Author Topic: Trim Problems (Read 14448 times)

Shrom CVX-18 · « **on:** May 26, 2012, 01:10:04 PM »

Ok, I put the outdrive back on my boat and ran the trim..Runs up fine but when run down it runs extremely slow. and when you let off the down switch and look at the outdrive it even raises back up slightly The motor seems to be running like it should nice and strong. but the down trim does not go as fast as is should be( like when I run it up.)

I need help

cant figure it out. almost like a check valve is not working?

Jason · « **Reply #1 on:** May 26, 2012, 02:05:59 PM »

Sure you got all the hoses connected correctly? It worked fine before you removed the outdrive? You may gotten some debris in there. you could try disconnecting the lines and drain the fluid, blow the lines out.

Shrom CVX-18 · « **Reply #2 on:** May 26, 2012, 03:29:03 PM »

It worked fine last season, (last time used) then before I put the boat away for the winter I pulled the outdrive off. I didn't disconnect anything. That's why Im kinda stumped as to why its giving me troubles.

Shrom CVX-18 · « **Reply #3 on:** May 26, 2012, 04:03:04 PM »

OK, so I pulled the steel braided lines off down at the cylinders and pressed the up and down button, Fluid came out just as they should and were they should. So the lines down to the cylinders seem to be clear.

Jason · « **Reply #4 on:** May 26, 2012, 04:57:42 PM »

Nothing is binding up in the gimble or something? You could unbolt the cylinders at the drive and manually lift it up and down and see if there is something else going on.

Rich_V174SS · « **Reply #5 on:** May 26, 2012, 05:41:01 PM »

I've seen the cylinders bind up a few times in the end caps where the piston comes out. I've also heard of sticking check valves in the pump preventing the drive from going back down. If you leave the trim rams disconnected from the drive and run them up and down see if one of them gets hung up while the other does all the moving.

Shrom CVX-18 · « **Reply #6 on:** May 26, 2012, 08:43:09 PM »

Thanks guys, I'll check it out more in the morning.

Shrom CVX-18 · « **Reply #7 on:** May 27, 2012, 09:58:33 AM »

Disconnected the outdrive from the rams. and ran the pump...same problem. both rams still wont go down. I pulled the pump out of the boat and took off the junction box on the bottom and found a check valve, pulled that apart and made sure it was clean. put it all back together and nothing is different.

Bayflite73 · « **Reply #8 on:** May 27, 2012, 10:57:38 AM »

Maybe it's a stupid question, but could it be the rams themselves? Maybe freeze thaw took there toll?

Shrom CVX-18 · « **Reply #9 on:** May 27, 2012, 11:32:10 AM »

Quote from: Bayflite73 on May 27, 2012, 10:57:38 AM

Maybe it's a stupid question, but could it be the rams themselves? Maybe freeze thaw took there toll?

I was kinda thinking the same thing myself, but When I pull the line off and the outdrive is up it falls as it should. Which to me says that they are still functional.. but I could be wrong. I would think if they were bad they would stick.

not sure if my thoughts are correct on that.

Rich_V174SS · « **Reply #10 on:** May 27, 2012, 01:27:17 PM »

Like I said, they could be frozen up where the pistons come out of the end caps on the rams.

Shrom CVX-18 · « **Reply #11 on:** May 27, 2012, 01:59:36 PM »

Rich is there a way to fix that? is it safe to unscrew the end caps?

Rich_V174SS · « **Reply #12 on:** May 27, 2012, 02:06:42 PM »

You can try spraying in some penetrating oil like PB Blaster or similar and working it in by cycling the rams back and forth to see if they loosen up. You can try removing the end caps but to remove them from the pistons you have to completely disassemble the pistons. Whenever we had this happen at the shop we would just replace the pistons with new ones from SEI, they were around $120 plus shipping costs. Saved time and money from dinking around with them for hours trying to fix the problem.

SEI Link:
http://www.sterndrive.cc/mm5/merchant.mvc?Screen=CTGY&Category_Code=MercruiserTrimCylinders

Rich_V174SS · « **Reply #13 on:** May 27, 2012, 02:16:27 PM »

Another thing to note is if water got into the ram bushing/end cap causing corrosion and binding then it can also get into the trim oil and pump so it's a good idea to either rebuild the cylinder or replace it.

Shrom CVX-18 · « **Reply #14 on:** May 27, 2012, 03:32:54 PM »

Quote from: Rich_V174SS on May 27, 2012, 02:16:27 PM

Another thing to note is if water got into the ram bushing/end cap causing corrosion and binding then it can also get into the trim oil and pump so it's a good idea to either rebuild the cylinder or replace it.

My guess is it is probably the rams like you are saying, but what i'm confused why... if they are binding up how come it is only when having fluid running through them. If I drain the fluid and leave a line unhooked. I can move them in and out buy lifting the outdrive up and down buy hand.

Rich_V174SS · « **Reply #15 on:** May 27, 2012, 05:41:01 PM »

Then the problem is not in the cylinders if you can move them in/out with no fluid. The problem is either with the reverse shut-off valve or a check valve inside the pump.

wexrocks · « **Reply #16 on:** May 27, 2012, 11:00:19 PM »

Any idea which valve creates/relieves pressure on down trim? Seems like that's the gremlin in the system... as I was explaining to Shrom earlier, I've had trim systems/pumps completely apart, and they seem complicated for the sake of complication, maybe it's just me. I would think a shutoff valve and a bidirectional motor would do it, but my hydraulic knowledge is limited.

Shrom CVX-18 · « **Reply #17 on:** May 28, 2012, 06:40:18 PM »

I think i'm going to try by-passing the reverse lock and see if that does anything. That way I can at least possibly roll that out as being bad. If the trim runs like it should doing that, then I know that is the problem. and will purchase a new one.
If it is not that it kinda leaves only the pump as being bad some where inside at a check valve.

I'll do that this week at some point.

dorelse · « **Reply #18 on:** May 28, 2012, 07:21:59 PM »

If it makes you feel any better Shrom...my reverse lock-out thing is still leaking after rebuilding it.

I think for me, its time to just upgrade to the newer style pump and be done with it.

Shrom CVX-18 · « **Reply #19 on:** May 30, 2012, 05:33:42 PM »

Well I pulled the check valves out of the reverse lock, and hooked everything up that way to see if it would travel down like it should...Same thing

At this point I do not know what to think. Not too much more to check out. its either the pump or the rams. I don't really want too, but I'm thinking of buying a new pump..