Trim not working - is this a bad idea?

AlabamaNewbie

Petty Officer 1st Class
Joined
Jun 25, 2018
Messages
239
1986 Glasstream 172 Cutlass with 3.0L Mercruiser /Alpha One.

Restoring the boat, and trying to work through all the electric/mechanical parts before ripping the thing apart, just so we will know what's what. We are having day after day of pop up thunderstorms, and they always seem to pop up when I get off work, so I am unable to really get anything done on this thing. So I sit here thinking about the plan. I am definitely a planner. I also understand that you make a plan, you try and stick to the plan, you watch the plan go sideways, then you throw away the plan. But I at least have to have one. :D So I am thinking about what to do and in what order when I do get a clear day, so I can attempt to efficiently use my time. Most of this I could probably figure out if I was in front of it, but I'd rather ask stupid questions and form my plan.

Anyhoo - I have read a gazillion posts about tilt/trim systems but you know - *my* question is different that those, so I am asking it again. :cool:

I can hear the solenoid click and the motor whir, but she doesn't go up and down. The fluid is at the full mark and does not appear to have water in it. I have done the "raise/lower" of the drive by hand about 4 million times to try and bleed it, with no change. So my belief is that the motor is shot. Even though I can hear it whirring, its not moving fluid. There is no fluid leaking anywhere either.

Now the hopeful side of me is saying "well maybe it just got some sludge or debris in the lines and its clogged". So my next troubleshooting task I want to do is to completely removed the fluid, clean the lines, put in new fluid, bleed, and see where we are. I know you are thinking "why not just replace the motor while you are at it?" Well, this is a joint project between me and my son on a boat we got for next to nothing, and we have a dollar figure of where we will say "no more". Every dime spent on something that is "ok" is money not available for other things - ( like how I know the hull repair is going to be more costly than budgeted, so I am trying to save money elsewhere on things that can be replaced later as part of maintenance). Anyway- I digress.

My thought is that after I remove all of the fluid, that I blow low pressure air through the lines to attempt to dislodge anything that may be clogging it. I'd leave the fill cap off so that it doesn't build pressure and blow out seals and such. Good idea or bad idea? Also, other than a clogged line or bad pump motor, what could it be? I have some experience with hydraulic pistons and know that they are pretty tough, and if they do go bad its usually a seal and will leak. Again, I have no leaks -so I feel pretty confident the pistons are ok.

On another note - I know we can't solicit business, but is it ok to ask for recommendations? I am trying to find a good supplier of upholstery vinyl for when we get to that part. Again, looking for low cost so I can move any surplus budget from reupholstery to deck/stringer repair.

Thanks for tolerating the long post - I'm obviously and long winded.....
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,383
if your up against the stop for a long period of time, the load holding check valve in the block gets stuck. either swap the hoses (as raising is about 4 x the pressure of lowering) or have a buddy or two stand on the outdrive as you try to lower.

if that doesnt work, either spend $250 to get a new one or spend $80 with your local hydraulic repair shop to get it fixed.

the tilt pump is a parker/hydrodyne 108 series hpu.
 

wellcraft-classic210

Master Chief Petty Officer
Joined
Sep 22, 2010
Messages
839
I like Naugahyde brand for its durability and soil resistant coating -- Some lower cost vinyls are dirt magnets & best to use color that do not show it or avoid them altogether.

that said check out http://www.rochfordsupply.com and compare to on line bidding sites for a bargain on seconds
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,338
There is a plastic coupler that joins the motor to the pump, remove the motor from the base, it may even be not connected or broken.
 

TurtleTamer

Petty Officer 2nd Class
Joined
May 10, 2018
Messages
143
It could be one of your rams. Pull the lines on one side at the distribution block on the outdrive, not at the hose. Plug them with suitable plugs. Attempt to raise and lower it. If it goes up and down, the ram you isolated requires replacement or repair. If it doesn't go up and down, try the other side. A seized ram will keep the other from doing its job.
 

AlabamaNewbie

Petty Officer 1st Class
Joined
Jun 25, 2018
Messages
239
I am thinking its the pump.I confirmed again that the fluid level was full, and did the raise/lower by hand of the drive another couple of million times (or so it seemed). there was no pressure at all in either direction. I was more focused last night on running the engine, but this weekend I am going to remove the lines from the rams and see if I am even getting fluid to them. I just have this feeling the pump is shot.
 
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