Broken Head Bolt 1990 4hp E4RESR.

cprodave

Petty Officer 1st Class
Joined
Jul 1, 2012
Messages
301
While fixing a compression problem (90psi Upper but only 45psi Lower cylinder) I broke off one bolt. I was using a manual Impact Driver--got 5 bolts out successfully, the 6th bolt was moving slightly with the Impact Driver but in haste (even after lubricant soaking a day or two) I switched to ratchet with steady pressure--that's when it broke. Should I have stayed with the Impact Driver? Also I probably should have heated Engine Block with my microtorch...
So now I have this bolt sheared-off within the unthreaded thru-hole in the Head. Fortunately it is not sheared off within the threaded section of the Crankcase/Cylinder Block because this gives me 2 options. I thought about using an Easy-out/Extractor, but would probably be better off using Visegrips (and torch this time) if I can separate the Head from the Block. But the Head is stuck to the block. I am unsure if previous owner used Permatex etc or if Head Gasket can create firm adhesion Head-to-Block.
I am thinking of wedging single-edge razor blades at the Head Gasket . Or is there a better technique without damaging the 2 mating surfaces?
Thanks in advance.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,881
??----Rotate the cylinder head and it will come off.------Use heat on the block where that one bolts is stuck.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Was the motor used in fresh or salt water ? Salt can seize up any bolt's thread badly that will eventually break when removed....(bad music)

Happy Boating
 
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