2002 4.3 merc

[zuki88.5]

spring start up ...replaced plugs, new starter , checked compression ..
# 1 # 3 # 5 all about 126
#6 125
#2 78
# 4 100
sprayed with wd 40 and sat overnight
checked compression again
#2 78
# 4 0 checked twice
added straight oil to both low psi cyl,
will sit for 24 hrs and recheck .
my thinking now is that i my have a cracked head from winter
I invite any input in the mean time
thanks

 

[bondo]

Ayuh,..... Never seen a cracked head cause a lack of compression,.....

Pressurize the cylinders at Tdc to see if it's valves, or rings,....

 

[fastjeff]

Or a blown head gasket.

Jeff