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1989 Johnson GT150 - Power Trim & Tilt

JACK LOWE

Member
I'm new here and could use some help. What should I inspect first when I 'trim out' (not under power) my motor and it make an intermittent scratchy/squeaky sound instead of the normal constant sound of the cylinder trimming my motor out. It's like it lost power to raise the motor. It'll "catch" and then continue to raise motor and that scratchy/squeaky sound goes away. It will trim all the way down like normal. Try to trim it out again and it's like it doesn't have the power to raise the motor. Pardon my lack of wording this issue correctly. I've looked at my manual and it's over my head of understanding what to look for. I don't have a good mechanic background or even a decent understanding of hydraulics, I'll get there with some help and study.Thanks in advance for any help.

Jack Lowe
 
Yep, the first thing to do is as Boobies statement... making sure that the reservoir is full when the tilt is completely in the up position.

Adding to that "Scratchy, Squeaky" sound and the "Loss of Power"... that could very well be a build up of salt corrosion build up in the top nylon bushing of the "Center Lift Cylinder" or the nylon bushings of the engine's main "Pivot/Steering Tube". The salt buildup at those two areas can get so bad that the unit items become one piece, locked tightly, unable to swivel.
 
Thanks Boobie, guess I'll need to find out where exactly one adds fluid. When you say "do it about 10 time"...what does that mean? Raise the motor, add fluid, lower motor all the way down (with/without putting bolt back in to fluid refill spot ?) and then 'repeat'...until I get a 'normal sounding' trim/tilt sound? Is there any need to drain all the fluid out? Sorry for my lack of using the right lingo. Thanks for taking the time to help me out!
 
Thanks joereeves. This 'salt corrosion' buildup you mentioned, my boat has never been in saltwater so would this possibly be just a 'corrosion' issue, if it's that, due to age of the motor. I've had this boat since 1997 and the Trim/Tilt assembly hasn't ever been in need of being looked at for problems. It is 23 years old now and understandable that parts/pieces do wear out. Thank for the time to help me out!
 
Fluid reservoir "fill/level" is the large regular slotted screw/seal assy approximately half way up the reservoir which is atop the starboard (right) side of the PTT unit. Fill to overflowing.

Always replace that screw before lowering the engine as otherwise, the fluid will be forced out... really makes a mess! And yes, it's a repeat performance in filling that reservoir should any air be trapped in there.

If after lowering and raising the engine a few times... and in removing that fill screw, you find the fluid level to still be full to overflowing... that's about as full as you're going to get it.

My explanation of the squeaking has proven (to me) to be the average cause (Nylon Bushings) but it has always been related to "Salt Corrosion". I've never encountered a bushing problem via fresh water... possible I suppose.

The noise could also be a failing internal piston of the center lifting cylinder, or a dry bushing area of the electrical motor. Have a helper work with you in trying to define just where that noise is coming from.
 
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Oxygen JOINS with aluminum to form ALUMINUM OXIDE.----That is the white powder that you might see.----So with oxygen joining up there is more material in the holes than before.------That is one reason bushings will jam tight.-----More of a problem in salt water than fresh water.----If noise persists after topping up the fluid you might investigate.
 
Oxygen JOINS with aluminum to form ALUMINUM OXIDE.----That is the white powder that you might see.----So with oxygen joining up there is more material in the holes than before.------That is one reason bushings will jam tight.-----More of a problem in salt water than fresh water.----If noise persists after topping up the fluid you might investigate.

Good one racer... never gave that one a thought.
 
Good morning, what's a good preventative measure one could take to reduce buildup of Aluminum Oxide on surfaces where they would build up? Regular cleaning/washing comes to mind. If there is an excessive buildup, what product (home brew or 'official cleaner') might you recommend. I should be getting my OMC Trim & Till PWS fluid today and will give this a try. A little reading and re-reading and all of y'alls help is working. My 'boat guy' is in FLA, i'm in TN, for the Winter, so I'm going to do what I can to resolve small issues. Thank you for taking to time to share, much appreciated!
 
Aluminum oxide has to be scraped out.-----A sealer can be used to keep air and water out of the areas where the build up occurs.-----That is if in fact jammed bushings are the problem.
 
Thanks, gotcha...seems that once it's there, it's too late. It doesn't appear that I've let those areas on my motor reach that point, just curious what might work, outside of a good regular cleaning.
 
Thanks, gotcha...seems that once it's there, it's too late. It doesn't appear that I've let those areas on my motor reach that point, just curious what might work, outside of a good regular cleaning.

Anti Corrosive Grease as a preventative would be my choice. In my 30+ years with OMC, I've found engine after engine whereas those grease fittings were neglected terribly.

Your boat guy is in Florida huh?... My home for the past 43+ years (Tampa Bay Area), almost used to it now!
 
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Hello, how's my mentors doing today. Between you 2 guys, we could solve about any problem out there.....then add Boobie and it's GOTTA work.
Here's what my brother, Steve, in Miami recommends. He has been boating for 50 plus years too, and a decent mechanic and tradesman. Retired trial lawyer with a solid grasp on the "real world". These are great products to cover what you guys are talking about.

https://nationalsupplydirect.com/white-ptef-lubricant.html
 

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Put a dab of grease on the thrust pads on midsection. It where trim rods contact midsection. When dry they creak,pop as pads get a groove in them and cause trim rods to bind.
 
Yes sir, he and his wife take their 5th wheel to a Clewiston for the Winter months and fish Okeechobee. Super nice guy and knows his stuff. Only one to ever work on my boat (20+ years now) and I'm very hesitant to let anyone else work on the motor. I noticed your remark about "grease fittings" and being neglected. Many of mine look terrible and before I reinvent the wheel. Would you be able to tell me what size 'zerks' are on my motor (yes, I admit that I just learned what those are called today). I've You Tube'd a few good videos about all this today and while I'm reading my service manual, I haven't found (yet) anything about these zerks. Appreciate your (and everyones) help... I'm learning :)
 
Think they are a 6mm x 1. Did you know spark plug threads are metric? They are NOT 9/16" x 20 as many people think......maybe they just don't care? Just a little tidbit of information for you.
 
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Think they are a 6mm x 1. Did you know spark plug threads are metric? They are NOT 9/16" x 20 as many people think......maybe they just don't care? Just a little tidbit of information for you.

Thanks timguy, appreciate you sharing... I didn't know about spark plug threads either... Reckon I'll remove a zerk, which is a funny name, and take it to a local auto place and see if they have 'em, hopefully they will. I got my trim/tilt fluid and with everyone's help who has shared with me on what to check and grease, I should be good to go, again, I hope.
 
Just wanted to thank everyone for y'alls advice, points, tips, etc. The reservoir was WAY low...filled it up with the raising/lowering many times until it was full as it would go. Found all the 'zerks' and added some Lucas Oil Marine Grease, there was one which I couldn't get to (hmm, wish I had a pic now that I'm posting this) as the the zerk was too close to (argh...) to a part of the bracket. Looking from the back of the engine, there are two grease fittings which appear to grease how the motor swivels from left to right (my bad for not describing this right...). The zerk on the left is too close for the grease gun fitting to seat, the one on the right I got grease up fine. I cleaned all the zerks really well and put these little rubber zerk boots over them. Question should (I didn't do this...) just keep cranking grease into these dudes until I see grease coming out somewhere? Again, thanks for taking the time to help a brother out!

Jack
 
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