Head gasket replacement leak 90 h.p.

[Idlewildman]

Ok, so I just finished replacing my first head gasket on a 90 hp Yamaha. My problem is I have a very slight leak coming from one of the bolts.I have torqued it to specs and I even tightened that bolt a little more once I saw the drip and it still drips. I ran the motor on ears for about 20 min. and it showed two drops. What should I do? Should I remove all bolts and start over? I am worried I may strip out the threads if I go any tighter. Will this leak go away once the gasket has a chance to settle in? Not sure of my next move, please any suggestions are appreciated!

[ausnoelm]

Most leaks don't fix themselves, and usually just tightening bolts doesn't fix them either! There is a couple of possibilities, the gasket is broken, badly fitted or similar, the head is warped, the block is warped, or you just did something wrong! You didn't say where the leak is!

[99yam40]

bad spot in sealing surfaces or did not clean well.
did you use anything on the bolt threads?

[Idlewildman]

it is leaking from behind a bolt head, it is the bolt on the starboard side between the bottom cylinder and the middle cylinder. I used permatex aviation sealant.

[Idlewildman]

if I remove the head and check/clean the surface again, do I need to replace the gasket or can the old one be used? Should I put aviation sealant on the gasket before re-assembly?

[99yam40]

Never reuse head gaskets, need new every time you bolt back together.
pull the one bolt that is leaking and check to see if the hole is a blind one. (does not go into open water jacket).
may just need to seal the threads if hole goes into water jacket and not have a leaking gasket

[Idlewildman]

I am pretty sure all of the holes are blind holes. I am going to pull that one bolt and reseal just to see if that works before I pull the whole thing back down. Does a Yamaha OEM gasket have to face a certain way? When I looked at it I could tell no difference between the sides so I just put it on.

[Idlewildman]

OK, I removed the bolt that was leaking and re-coated it liberally with sealant and re-installed. I ran on flusher for 20-30 minutes and no leaks yet. I intend to run it this weekend and check for leaks. Should I re-torque the head bolts once I am able to run the motor under a load?

[robert graham]

Probably a good idea to check/re-torque all the head bolts after running the motor....

[ausnoelm]

Reapplying liberal amounts of "stuff" might stop the leak...for a while.