well i thought i blew my #3 cyl sunday so i pulled the head tonite to take a look. heres what i found this cylider had 17bs comperssion and was dry the head gasket looks blown to me and the side of the head as you can see in the pics is wet, the cylinder looks to be in good shape no scratches or gouges and piston is intact and looks like the others could this be my problem? and what would cause a blown head gasket. i may be getting my hopes up for this but need opions here. thanks guys

if the piston and cyl. look alright try replacing the head gaskets (both of em) and see what the comp is.
head gasket would cause major loss of compression, with the heads off both cyls. try turning it over by hand and listen closely for any sounds that don't sound right before reassembly to see if the piston has any probs.
that is my best recomendation but I am not a marine mech.

I would try gaskets first.

That was your problem, I can 99.99% guarantee after seeing it. Turn the engine over by hand ( take the other plugs out too !)...and take a look at the cylinders. If all is well, then clean that head up, and replace the gasket.

When I did mine, I took a piece of glass from an old photo frame, dabbed some fine valve grinding compound on it. ( in the little green can with 2 lids)....placed the head on it and worked it around in a figure 8 pattern to smooth out any imperfections. Clean it off well...( rinse it) and reinstall it with the new gasket. If that's a 6 cylinder engine....go ahead and do the other gasket too. Torque the head bolts according to the factory specs ( and pattern)...run it a little and then re torque them.

You may have dodged a bullet, my friend. Consider yourself lucky...because water doesnt compress.

I would be jumping with joy! Find a motor machine shop in your area to check the heads for any warpage. Cylinder heads need a rough finish to hold the gasket properly.

use a dial indicator to check the rise of the piston to make sure it's coming all the way up too

just got it put back together comp. readings are 119-128 and ran good on the ear muffs in the driveway. it will get a lake test at twok tomrrow evening lets pray it stays together

Did you do both sides?

yes i did both of them. put the heads in a parts washer to make sure they were good and clean. cleaned the block really well ( used a parts cleaning fluid not water) and wiped it down several times. once the compression checked out i put the pulgs in and started on the first try i guess we will see what it will do under a load if i get off in time to take it out keeping my fingers crossed on this one. it was the first time ive been inside a outboard motor i dont think i would want to go past the heads look confusing after that.

Dont forget to re-torque the heads after you run it a little.

lucky dog...

well it looks like i might have dodged the bullet this time i ran it for about 30-45 minutes around millcreek tonite. if you were on the millcreek tonite and wandering waht the guy in the maroon and gold astro was doing it was me. got it home re-torqued the heads and i am hoping all of this is behind me for now. thanks for all the help old frog i really do apreciate it.

Dont thank me. Thank the pros on here. I got a lot of my info from them..being that Yamaha bikes are a bit different than outboards...I've had to soak up all they tell people.

Just pass it on.

I think I may have the same problem but I am no way qualified to work on my motor lol