Trim hydraulics blown out

[DDSBYDAY]

  Dew,  My hydraulics blew out this winter on my trim unit.  The guy at the Marina told me what happened.  Apparently it happens a lot and they had the part in stock.  Do I need to rebuild the trim motor?  It sounded like the common failure was in the tube.  The gasket and beads came with the kit but the guy at the marina kind of gave me the impression the problem was in the sleeve.  Is it a deal where as long as you already have it apart you might as well  redo all of it?  Or is it a catastrophic  you must start all over type of deal.

[dew2]

First of all what system OMC or merc? what motor,Then model # Of motor and then model # of T$T unit .
 Normally the o-rings give out in the Hydrolic rams that raise and lower the motor.The pump supplies the fluid under pressure  (UP)or a reliefe valve to lesson pressure(down) to make the rams work depending on where the switch position is.The rams will show leakage if fauilty.The pump if faulity wont work the rams especially raising the motor.No need to rebuild the rams if the motor wont pump the fluid. What did the guy at the marina tell you that happened? and what part did he say is on hand? to make the repair?
 Mercurys aren't my forte,to many special tools but the working mechanism is similar.Just thought I'd say my Merc experience.I do own 2 a 7.5 and 50 tiller

[DDSBYDAY]

  It's a 125 merc.  The part is a trim cylinder kit.  (single ram power trim thermal protection kit)   His description was that something inside the tube freezes and breaks.  There is a manual release that he said should be opened in the winter so this does't happen again.  I have had this boat for many years and never heard about that little nuggit of wisdom. 

[DDSBYDAY]

  He also said that once I get the part off I will need a special tool to remove the cap so I need to bring it to him at that point.  He figured he could do that part in about 10-15 minutes for me.  The part was over 300$ so I am proceeding cautiously. 

[dew2]

  He also said that once I get the part off I will need a special tool to remove the cap so I need to bring it to him at that point.  He figured he could do that part in about 10-15 minutes for me.  The part was over 300$ so I am proceeding cautiously. 

Without a serial number I have no idea what part you may need.I can say at a merc dealer or parts supplier you will pay a premium price.Heres a site I buy all my parts from,Well this one and Boats.net they are slow on shippig so I now use this one and you'll see your savings if you compare costs.
http://www.marineengine.com/parts/mercury-outboard/index.php