Removing Cylinder Head Bolts and Cover Bolts on a 1986 Johnson 150 HP (J150TXCDC)

[Terrapin]

After additional research on this site I believe my cooling system deflectors may be causing an overheating condition. I am now getting an overheat warning only when I run over 4,000 RPM. I replaced the water pump, thermostats, pressure release valve, and springs, two years ago, and believe they should be in good condition. The thermostat cover bolts came off without any problems.

I am looking for guidance on the best method to removing the cylinder head cover bolts and the 14 cylinder head bolts associated with each cylinder head. I would like to replace the cooling system deflectors. Is there a best demonstrated practice to successfully remove these bolts on a saltwater engine without breakage? For example, PB Blaster soaking, tightening slightly then loosening, a slight impact blow to each bolt prior to loosening, or using heat? I plan on attacking this at the end of the season as I don?t want to lose any water time this summer.

Your help is greatly appreciated.

 

[oldboat1]

think the answer is all of the above as needed, along with a little prayer. I would start soaking the bolts while still running the motor -- can't hurt, and might help (heating and cooling cycles with normal use). Actually, they might ease out just fine. Always hard to predict.

 

[jakedaawg]

Personnaly i use a low volt electric impact to shake them loose. I start with a 7.2 volt and let it run till the batteru goes. If that doesnt do it i use a 14 volt.

You can also do this with an air impact by installing a pressure regulator before the gun.

The key is to.let the impact work, just pull the trigger and let it shake.