Seized Mercury 50hp thunderbolt red band

[briaineo]

Have a question about a Mercury 50hp I picked up, was advertised as for parts or repair, the wiring is in excellent condition and overall was much better than I expected before collection, 3 cylinder.

With the plugs out and looking into the plug holes what should I see? Cylinder No. 1 is very far back (maybe 3 inches) and No. 2 about 1 inch back and Cylinder 3 maybe 1/4 ways back.

Does this sound correct? Or should all the pistons be evenly spaced from each other? Hoping a piston rod is not bent or broken.

At the moment I have penetrating oil in the cylinders and will remove the lower unit tonight.

 

[Chris1956]

Pull off the transfer covers and you will be able to see the damage.

 

[Chinewalker]

For clarity's sake, what is your serial number? To my knowledge, the Thunderbolt trademark was no longer in use when they went to a 3-cylinder 50hp. True "red band" 50s were built in the late 1960s and early 1970s and were 4-cylinder models.

As for being seized, are you sure it's in the powerhead? More than a few times, I've dropped a lower unit off to find the powerhead miraculously freed up!

 

[racerone]

Not all the pistons end up at the top of the cylinder at the same time !!!!!