leaky head gasket

[johnntab]

A friend and I have recently rebuilt a 1974 9.9 evinrude. We replaced all the gaskets and piston rings, and cleaned up all the moving parts. The problem is that now the plugs come out really clean (probably water in the cylinder) and we have a little leak around the outside of the head. As I said earlier we replaced the head gasket, but we cant get it to make a good seal. What can we use to get a better seal? Thanks for your help, we learned how to rebuild the motor from your info.

 

[G DANE]

Re: leaky head gasket

You have to get a new gasket. When you have the head of, try to hold a steel ruler against it and see if it is bent a bit by heat. If it is it has to be grinded with nr. 400 sand paper laid against a straight surface. Remember to tighten to the right turque, warm the motor up, and retighten to same turque. It will make a good seel then.<br />If you are not sure how to gring the head - ask again. Good luck

 

[G DANE]

Re: leaky head gasket

Oh and one thing more:<br /><br />When you tighten and retighten, start with the center bolts moving outwards. Be carefull when grinding, place sandpapir on a thick steel plate or glassplate, and drag the head over it. Maybe someone else can give you further advise.

 

[johnntab]

Re: leaky head gasket

thanks g dane, we will check that out. Is there some kind of sealant we can use to help the gasket seal better?

 

[petryshyn]

Re: leaky head gasket

Yo bass man:<br />Are you sure its the head gasket leaking, not the water jacket cover.....<br /><br />Here's a little tip to resurfacing the head.<br />>Get a sheet of medium emery cloth<br />>masking tape or duct tape it down on a smooth surface (piece of glass, steel, good arborite table)<br />>grab the head in the middle with both hands, and rotate the head in a figure 8 fashion until all machined surfaces on the gasket side have been touched (resurfaced) You'll know this when all surfaces are shiny. The amount you have to sand off will tell you the amount the head was warped....After every couple of figure 8's made, remove head from paper and clean paper with compressed air.(safety glasses please) You may need to use more than one sheet if head is warped really bad. Once you're satisfied that all surfaces are touching, finish off with a few more figure 8's on a fine piece of emery cloth. I do this on every head removal. I use a machinist's straight edge to check, but visual is good enough.<br /><br />Don't do this to the head cover if any. It's so badly warped we'll rely on the bolts to pull it back in. You can do this to the other side of head if applicable. BE SURE TO CLEAN HEAD thoroughly when done. Any emery left in or on head will score the cylinder walls and reck your nice engine. Don't use emery cloth on the block for this reason. Keep it away!!!Torque the bolts in the recommended pattern, and in 2-3 sequences or torque levels.<br /><br />5____6<br /><br />1____2<br /><br />4____3 <br /><br />You should have a manual. Use no sealer if stated on head gasket.<br />Good luck! <br />