tiny water drops on spark plug but plug is not white indicating head gasket leak

bonitoman

Petty Officer 1st Class
Joined
Jul 9, 2002
Messages
292
My compression is 135 on all 4 cyl on my 92 130 with 10 hours on my rebuild. Engine runs great at 55 mph 6 grand on the tach. Usually a plug gets cleaned from a head gasket leak. This #4 plug looks nice and tannish brown like the others. I did notice tiny water droplets. It is only on #4. Any suggestions. Thanks
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: tiny water drops on spark plug but plug is not white indicating head gasket

Re: tiny water drops on spark plug but plug is not white indicating head gasket

Only two concievable sources I can think of for water intrusion.One is contaminated fuel ,which one would think to be evident in more than one cylinder and the other is a leaking head gasket or exhaust cover gasket.<br /><br />Edit: I guess that's 3 concievable possibilities. ;)
 

bonitoman

Petty Officer 1st Class
Joined
Jul 9, 2002
Messages
292
Re: tiny water drops on spark plug but plug is not white indicating head gasket

Re: tiny water drops on spark plug but plug is not white indicating head gasket

Could it be the aftermarket head gaskets and gasket set that I picked up for the engine. I have always used these on omc engines. Are yamahas any different?
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: tiny water drops on spark plug but plug is not white indicating head gasket

Re: tiny water drops on spark plug but plug is not white indicating head gasket

I don't know.If it is a head cover gasket ,it may be due to a surface deformation .If you remove the head covers,try contact checking them without the gasket using some prussion blue.I assume they were torqued to the proper value and in sequence.
 

Justin H

Cadet
Joined
Jan 26, 2004
Messages
22
Re: tiny water drops on spark plug but plug is not white indicating head gasket

Re: tiny water drops on spark plug but plug is not white indicating head gasket

You might check the exhaust plate. I had a Yamaha same problem replaced the head gasket and cover no help. Pulled the exhaust plate and found a pin hole in the plate allowing water into the cyl.<br /><br />Capt. Justin
 
Top