Power head

[chris 1]

I have a 1987 Mecury 115 hp inline 6, How hard is it to remove the powerhead for a rebuild?

 

[sschefer]

Re: Power head

I have a 1987 Mecury 115 hp inline 6, How hard is it to remove the powerhead for a rebuild?

Intimidating the first time, easy the second. If you can, get the Merc Service manual for your engine and you'll breeze right through it. It takes me all of about 2 hours to have one off if I take the time to layout the parts as I remove them.

The most disturbing part is separating the PH from the exhaust plate. Don't beat on it, just try to rock it gently while hoisting it with moderate tension. This should break the gasket seal. I use a sharpened 1" wide putty knife placed carefully between the joint and gently tap it in with a small ball peen hammer. This will help to break it free but I cannot stress enough how careful you must be to not knick or otherwise damage the aluminum sealing surfaces. Small knicks can be fixed big ones will cost you. If the power head won't budge take another look for any bolts that you might have missed.

The most important thing you must do is to get yourself some zip lock bags and a sharpie. When you remove an assembly, place all the parts that you can in the bag and label it.

 

[Chris1956]

Re: Power head

Chris, You will want to remove the lower unit, wrap and top cowl, cowl support and starter. You will need some kind of hoist to pull the block straight up about 8 inches, to clear the studs of the midsection.

Your motor may have two mounting nuts in the front underside of the lower cowl. You may need to loosen them and then hoist the block an inch or so to get them off. The rest of the mounting nuts are under the u-shaped cowl that is under the bottom cowling. Disconnect the battery before starting this job.

If you are of average strenght, you should be able to lift the block by yourself, once it is off. You might pull the carbs, to protect them from damage.

 

[chris 1]

Re: Power head

Thanks guys this will be helpful to me. I have replaced auto engines and even my Mercruiser V8 but It seems challenging to work on outbord motors.