Home   |  Message Board   |  Information   |  Classifieds   |  Features   |  Video  |  Boat Reviews  |  Boat DIY
Mercury 225 Opti tilt slowly drops - Walleye Message Central
Walleye Message Central

Go Back   Walleye Message Central > Boats, Motors, Electronics and Trailers > Motors and Props

Reply
 
Thread Tools Display Modes
  #1  
Old 05-14-2021, 12:29 PM
Northern Bob Northern Bob is offline
Slot Fish
 
Join Date: Mar 2012
Posts: 81
Default Mercury 225 Opti tilt slowly drops

I have a 1999 225hp Merc Optimax that when tilted up while on the triailer will slowly drop. If I have the engine tilted up it will slowly drop over 3-4 hours until it is near vertical. By the time I get to the lake it is wedged into the transom saver tightly. The fluid level is fine and there are no external leaks. What does it usually take to repair this? Would hydraulic leak sealer help reduce the drop? Thanks.

Edit:
I tried a new search using different words and found quite a few threads on tilt leak down. Good info and some new supports on the market that I wasn't aware of. I didn't see anything on whether the hydraulic leak stop fluids have any impact. Has anyone tried one of them?

Last edited by Northern Bob; 05-14-2021 at 01:06 PM.
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 05-14-2021, 03:40 PM
Wallychowder Wallychowder is online now
Wallhanger
 
Join Date: Jan 2021
Posts: 916
Default

Quote:
Originally Posted by Northern Bob View Post
I have a 1999 225hp Merc Optimax that when tilted up while on the triailer will slowly drop. If I have the engine tilted up it will slowly drop over 3-4 hours until it is near vertical. By the time I get to the lake it is wedged into the transom saver tightly. The fluid level is fine and there are no external leaks. What does it usually take to repair this? Would hydraulic leak sealer help reduce the drop? Thanks.

Edit:
I tried a new search using different words and found quite a few threads on tilt leak down. Good info and some new supports on the market that I wasn't aware of. I didn't see anything on whether the hydraulic leak stop fluids have any impact. Has anyone tried one of them?
Do you use a transom saver ?
Reply With Quote
  #3  
Old 05-14-2021, 04:12 PM
TomP.'s Avatar
TomP. TomP. is online now
Wallhanger
 
Join Date: Mar 2007
Location: .
Posts: 2,682
Default

It is either seals are going bad or one of the valves are leaking best is rebuild it I would imagine it is leaking under pressure while you are running if it is leaking while just sitting there.
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old 05-15-2021, 02:27 AM
Northern Bob Northern Bob is offline
Slot Fish
 
Join Date: Mar 2012
Posts: 81
Default

Yes, I use a transom saver. I tilt the engine up and down a few times when I stop if I'm driving long distances.

I checked the fluid and the level is fine with no sign of water in the fluid. I don''t notice it while on the water.
Reply With Quote
  #5  
Old 05-15-2021, 08:11 AM
REW REW is online now
Charter Member
 
Join Date: Nov 1999
Location: .
Posts: 38,662
Default

When you have an engine tilt change while not activating the trim motors - you have a leak.

Repair the leak - internal, or external and you will not have any more issues.

The typical problem is a leaking internal seal, but it may also be a leaking internal valve neither of which will show any signs of oil leaking on the outside of the trim/tilt cylinders.

If you have twin cylinders, you need to identify the leaking cylinder and rebuild it, or if you have a pair of seals and aren't sure, rebuild them both.

Best wishes.

Links below:

https://www.youtube.com/watch?v=_eQRVxqXzZU

https://www.youtube.com/watch?v=5fefUUx3Xa0

https://www.youtube.com/watch?v=D95b7dEXjYQ
Reply With Quote
  #6  
Old 05-15-2021, 12:21 PM
staylor staylor is offline
Wallhanger
 
Join Date: Jun 2004
Location: North Tonawanda, NY, USA.
Posts: 2,507
Default

If you're lucky it may just be that the trim bypass screw needs to be tightened, This is located on the starboard side clamp bracket- and is usually white plastic. If the boat was stored by the dealer they often open the bypass valve after disconnecting the battery to trim the motor "in" so they can pack the boats in a little bit tighter. On Opti's the valve is a white plastic slotted or hex screw around 1/2 inch diameter found thru an access hole in the starboard motor clamp bracket. Block the motor at the cav plate to prevent it comng down quickly, open the valve one turn and then close it fairly tight- but not so tight you shear the plastic screw- Merc gives no torque spec for this other than to say"Tighten firmly".
Doug
Reply With Quote
  #7  
Old 05-15-2021, 08:43 PM
Northern Bob Northern Bob is offline
Slot Fish
 
Join Date: Mar 2012
Posts: 81
Default

Thanks Staylor. I'll give that a try. Hopefully its that easy a fix.
Reply With Quote
  #8  
Old 05-19-2021, 10:40 AM
Northern Bob Northern Bob is offline
Slot Fish
 
Join Date: Mar 2012
Posts: 81
Default

That was so simple I'm embarrassed I didn't figure it out myself. I got about 1/4 turn when I tightened the bypass screw. It's been a day and a half and no drop in the engine. As I posted above it would have been horizontal in about 4 hours before. Heck of a lot better than the rebuild prices I was thinking of. Thanks all for the comments and Staylor, good call.
Reply With Quote
  #9  
Old 05-19-2021, 10:51 AM
Big Sandy Big Sandy is offline
Minnow
 
Join Date: Jun 2017
Location: Minnetonka, MN
Posts: 65
Default

I used to work at the place that made the tilt and trim units for Mrec.
Reply With Quote
  #10  
Old 05-19-2021, 12:21 PM
staylor staylor is offline
Wallhanger
 
Join Date: Jun 2004
Location: North Tonawanda, NY, USA.
Posts: 2,507
Default

Quote:
Originally Posted by Northern Bob View Post
That was so simple I'm embarrassed I didn't figure it out myself. I got about 1/4 turn when I tightened the bypass screw. It's been a day and a half and no drop in the engine. As I posted above it would have been horizontal in about 4 hours before. Heck of a lot better than the rebuild prices I was thinking of. Thanks all for the comments and Staylor, good call.
Guess you were indeed lucky! I've run into this with other Merc owners who have a dealer who opens the screw for storage and doesn't tighten it enough- its the darned plastic screw that seems to be a bit of a tight fit- and with no torque spec from Merc you never know how much you can/should tighten it without breaking the screw.
Doug
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 08:45 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.