Help ! 1972 mercruiser trim tab removal

[muskrat808]

Hi-replacing water pump for first time in 1972 140 hp mercruiser . Have all bolts loosened /removed except for the hex under the trim tab . Seloc manual and all internet postings say "remove trim tab " to access the hex nut, but how ? Does it pop off , unscrew or is there a nut /bolt I'm not seeing ? Thanks

 

[Don S]

Re: Help ! 1972 mercruiser trim tab removal

Just pop the little plastic plug out of the hole in the upper unit and use an allen wrench to get to the bolt.

 

[Bondo]

Re: Help ! 1972 mercruiser trim tab removal

Ayuh,... It's a 3/8" allen wrench, down through the hole above it....

If it's to corroded, a propane torch will melt it outa the way....

 

[ziggy]

Re: Help ! 1972 mercruiser trim tab removal

i soak mine with some pb blaster a few days prior to removal. then be sure ya got a good grip on the cap screw with the hex wrench. i usually put a lever (crescent wrench or the likes) on the hex wrench too.

 

[muskrat808]

Re: Help ! 1972 mercruiser trim tab removal

Thanks everyone . Bt the way what's pb blaster?

 

[ziggy]

Re: Help ! 1972 mercruiser trim tab removal

pb blaster is a rust/corrosion penetrant. like wd 40 (which is not a lub, but a rust penetrant too) but much better.
i use it on that bolt so i give myself the best chance of getting that particular bolt loose. i don't want to strip the drive of that cap screw down inside the drive. i remove that bolt yearly and it still goes 'snap' (when it breaks free of the trim tab) every year when it frees up to remove it.

 

[dpoff]

Re: Help ! 1972 mercruiser trim tab removal

I have found that before you put the allen wrench in, take a pick or small screw driver and poke around inside the bolt head to make sure that there`s no crud in there to make sure that you get a full bite when you go torque`n with the wrench.