Dodgey power trim, or is it.

[SeaHunt]

Hi Guys,
I was coming back from Tangas across the bay Saturday arvo and pushing it along. It was a bit bumpy on the western side and as I was entering the Creek at Nudgee beach in not much water I trimmed the motor up, but it only wanted to go up a little and then fell most of the way back down by itself.
By the time I got to the boat ramp in smooth water and checked it again it was working fine. So I guess the question is does all that thumping up and down cause an air lock or bubbles in your trim oil or something, or could I have a more serious problem. ? ???
Only about 130 hours on everything so pretty new gear.

[searaider]

Geday SeaHunt ,
It sounds like you may have a problem . :-/ No matter how much rough water work you do , it should have no effect on your trim & tilt .

Peter
Searaider 2

[Spaniard_King]

Sea hunt

could be a couple of things

low oil level in trim unit

the bypass vale (manual tilt valve) is not closed properly

or you have an internal failure (check oil level if oil aint dirty trim unit should be OK)

Check trim oil.... Trim motor all the way up next to trim ram is a reservoir should be some sort of screw/ bung, undo this and oil should drip out if it doesn't top it up with Auto transmission oil (yeah the red stuff)

Garry

[DaneCross]

SeaHunt,
I may be pointing out the obvious, (but it confused my uncle a couple of weeks back on my boat) my motor will only trim to a certain height while travelling at anything quicker than just above an idol. Once stopped/at idol you can then trim it right up as high as you like. If its trimmed right up, then you engage the gear and bring the revs up the motor will automatically drop to its 'highest travelling trim level'. Its probably something you aleady knew, but thought I'd point it out to you just incase yours is like mine.
Hope its nothing serious.

Dane

[cooky]

mate - I had (have) the same problem and the first week I took my boat out (camping up north) I hit a couple of sand banks (not badly) - I had this sickly feeling (you know the one when you feel like you;ve been had or something's going to cost lots of money :'() when I tried to get to where I had to pick some people up (shallow) and the motor kept F**king going down. We checked it out as much as we coudl, but went out anyway - it seemed to work at speed - we thought the hydralic might need repairing (leak) and that putting power on at low speed was putting too much torque and it couldn't handle it.

I read the instruction manual for the motor for the first time last weekend and what do you know. My Merc 115hp has a feature (I assume safety) that above 2000rpm the power trim will return to normal operating trim. I'm assuming that maybe some people have had accidents or it puts too much pressure on the transom or something, but it says it so it must be true.

This might be your problem / solution / answer

[SeaHunt]

Thanks guys , a couple of things to check there.
Cooky , reading the instructions ..., it's always the last thing us guys do , just ask the women. It is a 2003 Model Merc, only 60 HP though, but you could be on to something. I am always putting over sand bars with it trimmed right up , not sure if I would have been over 2000 revs previously, but on Saturday I probably was , I wanted to keep the speed up a bit there were a few small waves breaking , it was like a mini bar. (not the kind with grog in it). ::)

[cooky]

mine's a 2001 model Saltwater - so I'd say that's it. Funny though how many times I wanted the bloody thing trimmed up and needed more than 2000rpm - strong tides and travelling too slow for too long. Was really annoying me. We camped for a week at Taylors Beach near Lucinda (NQ) and the channel to get to open water is a few kms long at any sort of lowish tide - it took us an hour one one occassion to get out. I came in at night following my GPS at 0.3 (closest zoom) and still bumped a sand bank or twenty (particularly on one occassion as I was aiming at the wrong channel marker light and hit a large sand bank at speed at about 4am in the morning. Coming back through the channel in the day following my GPS we wanted to go a bit faster, but I still wanted the motor trimmed up in case (that's when it got a bit frustrating). Really interesting when the bottom of your boat hits a small sandbank - you can see clear water - your boat is stationary and you trim the motor up - you need to give it some to slide over the sandbank and the bloody motor keeps trimming down to chew sand ;D

Driving on the trailer it does similar at times (trim motor up - give it some to crawl up the last bit and motor trims down to bump the ramp)

[dnej]

Great info guys, must be a pain in the but.
It was mentioned about auto transmission fluid, my manual, for an a 1980 Mariner, shows SAE 30 oil.
Did trim systems change over time, to use transmission oil.?
Would be great to know
Regards David