Alpha 1 losing trim on plane.

[stormrider]

Last night I took the ol' Mariah out for a spin. We planed out, then raised the trim, and then I watch the trim gauge slowly go back down as the bow settled back into the water. It will hold up when idling, but will drop fairly fast when I trim it up on plane. Checked the fluid level and it's full. Is my guess of fluid bypassing in the cylinders correct? Are they rebuildable or do I just need to buy new cylinders?

 

[stormrider]

Re: Alpha 1 losing trim on plane.

C'mon fellas, I know I'm new to the forums, but can you gimme ideas where to start?

 

[natemoore]

Re: Alpha 1 losing trim on plane.

Howdy!

Have you downloaded the FREE service manuals for your drive and engine? It's available on this forum. I'm pretty sure the manual will have some testing procedures for the hydraulics?

Check here to see what rebuild kits are available: http://www.mercruiserparts.com/SelectModelType3.asp?class_id=1

or more specifically here: http://www.mercruiserparts.com/Show...nbr=210&bdesc=POWER+TRIM+CYLINDER+REPAIR+KITS

Mine work fine, fortunately, so I'm not yet an expert on that part of my boat.

 

[jtmarten]

Re: Alpha 1 losing trim on plane.

Howdy!

Have you downloaded the FREE service manuals for your drive and engine? It's available on this forum. I'm pretty sure the manual will have some testing procedures for the hydraulics?

Are the manuals back online? They were removed several weeks ago.

 

[natemoore]

Re: Alpha 1 losing trim on plane.

Are the manuals back online? They were removed several weeks ago.

Oh...bummer. Let me guess. Cease and desist order.

 

[jtmarten]

Re: Alpha 1 losing trim on plane.

I'd bet other members may be able to email the proper file(s). Some are very large though.

 

[stormrider]

Re: Alpha 1 losing trim on plane.

I have the manual, guess that's where I'm heading tonight since nobody will offer their ideas (except did you look in the manual?). Gee fellas, I see all kinds of folks asking lots of questions in here that have tons of input and replies, and nobody will share their ideas/experiences for my situation? Appreciate it guys

 

[Kaplooi]

Re: Alpha 1 losing trim on plane.

Obviously there's a problem somewhere with your hydraulic cylinders maintaining pressure. It can only be a problem in your cylinders or the trim pump. My guess is that your trim pump's valve body is failing and cannot withstand the pressure placed on the rams from the thrust of the outdrive. But it could be either or both of the cylinders too. The tests in the Manual step through all of these possible causes starting with the trim pump and then each cylinder. Is the requirement to have the test gauge what's at issue here? ($360) If so your best option is to replace your trim pump valve body and see if your problem's fixed. If not, toss a coin to determine which trim cylinder might be faulty and replace it and see if it holds pressure. If not replace the other cylinder. Overall it's probably best to just bite the bullet and buy the gauge and do the tests or find a vendor with a really good return policy on 'installed' parts. Regardless you can be guaranteed something is leaking internally and allowing fluid to flow back where it shouldn't.

 

[6meter]

Re: Alpha 1 losing trim on plane.

I have the manual, guess that's where I'm heading tonight since nobody will offer their ideas (except did you look in the manual?). Gee fellas, I see all kinds of folks asking lots of questions in here that have tons of input and replies, and nobody will share their ideas/experiences for my situation? Appreciate it guys

Did you ever think that maybe, just maybe nobody has an answer? Would you like a wrong answer? I could give you that. Or how about some patience. You are, BTW, asking for "free" advise.
Your problem is in your trim switch. Or your problem is in your trim pump. Or your problem is in your trim pistons. Or your problem is in your attitude. HTH

 

[Fishing56]

Re: Alpha 1 losing trim on plane.

Years ago I had a 1978 Mercury 90 Hp outboard. Bought it new etc. After about 10-12 years of heavy usage, my motor would slowly leak down while tilted up or under way with trim up. I was able to use a re-build kit to replace the seals and o-rings fairly easily. If I recall this was fairly easy and inexpensive.

You didn't mention how old your Mariah is. I have a 1996 Shabah that I purchased new. So it is now 14 years old and have not had any issues the power trim system. If your not loosing any oil, then it rules out your hoses. My guess would be the trim cylinders. Usually what goes wrong with the pump is a failed o-ring. With the earlier boat, there was a rebuild kit for the pump also. Caution, there are some spring and little steel balls that can jump out or stick with the oil. Take some digital pictures at each step for reference when putting back together.

Fishing56

 

[stormrider]

Re: Alpha 1 losing trim on plane.

Did you ever think that maybe, just maybe nobody has an answer? Would you like a wrong answer? I could give you that. Or how about some patience. You are, BTW, asking for "free" advise.
Your problem is in your trim switch. Or your problem is in your trim pump. Or your problem is in your trim pistons. Or your problem is in your attitude. HTH

Whoa there big fella. I was just looking for some ideas of where to start. You don't need to hammer at me bud.

BTW, it is a "free" forum. I got a "free" pass. So, why can I not ask for "free" advice just like all the other thousands of people on here?

 

[stormrider]

Re: Alpha 1 losing trim on plane.

Years ago I had a 1978 Mercury 90 Hp outboard. Bought it new etc. After about 10-12 years of heavy usage, my motor would slowly leak down while tilted up or under way with trim up. I was able to use a re-build kit to replace the seals and o-rings fairly easily. If I recall this was fairly easy and inexpensive.

You didn't mention how old your Mariah is. I have a 1996 Shabah that I purchased new. So it is now 14 years old and have not had any issues the power trim system. If your not loosing any oil, then it rules out your hoses. My guess would be the trim cylinders. Usually what goes wrong with the pump is a failed o-ring. With the earlier boat, there was a rebuild kit for the pump also. Caution, there are some spring and little steel balls that can jump out or stick with the oil. Take some digital pictures at each step for reference when putting back together.

Fishing56

Thanks! It's a 1992 MX19 that was rode hard before I bought her last year. Never has any problems with the trim until the other night. Resorvior is full of fluid, but I noticed the pump motor sounded a bit different the past few outings. A little higher pitched whine while in use. Looks like my problems may be in the pump...