Mercury 135 not running

[trueno_13]

See this quite a few times with DIY repairs. Damages repaired but problem not fixed. Like a ol Chevy, ya fix the rusted rocker panel but dont address the drain hole which caused it to rust

Agreed.

 

[trueno_13]

I now have a doner engine that was runnig great, and the plan is to swap Powerheads, including all the bits attached to it (carbs, starter motor, solenoids, electrics, oil pump, etc.). But I want to make sure I do not run into the same issue again, so I am going to:
1) Change out the fuel line to be sure that air is not getting into the system and causing it to run lean
2) Change the impeller and gaskets in the lower unit
3) Check the plastic gear that drives the oil pump

Are there any other issues that may have caused the deterioration to the piston and ultimate failure that I should be checking?

 

[Chris1956]

You must be sure the carbs are clean and the timing is correct. Make sure you use the correct prop and the thermostats and poppit are working properly.

 

[Faztbullet]

Most likely cause was the idle stablizer/advance box. Chunk it and set max timing at 21°. A single cylinder running lean is a timing/fuel (carb) problem

 

[trueno_13]

the Powerhead swap out on my Merc 135 is progressing. However I have hit a snag. I have removed the 10 nuts that hold the power head on (some were well rusted and needed some WD-40 and a little persuasion). I am lifting the powerhead by the Eye Tool in the flywheel straight up, but the front section (under the carbs) will not separate. I can give a light pry at the back, and see a little separation up the sides, but the front will not let go.

Any thoughts or tricks I can try?

 

[Chris1956]

A lot of times the lift is not exactly straight up, or the motor is not parallel to the lifting. This causes the studs to bind in the midsection casting, along with any corrosion on the bolts. Leave some lifting pressure on the eye, and push on the crankcase next to the carbs with your hands to try to rock the front part of the block loose. This can straighten the pull and help the powerhead gaskets let go.

You can also trim the motor down a bit more to try and add some pull to the front of the powerhead.

 

[trueno_13]

Thanks for the advice, I have tried both and it just won't let go. I have been soaking the studs in WD-40 every night, but as I need to spray upwards, probably not getting the needed penetration. Is there something else that others use to try and remove corrosion from the studs?

Also, would putting some percussion on the block help break it loose?

 

[Dukedog]

if you have a good chain fall and/or motor hoist putpressure on it with it and then "shake tha livin' $hit out of it".....

 

[racerone]

???-----Drill into the exhaust housing from the side.----Start with a 3/16" drill.----Drill close to the block.----Get oil in there.-----If this fails go to bigger drill to cut the stud.----Been there done that.

 

[trueno_13]

???-----Drill into the exhaust housing from the side.----Start with a 3/16" drill.----Drill close to the block.----Get oil in there.-----If this fails go to bigger drill to cut the stud.----Been there done that.

So the old broken PowerHead has been removed, and it looks like I will need to drill into the donor one to get it separated.

 

[trueno_13]

I now have both powerheads removed, as well as the Exhaust and Transmission plate. Both have quite a bit of salt build up that I want to clean up. Any suggestions? Or do I just use INOX and a cloth?

Also, what will help soften the gaskets so that I can remove them in preparation for the new ones?