Trim /Tilt Motor Replacement

[Bass-by-you]

I have an '84 mercruiser 5.0/Alpha 1. The trim and tilt motor is the old style "square" casing. The motor housing is extremely aged....I can find no labels to tell me manufacturer, model, etc. Rain water got into the dash mounted (NOT factory) switch and created a short. When I noticed this the outdrive was all the way up and the motor was still trying to spin the pump.

I shut every thing off and opened the deck hatch. A small amount of smoke came up from the motor. I pulled the motor and bench tested it for functionality. The motor still runs in both directions, sounds smooth and quiet. One thing I did notice....I could grasp the end of the motor shaft and with very little effort I could stop the motor from turning. I know that should probably stop messing around and just orer another motor. But the things are outlandishly expensive. On iboats I see them from $200.00 to $650.00. So, before I decide to scrap this motor:

1. should the torque of this motor be so low that I can stop it by grabbing the end of the shaft?
2.which manual in the DIY section do I need to download for this information
3.what is the difference between a $200.00 replacement and a $600.00 replacement?
4. any recommendations on which motor I should get (if I just have to)?

As usual guys, I really appreciate the help I get here.

 

[ErieRon]

Re: Trim /Tilt Motor Replacement

Try manual #6 section 5. It should help you ID what you have. You'll need to check your serial number in the "models covered" page in front.

I've never had any issues with mine, so I can't answer the other questions...sorry.

 

[Bass-by-you]

Re: Trim /Tilt Motor Replacement

Thanks ErieRon...Yeah the manual shows how to test the motor, which I had already done, but it does not give any specs on torque or other performance parameters. Just does it run in both directions. Any body else?

 

[ErieRon]

Re: Trim /Tilt Motor Replacement

Bass-By-You;

Does the motor just turn a directional valve, or does it rotate something to create the pressure? There is a pressure test procedure in that manual that should tell you if yours is working properly. Unfortunately, you need a hydraulic gauge capable of 2600 psi.

Also; here's a link to a site with all of the pieces parts you might need to rebuild that thing. http://www.psepmarineparts.biz/store/mercruiser_power_trim_pumps_and_components.htm

If you haven't yet, you'll need to identify the exact one you have by model/part number.

Hope this helps some.

 

[Bass-by-you]

Re: Trim /Tilt Motor Replacement

ErieRon..thanky...that site got me a lot closer.....unfortunately, the motor casing is so weathered and beaten after 29 years of service there are just no identifying labels of any kind visible on this thing. And, I'm not even sure it is bad!!!! As I stated earlier, the motor runs fine on the bench in both directions. If it were not for the fact that I can grab the end of the shaft and stop it with my hand, I would put it back in the boat................I just don't know how much torque it shoud have and the system worked fine before all this nonsense started.

Thanks for the help

 

[Bass-by-you]

Re: Trim /Tilt Motor Replacement

BTW..Erie, the motor shaft fits into a rotational pumpwhich pressurizes the hyra-lines.

 

[jtybt]

Re: Trim /Tilt Motor Replacement

Go to your local merc repair shop and get a used tilt/trim pump assembly. I bought NEW aftermarket for $100 and used merc for the same price.

 

[Bass-by-you]

Re: Trim /Tilt Motor Replacement

Great idea...I'll check on it.

Thanks to Y'all

 

[ErieRon]

Re: Trim /Tilt Motor Replacement

Glad to help. I understand your concern about the torque, just don't know the answer

There were only two or three used on that engine in that era. They're pretty easily identified by their reservoir material, shape etc. Do you have the ability to post a picture? I'm sure we can figure out what it is. Then you could shop around the parts.

Another thought is to hook up an ammeter and see what it's drawing when you stall it by hand. If I remember, it draws 115 amps @ 2600 psi. I would assume that grabbing the shaft would reasonably duplicate that if it is turning a pump/impeller under full load...just a thought

 

[Bt Doctur]

Re: Trim /Tilt Motor Replacement

If you mean the square motor housing, like this one you cant stop the motor shaft with your fingers when power up.

 

[Bass-by-you]

Re: Trim /Tilt Motor Replacement

Erie and Bt....Thankyou for the feedback.............I will post a pic soon. I can tell you this, the motor housing is the old "square can" style. The hydra-fluid container is the cylindrical aluminum ( at least not plastic). All of the research I have done has pointed me toward the exact unit Bt is showing me. Bt, if that shaft can not be held by hand then there is clearly no sense whatsoever of me putting my old unit back in the boat. And yes I should run an amp load test. Unfortunately, I am under time constraints, blah, blah, blah.

So basically if I cannot find a used unit at a dealer as suggested above, I have intended to buy the unit in the picture shown by Bt. But I would not have gotten to the decision to buy a unit at all without everybody's feedback..

Thanks guys.

 

[HT32BSX115]

Re: Trim /Tilt Motor Replacement

Howdy,

Before you buy a new motor, be sure to take a look at ebay for motors pumps etc.

I saw several complete pumps new and used there.


Regards,


Rick

 

[Bass-by-you]

Re: Trim /Tilt Motor Replacement

Thanks Rick, I'll do it.

 

[Bass-by-you]

Re: Trim /Tilt Motor Replacement

Well, after the great responses I got here, I thought I would bring you all up to date. Yesterday I took my 25 year old pump motor to the marine shop I have been dealing with. They are a Mercury/Mercruiser/Mariner house. The guy I have been working with dutifully went through his part catalogues trying to "estimate" which pump motor I had and which to buy to replace it. Eventually though he told me that unless I wanted to spend $600.00 for both a motor and pump replacement, he could not figure it out and could not help me.
I got in my car to drive home feeling like I was heading to a funeral. I decided that I would just have to stop at every boating parts house I could find and beg for them to look for a left over motor they could sell me and that one day.....some one would have the right motor.

Three blocks down the road I came across a Johnson/Evinrude house. I was certain there was no way they would have anything I needed, but desperate people have desperate ways, so I pulled in.

Now, I am not making this up! Behind the counter stood a man that had to be 170 years old. He had a pure white beard that went down to his knees. He was wearing wire rimmed glasses, and NO he was not Santa Claus. He had his pure white hair cut G.I. style "to support the troops" he announced and he was stick thin. Anyway, I plopped my 25 year old motor on the counter and explained my problem. After a moments hesitation he picked up the motor and turned it over in his hands. "Uh huh" he grunted, then "Be back in a minute". He set the motor down and sauntered off into a back room.

A few minutes later he came back carrying a 1984 Mercruiser parts catalog (1984 for crying out loud!). He thumbed through the catalog for a few minutes and announced that my motors' Mercrusier part number was 14336A8.
He then picked up an Arco catalog, thumbed through it and showed me part #6218. This cataog not only showed the part, it also showed my Mercruiser pump that it replaced including the comparative mounting geometries! He had the motor IN STOCK! and $200.00 and ten minutes later I went home a happy man. Just goes to show...I had felt like I was entering enemy territory and the guy was exactly the kind of help I needed.

Thanks to all of you for your help with this. This motor is the last piece of the retrofit for the old boat. Next week I will have it transported to Gulf Shores, Alabama and commence with the maiden launch. I have been working on this project since August and I was VERY fortunate to find you guys. I look forward to having this forum as a highly informed resource for as long as I am in boating.

Thanks to all of you.
Phil

 

[ErieRon]

Re: Trim /Tilt Motor Replacement

Yahoooo !

Glad to hear all of that good news Phil...Great story.

Good luck & happy boating.

Ron