cylinder studs for both. The rubbers, for lack of a better term that are fixed to the front two outside studs are there and completely intact.
The goal of using the copper gaskets in thicker dimensions was so the cam timing would not be affected as earlier stated. I would then assume all heights, clearances or distances are basically correct especially looking at how the cam lined up during assembly. image.jpeg

Not sure if that torque wrench adapter would work or not since the bolt is kinda recessed and of course since I used a stainless steel allen it definetly will not. Thanks though could be handy for something.

Thanks for the thoughts. Keep em' coming.

image.jpeg image.jpeg
 

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It sure looks pretty, but why are you using copper gaskets again? I have no experience with them but I believe they need perfect surfaces on the head and cylinder block. This is even better than what you can get with a fly cut skim on the surface. The Goldwing guys recommend lapping the heads in with a piece of plate glass, fine wet or dry paper and an oil. You should see an even dull finish on the surface. Next make sure the gasket is from annealed copper and has only been used once. You may want to talk to the gasket supplier, or go back to a stock head gasket...
 

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Discussion Starter · #6 ·
Went with copper due to changes after some machining which allowed me to select thicknesses to match what material was removed. Machining was needed to fix what PO had done to the gasket surfaces. I went with these gaskets based on recommendations by crazyPJ gaskets were purchased here CGU Home Page

I've spoken with a friend who's family owned a Honda dealership for many decades. They raced 750's big time back in the day. His experience with copper gaskets is that they are not the best at NOT leaking. He did however recommend re-torquing the cylinder studs and bolts that go from the head to cylinder. He did NOT recommend loosening anything other than the top engine mounting bolt. He also suggested going through the torquing process while the engine was warm and to go one foot pound more than max as per FSM, so 15.5 ft. lbs. I've done all that and will go back through the valve clearances, timing, and cam chain tension then give it a go.
 

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Once a copper gasket has been torqued it becomes hard and must be annealed (Softened) before trying again. I would lift the head remove the gasket then lower the head back on loose and see if you can see light between head and barrels. Looking at your pictures it looks like one of the liners is higher or lower than the other and has not been machined flat!! Use a flat edge (Steel ruler) across the top of the barrels to make sure they are flat. Have fun ;)
 
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