Mercruiser Trim Cylinder End Caps Breaking!

CruisermikeT

Recruit
Joined
May 22, 2012
Messages
1
Since I'm new on here, I don't know if this has been discussed before, but I couldn't find anything in other areas so here goes...

I bought a 1980 Century walk-thru, with a Mercruiser 485 4 cyl. I/O. This is not my first boat. I'm a pretty good mechanic, but I'm having an issue that I could use some info on.

When I bought this boat, it had been "worked-on" by a number of "not-so-mechanically-inclined" individuals, and I've had to correct a myriad of problems and "rigged" repairs. The lower unit had been replaced on the outdrive due to damage to the previous one. I bought it with this replaced outdrive. I don't know if the trim cylinders are the right ones or not. There's where the problem is. The end caps break-off of the trim cylinders when the unit is lowered! I've replaced them once already, but when tested, BANG! Broken again!

This is something I haven't encountered before, and I'm at a loss for what could be the cause of this!

Wrong trim cylinders?
Pump wiring wrong?
Bad Karma?????

I think they refer to this as a pre-alpha outdrive - power trim serial# 5719815 also: A503179

Anyone got some input/suggestions?

HELP!!!!!
 

oldsub86

Petty Officer 1st Class
Joined
Sep 9, 2008
Messages
311
Re: Mercruiser Trim Cylinder End Caps Breaking!

Sounds like it does not have the right parts on it.
Can you find a similar outdrive and compare?

Randy
 

rbthntr64

Seaman Apprentice
Joined
Dec 2, 2008
Messages
40
Re: Mercruiser Trim Cylinder End Caps Breaking!

Your trim stop may be set wrong, allowing the cylinders to bottom out and blow the backs off.
 
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