Cylinder head leak

R

Rusty_Nail

Active Member
Just installed this high compression head and it's leaking from the corner circled. The head bolts are torqued down as much as I can get them without stripping anything out, but it still leaks after I go for a ride. What can I try to fix this? It has a copper head gasket too.
 

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I know the head is new But... Check the head deck and cyl deck for flatness

Rub the head and cyl deck on sand paper and plate glass to ensure they're flat

Tip: mark up the sealing surfaces with a black sharpie pen
When the sharpie marks are sanded off you know it's flat

BTW head bolt torque is 12 ft lbs

Anneal copper head gasket and reuse it
 
Ok. I'll have to wait until next weekend to mess with it, but I'll try that idea. I'm pretty sure it's not a exhaust gasket leak since I just put a new exhaust gasket on it yesterday, but not completely ruling that out either. But when I run my finger under that corner of the motor, I get enough oil on my fingertip to completely cover it. Also when I pulled the plug to check it the tip is like an ash grey color.
 
Hey guys, didn't mean to post here after so long, been working a lot. I'm going to plan to try decking the head this weekend. Forgot what grit or grits of sandpaper I should use? Thanks!
 
Start with 120 grit until flat Then switch to 220 to make it smoother
Some suggest to keep going with finer sandpaper but IMO 220 is enough

While sanding brush off the aluminum dust from the sandpaper about every 20 strokes
Ya don't want the dust to pile up on the sandpaper because it will cause the surface to become uneven
Don't use sandpaper that's been folded or kinked, the fold or kink will make the surface uneven - Use new sandpaper
 
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Ok. but use a fresh sheet of sandpaper each time? And would you recommend using some kind of oil on the sandpaper? Is it better to do it with the sandpaper wet or dry? Never decked a head before so want to make sure I do it right and don't take off too much material and wind up having to buy a new head. Thanks!
 
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