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TOPIC: Need help dropping L/U Merc 650

Need help dropping L/U Merc 650 15 years 1 month ago #8507

Folks - I'm asking this before I damage something.

this is a 1967 thunderbolt 650

I removed the trim tab and removed the bolt underneath

Removed the nut from the forward stud - the one just behind the reverse tilt lock.

Removed 2 bolts under the 'cav plate above the propeller.

Loosened the 2 nuts on either side of the motor tower to L/U flange

Can only get the gearcase to drop 1/8"

Tried placing shift lever in F, R, N,

Tried pushing up on tilt latch

All to no avail

I replaced the powerhead on this very engine 3 years ago ( I did not drop the lower) I put a new o ring on the drive shaft & I coated the driveshaft splines with never sieze.

What the hell am I missing?

Please help before I feef on the thing & bust it.

Bruce.

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Re:Need help dropping L/U Merc 650 15 years 1 month ago #8509

  • MarkS
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BG, we all know I'm no master mechanic, but here's a trick I had to use on the 63 Merc 700 first time I pulled the lower. I used a rubber mallet in downward blows (alternating sides) against the gearcase (fat round part). The splines weren't holding it in, it was corrosion around the studs sticking thru the mid. Might be worth a try....

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Mark

Re:Need help dropping L/U Merc 650 15 years 1 month ago #8511

cut yourself a couple wood wedges, and use them to split them apart

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Re:Need help dropping L/U Merc 650 15 years 1 month ago #8514

I put a bunch of washers on top of those 2 studs on either side of the motor tower to L/U flange, then turn the nuts into them. Ooops! Pop goes da LU!

Der ain't nuttin else der, so ya got all da fasteners off, jest go gentle like...

Frank

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Re:Need help dropping L/U Merc 650 15 years 1 month ago #8529

most likely the shift shaft is rusted together take a torch and heat the coupling with wedges puting pressure on the lower unit down.

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Re:Need help dropping L/U Merc 650 15 years 1 month ago #8545

MadProps wrote:

cut yourself a couple wood wedges, and use them to split them apart


Concur...

Be careful beating on any part of the lower with a mallet...those old castings can be pretty frail and you'll snap off parts of the cavitation plate, or worse, quite easily!

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Re:Need help dropping L/U Merc 650 15 years 1 month ago #8630

thanks for the response folks. As I had suspected - I'm going to have to get rough with this thing.

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