1988 mercruiser alpha 1 gen 1 steering issues

Steelguitarman

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Hello, I have a 1988 5.0 with an alpha 1 gen 1. Steering had been a little stiff this summer, but nothing unmanagable for a 25 year old set up. It wasn't untill this last fishing trip, it was a two hand job, very stiff. I chalked it up to the colder weather at first but after it warmed, it still was acting this way.

This is what I've done so far, disconnected the steering cable and cleaned the cable end and tube. This is very smooth now and helped alittle but not enough.

Disconected the outdrive steering arm pin, the outdrive swung easily.

I now know it's either the power steer valve or ram cylinder stuck. I took the actuator off and this is what I found. First, the ram cylinder moved freely. Second, after disconnecting the lines, a small circular disk with the consistency of Elmer's glue was between the fitting of one of the lines going from the valve to the cylinder. I think this was my major problem. I didn't tear it apart more and put it back together.

Drained all the fluid and put in fresh, it now turns much easier on muffs, but when turning the wheel fast, it almost has a shutter that reminds me of water hammering. I shut it off and let it cool, tried to bleed the system of air again. It still does it, but like I said, only when turning fast. When turning it normal it is smooth as can be.

My question is, is this shutter normal, sign of air still in the system? Is there something I've overlooked that would cause this? Does the valve need rebuild, or should I take it apart to see if any more of the gunk is in there?

Thanks for any input or advice.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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your steering cable is the primary suspect. and your boat is 35 years.

your power steering system is self bleeding
 

Steelguitarman

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your steering cable is the primary suspect. and your boat is 35 years.

your power steering system is self bleeding
Possible, the cable had been replaced in 2009, the helm looks like it was replaced too, but I don't see a date, so hard to tell. It is smooth both outside, and inside the tube when disconected form actuator. When shuttering, it is moving at with it at the actuator and making a slight audible sound.
Thanks
 

flashback

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I have no experience here but remember reading in a service manual that the flats on the actuator need to be in the vertical position or you can experience a symptom called feedback. FWIW
 

Steelguitarman

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I have no experience here but remember reading in a service manual that the flats on the actuator need to be in the vertical position or you can experience a symptom called feedback. FWIW
Can you explain to me what the flats are? I have the older style actuator with the 2 external lines. Wasn't sure if that applies here
Thanks
 

flashback

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Best I remember the tube that the cable fastens to has two flat areas on it that you put a wrench on to hold the tube in place when tightening the steering cable. You probably need to find a manual and it will explain it...
 

Scott Danforth

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The tube that the cable goes thru is the pilot shuttle for the power actuator

As the cable pushes out it does two things

First, the cable pushes on the tiller arm.

Second, the sheath pulls in on the pilot shuttle metering hydraulic power to the steering servo, which adds hydraulic power to the steering tiller arn

Turn the wheel the other way and the system works in reverse

If the cable has any binding, the system doesn't work as designed

If the pilot shuttle isn't aligned (flats), the system doesn't work as designed
 

flashback

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The tube that the cable goes thru is the pilot shuttle for the power actuator

As the cable pushes out it does two things

First, the cable pushes on the tiller arm.

Second, the sheath pulls in on the pilot shuttle metering hydraulic power to the steering servo, which adds hydraulic power to the steering tiller arn

Turn the wheel the other way and the system works in reverse

If the cable has any binding, the system doesn't work as designed

If the pilot shuttle isn't aligned (flats), the system doesn't work as designed
Thx Scott . that's a much better explanation
 
Last edited:

Steelguitarman

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Just ran out and checked and after looking at a few threads, I don't think mine has the flats. It's the older style and the tube for the steering cable is all round with a nut at the inner portion where it attaches to the stud arm.

I've attached a link to one that looks like mine

 

poconojoe

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I'm not sure from your original explanation if you disconnected the cable from the actuator to see if the problem was the cable.
Disregard if you already ruled this out.

Mine was like yours, so tight I needed two hands to turn the wheel. I thought it was old grease at the actuator, but when I disconnected the cable from the actuator the steering was still difficult.

I got numbers off the cable sheathing and ordered a new one.
I tied a piece of wire to the old one before I pulled it out. This way I could pull the new one in with the wire to ensure it passed through the correct route.
What a difference. The steering is so easy now.

Again, disregard if you already ruled out the cable.
 

Steelguitarman

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I'm not sure from your original explanation if you disconnected the cable from the actuator to see if the problem was the cable.
Disregard if you already ruled this out.

Mine was like yours, so tight I needed two hands to turn the wheel. I thought it was old grease at the actuator, but when I disconnected the cable from the actuator the steering was still difficult.

I got numbers off the cable sheathing and ordered a new one.
I tied a piece of wire to the old one before I pulled it out. This way I could pull the new one in with the wire to ensure it passed through the correct route.
What a difference. The steering is so easy now.

Again, disregard if you already ruled out the cable.
Yes, tested the cable in the aluminum tube with actuator disconected, and tested cable completely out of tube, both times extremely easy and no binding or pressure
Thanks
 

lastblast

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Jan 26, 2023
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Yes, tested the cable in the aluminum tube with actuator disconected, and tested cable completely out of tube, both times extremely easy and no binding or pressure
Thanks
Did you ever find out your problem? Or did you end up having to replace the Power steering actuator? Mine is leaking and the only replacements I can find are over $1100.
Someone out there has to be able to rebuild these or there must be another replacement part out there that works that isnt that expensive.
I have searched all over and cant find any shop on the internet that claims to rebuild these but I know there has to be someone.

Thanks
 

Drivewayboater2

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Aug 21, 2019
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I was told rebuild kits are out there.. old corvette and mustangs used these power steering units. Sooooo i looked on my google machine and have found some information. Im not there yet on my rebuild but my findings say yes you can replace seals and clean it up. Better than spending the bucks on a new or used unit. Good luck
 

Scott Danforth

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I was told rebuild kits are out there.. old corvette and mustangs used these power steering units.
no. you were told wrong

the actuator is pure mercruiser only.

the power steering pump on the other hand is just a saginaw pump used by nearly everyone ..... ford, GM, chrysler, BMW, mercruiser, VP, etc.
 
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