Tricky Trim Pump Fail.

TikiHut2TikiHut2 Member Posts: 1,431 ✭✭✭✭✭
While wrapping up the stern drive oil change in the shop and doing a general once-over in the engine compartment I went to lower the OD and noticed an odd high pitched squeal when the trim pump engaged and runs. The drive tilted up fine but now the drive won't lower even though the solenoid clicks and the pump is running (but with a slight squeal). Plenty of oil in the reservoir, it just won't retract the rams.

Any input welcome. Thanks Mike
2004 FV270, 300hp 5.7 350mag MPI Merc 305hrs, 2:20 Bravo3 OD w.22p props, 12v Lenco tabs, Kohler 5kw genset, A/C, etc.etc...
Regular weekender, Trailer stored indoors, M/V TikiHut, Sarasota, Fl

Comments

  • TikiHut2TikiHut2 Member Posts: 1,431 ✭✭✭✭✭
    Maybe a trim switch failure?? I'll hopefully look further into it tonight and post an update.

    (Sterndrive.com LINK)
    2004 FV270, 300hp 5.7 350mag MPI Merc 305hrs, 2:20 Bravo3 OD w.22p props, 12v Lenco tabs, Kohler 5kw genset, A/C, etc.etc...
    Regular weekender, Trailer stored indoors, M/V TikiHut, Sarasota, Fl
  • 212rowboat212rowboat Member Posts: 2,591 ✭✭✭✭✭
    was/is there any damage to the stanchions?
  • TikiHut2TikiHut2 Member Posts: 1,431 ✭✭✭✭✭
    Stantions as in OD Rams? No, but they haven't been in the water since memorial weekend so they may be stiff or crusty and ill tempered due to lack of use, like their captain. ;) I'm hoping they're just funky from sitting for 8wks and I'll get out there tonight and with a little lube they'll behave. I'll see if i can get a video posted to my youtube acct so you'll get a better feel for my trim pump sound.

    The last linked theory about trim senders possibly being screwed up sorta sounded familiar because the trailer switch on the throttle lifted the drive but the same trim switch function only causes a pump sound but no retraction action. Thanks, Mike
    2004 FV270, 300hp 5.7 350mag MPI Merc 305hrs, 2:20 Bravo3 OD w.22p props, 12v Lenco tabs, Kohler 5kw genset, A/C, etc.etc...
    Regular weekender, Trailer stored indoors, M/V TikiHut, Sarasota, Fl
  • TikiHut2TikiHut2 Member Posts: 1,431 ✭✭✭✭✭
    edited July 2013

    The evening update and youtube video to watch (TRIM PUMP VID LINK) .

    Tore out the pump and the pump seemed fine to me except for the slight squeal on the down command and a a sputtering amount of oil that was coming from the down port with both hoses disconnected. It may have been simply sucking air from the up port but thats all I have to go on. It has plenty of fresh clean oil and the lower screens in the pump looked brand new with no debris or water.

    Could it be a bad ram or a some sort of other issue besides a bad trim pump? I'd hate to sink some serious money into a new pump only to realize it's a problem in a line, a ram, or something that someone later said oh yeah it was that other thing. With twenty something views I'm hoping somebody has an epiphany. On the other hand maybe it's just a bad pump.

    Thanks for any insight. Mike


    2004 FV270, 300hp 5.7 350mag MPI Merc 305hrs, 2:20 Bravo3 OD w.22p props, 12v Lenco tabs, Kohler 5kw genset, A/C, etc.etc...
    Regular weekender, Trailer stored indoors, M/V TikiHut, Sarasota, Fl
  • 212rowboat212rowboat Member Posts: 2,591 ✭✭✭✭✭
    Man, that oil sure looks thin in the video..

    The stanchions get grabby sometimes, and drag crap past the seals is why I commented that.. I've no experience in trim hydraulics, but have seen it in other applications.. when it does that, even if the debris only hang for a little bit under the seal, crap can get in, or oil can get out.. going down needs good volume, going up needs good pump, right? I'm thinking going down is when you would discover a good sized leak.. I could be wrong, though.
  • TikiHut2TikiHut2 Member Posts: 1,431 ✭✭✭✭✭
    edited July 2013
    Thanks Drew. The oil viscosity was dead on what the specs call for, seemed pretty clean for its age and it wasnt leaking oil anywhere. The sump screens were completely clean and the rams pumped up as normal. Down just doesnt happen even though the pump is running.

    Im missing something but not sure what the trick is. Hope I dont have to resort to guessing with new parts.
    Thanks again. Mike
    2004 FV270, 300hp 5.7 350mag MPI Merc 305hrs, 2:20 Bravo3 OD w.22p props, 12v Lenco tabs, Kohler 5kw genset, A/C, etc.etc...
    Regular weekender, Trailer stored indoors, M/V TikiHut, Sarasota, Fl
  • aero3113aero3113 Member Posts: 8,776 ✭✭✭✭✭
    I had a boat once with the same issue. I had luck with someone working the switch while I was giving the drive a firm push down. I think the rams can bind if the seals get dry and they just need some help to free up.
    2008 330EC
  • TikiHut2TikiHut2 Member Posts: 1,431 ✭✭✭✭✭
    edited July 2013

    I'll put it all back together tonight and give that a try. It certainly sounds reasonable and less painful than a new pump.

    Anybody know if there's a particular process needed to purge any air out of the system during re-assembly? Thanks. Mike

    EDIT: found a forum comment that confirms Aeros input so I thought I'd add it here for the next schlep like me looking for answers to the same problem someday:  (LINK)  How to bleed the air from your trim motor/rams. I'll follow up with the solution if this isn't it. 
    Post edited by TikiHut2 on
    2004 FV270, 300hp 5.7 350mag MPI Merc 305hrs, 2:20 Bravo3 OD w.22p props, 12v Lenco tabs, Kohler 5kw genset, A/C, etc.etc...
    Regular weekender, Trailer stored indoors, M/V TikiHut, Sarasota, Fl
  • V8192V8192 Member Posts: 18 ✭✭

    Sounds like a stuck check valve, the pump (old ones anyway) run the same direction and you

    are just changing the flow direction to the rams sounds like the valve is stuck on the down circuit

    not allowing flow which is why the pump squeals as it is making pressure but is not flowing.

    I don't know if you can remove or service the check valves. My experience is with my old

    Merc pump on my outboard. Someone else may know if there is a manual release valve on the pump that will let you move the lower unit up and down by hand. I've not been that involved with

    my new ride to know about the newer pumps. 

  • TikiHut2TikiHut2 Member Posts: 1,431 ✭✭✭✭✭
    Well, here's the final wrap. The trim pump was apparently overdue for some TLC like a nice fresh oil change(no water but quite nasty), the tank had a small crack so it also got a through cleaning and repair. After pricing the whole assy I was very glad that it wasn't a pump problem causing the OD trim issue.

    Looks like Aero and others had it right about it being sticky on the up side. After refreshing the whole pump and lubing everything(including the ram seal and joints) overnight I recruited some help to push down on the drive while I operated the switch and it now operates up/down just fine.

    Even though I opened the system I didn't need to bleed the air out either. Seems that unless a ram is rebuilt, these trim pumps will self prime pretty well. Also, I had replaced a "down" relay 6mths ago and the "up" one seems temperamental so my advice would be to replace them both if one gets glitchy.

    Hope the details help someone else down the line. Now it's on to the next item on my off-season punch list. Thanks again for the trim pump input. Mike
    2004 FV270, 300hp 5.7 350mag MPI Merc 305hrs, 2:20 Bravo3 OD w.22p props, 12v Lenco tabs, Kohler 5kw genset, A/C, etc.etc...
    Regular weekender, Trailer stored indoors, M/V TikiHut, Sarasota, Fl
  • aero3113aero3113 Member Posts: 8,776 ✭✭✭✭✭
    Glad you got it working!
    2008 330EC
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