Power trim problems

kevmacmills

New Member
Jun 15, 2010
12
Bellingham, WA
Boat Info
268 Sundancer 1989
Engines
7.4l Mercruiser, Bravo One
Greetings, all:

I have a 1989 268 Sundancer (7.4l merc w/ Bravo outdrive) that is having trouble with the power trim system. When I got it out of storage, I raised the outdrive and heard a loud groan about half way up. The outdrive shuttered some, but it did return to the fully upright position. I checked things out and noticed the fluid level in my Oildyne trim pump was a bit low, so I filled it up with ATF.

I used the boat this last weekend and had the same thing happen. I checked the fluid level again and found it to be low - lower than before! I filled it again and with the boat in the driveway, I lowered and raised the outdrive a few more times and could see very frothy ATF returning to the reservoir. Checking out the connections to the pistons, I noticed pretty fresh looking ATF dripping from my drain hole.

Obviously I have a leak... right? Is that what is causing the trouble lifting the outdrive? Is air being drawn into the system? I see no indication of a leak on the outside, so how the heck does one get to the hydraulic hoses on the inside??

Thanks much!
 
I don't know if this is your problem (or has worsened your problem), but Merc recommends 30wt oil (or their trim fluid). Was it different in 1989? I don't know - but mine is a '99 and that is what is recommended. Again, would ATF cause this problem... I'm not sure what it would do.

If it's struggling to move, my first thought would be the cylinder spacers/sliders inside the cylinders. Maybe one of them has broken.

These are just some random thoughts that might or might not help. I'm sure someone with more knowledge on this subject will be able to help more.
 
Hi, Dennis - thanks for your reply.

I went with ATF because my Clymer shop manual said "Quicksilver power steering fluid or Dexron II ATF". Later, after I'd filled it with ATF, I found my Mercruiser maintenance guide and it said I should be using Quicksilver trim fluid or motor oil. Not sure why the discrepancy, but it seems like it wouldn't be overly crucial since this is a low pressure system...?

Thanks...
 
Well, I made a very interesting discovery yesterday that I'll add to the mix: My power trim reservoir is cracked! After some searching, I've found this is a common occurrence with the older 1-bolt design. From what I've read, Mercruiser abandoned the 1-bolt design (18525A1) and went with a 4-bolt design. In order to use this new design with my old pump I need to purchase an upgrade kit (883169A1) that runs anywhere from $200 on eBay to $400+ at various online dealers.

I also see that I can purchase, for around $40, an after-market replacement (ARC-M525) for the no-longer-made 1-bolt design. Is that worth it or will I have this same problem again in a few years?

Now for the real question: Was this the sole cause of the trim having trouble? Air in the system will certainly mess things up, but did anything get damaged? I may be over analyzing now, but it sounds to me like the pump is making "funny" noises. A kind of crackling at times instead of the normal steady pump sound.

Thanks for any input...
 
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I would get the $40 replacement. I very much doubt you'll have a repeat performance anytime soon. There's many 1-bolt versions still out there doing just fine. Is yours the original? Can't really fault something for lasting 20 years, you know? Besides, a brand new motor/pump/reservoir - the whole thing - is about $500.

While there's no way to say with any certainty, I would lean towards thinking that once you put the new tank on there and flush the system out real good and put new oil in there, you'll be just fine.
 
I managed to find the Sierra equivalent (18-6771) locally for $53. Shocking price for a plastic bowl, O ring and a bolt, but it is still less than the upgrade kit. This reservoir has some reinforcing plastic structure on the inside, so maybe it will last longer?

I'm wondering about flushing the system? What is involved in purging the old fluid? I assume I'm going to detach the hydraulic hoses at the pistons and run the motor?

Thanks.
 
If you are losing trim fluid and the pump reservoir is not leaking, then my guess is that the hydraulic hoses between the pump and the manifold on the sterndrive are leaking. The manifold is located outside the boat on the bottom of the drive, sandwiched between the Mercathode and the drive. Let me know if you need more info...
 
I managed to find the Sierra equivalent (18-6771) locally for $53. Shocking price for a plastic bowl, O ring and a bolt, but it is still less than the upgrade kit. This reservoir has some reinforcing plastic structure on the inside, so maybe it will last longer?

I'm wondering about flushing the system? What is involved in purging the old fluid? I assume I'm going to detach the hydraulic hoses at the pistons and run the motor?

Thanks.

I had to replace the tank on my previous boat. P.O. had tried to repair the crack and nothing holds. You likely have air in the system which is why you had the frothy return. Can you disconnect the return line and catch everything coming from that? Fill tank with fresh fluid as the return empties the tank
 
My 89' sea ray w/4.3l likes to stall when you press the trim button at idle or if you are cruising the rpm will drop when you press the trim. It sounds like a bad connection but im not sure, anyone run into this problem?
 

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