OMC Electric Stringer Powersteering install

[HorizonblueDK]

My friend has a 1976 25 ft flybridge boat with twin OMC 165s. This has external steering-rams, one on each drive, connected to each steeringwheel and a bar between the drives.

This boat is a bear to steer in the marina, since it's very heavy work to turn either steering wheel. So he asked if it was possible to add powersteering. I believe it is.

I see it this way.

1. remove all the old steering stuff; both cables, helms, external rams etc. (leave the bar between the drives)

2. Install steering gear in one outdrive and the special powersteering gearbox on the intermediate housing, along with hydraulic ram, oilcooler, pump etc.

3. install new teleflex helms/cables, and somehow fabricate brackets so both cables can be connected to the powersteering cylinder.


Any thoughts on this job?

It would of course be easier to control the powersteering with hydraulic steering, since it is easy to connect two helms to one cylinder, but that is gonna be to expensive, and it's not really a problem to fabricate special brackets.

Are there any flybridge boats out there with teleflex steering and e.g. Mercruiser drives with powersteering? They must have two teleflex cables connected to one powersteering cylinder, could be interesting to se how that's done.

I already have the OMC powersteering gearbox and steering shaft for that one.

Only the mech stringer had powersteering as far as I know, but is there any major difference between the intermediate housings that makes it impossible to mount the powersteering gearbox on an old intermediate housing? Still, it's no problem to fabricate special brackets.

 

[Bondo]

Re: OMC Electric Stringer Powersteering install

Ayuh,.. If it's got the old Tru-course steering,... Forgetaboutit....
It'll be either Full Hydrualic, or nothin'....

 

[Howard Sterndrive]

Re: OMC Electric Stringer Powersteering install

This has external steering-rams,

OMC never had any kind of external rams steering their drives, so what is there may already be aftermarket unless you are just calling the cable ends "rams"...
"ram" kinda says hydraulic to me though

Tru-course was an option in 76, but not a popular one. Most 1964-1977 stringers had a mechanical rack and pinion cable assembly that had a cable mount in a clamshell arrangement on the transom and a link arm to the exhaust housing of the drive to steer it.

Tru-course setups did have a power steering option for V8's, but it was not popular...had a gear box affair mounted to the intermediate -a "torque amplifier" that drove the trucourse steer shaft. would be eBay or wrecking yard score in this day

Not all pre-1977 drives can accept tru-course steering gears. Some upper gear cases were not finish machined inside where the steering parts go.

best idea is to just fix whatever is there.

One common cause of tight stringer steering is improper shimming of the upper gearcase into the exhaust housing. There are shims that go onder the top exhaust cover to control how tight the upper is in the lower.
Also there is an often neglected grease fitting for steering on the front side of the lower unit...sounds like this one needs grease

the condition of 35 year old steering cables on a flybridge boat could be dodgey too.

 

[zbnutcase]

Re: OMC Electric Stringer Powersteering install

I totally agree with Howard; best idea is to fix whats there, the power steering parts for stringers are really hard to find.

 

[HorizonblueDK]

Re: OMC Electric Stringer Powersteering install

Tru-course was an option in 76, but not a popular one. Most 1964-1977 stringers had a mechanical rack and pinion cable assembly that had a cable mount in a clamshell arrangement on the transom and a link arm to the exhaust housing of the drive to steer it.

One common cause of tight stringer steering is improper shimming of the upper gearcase into the exhaust housing. There are shims that go onder the top exhaust cover to control how tight the upper is in the lower.

Yes, this is how the steering is now(rack and pinion). Ram was the best word I could think of, for describing the end of the cable, coming out trough the transom.

There are two of these "rams" on the transom, they are connected to each drive.

This is a brochure photo of the actual boat, where the setup can be seen. You have probably never seen this boat in the US

When both "rams" are taken of, the drives turns very nice and easy. But when the whole thing is mounted, the wheel is heavy to turn.

The outdrives are actually ready for "tru course" steering, I had them opened some time ago, the worm gear is there already, the worm wheel has been removed, so the external steering could work.

I have purchased this on ebay:


So if I find a worm wheel and install it in one drive, and this gearbox on the intermediate housing, most of the hard part is over, I guess.

I'm going to use a hydraulic ram from an OMC Cobra along with a home made bracket, since the original ram and bracket was not included.

After that, I will install new teleflex mechanical helms and cables, and now for another "fun" part.

How to connect teleflex cables from two helms to one powersteering cylinder?

Has anyone ever seen that?

This whole project may sound totally crazy, but I like challenges

 

[Howard Sterndrive]

Re: OMC Electric Stringer Powersteering install

should work ok as long as at least one of the drives has the machining to accept trucourse steering worm gear and such.
still don't get why you don't want to diagnose it. I suspect it steered just fine in 1976 without power steering.

 

[HorizonblueDK]

Re: OMC Electric Stringer Powersteering install

should work ok as long as at least one of the drives has the machining to accept trucourse steering worm gear and such.
still don't get why you don't want to diagnose it. I suspect it steered just fine in 1976 without power steering.

I have a test of the boat, from when it was new in the mid 1970's, and here the test team actually mention that steering the boat is pretty hard work, probably because when you turn either wheel, you have to move approx 30 feet of cable and another helm(and sterndrives).

Of course it gets worse over the years, but I think the time has come for this old system. There must be a better option.

One could say that if I still use teleflex cables(allthough new) it will continue being a bear to steer. But I believe that if they are both connected to the powersteering cylinder somehow, the powersteering will assist in pulling the cable for the helm that is not being operated.

 

[Bondo]

Re: OMC Electric Stringer Powersteering install

the powersteering will assist in pulling the cable for the helm that is not being operated.

Ayuh,... That's a False assumption...

P/S only powers the push of the tiller...
If the problem is Cable related, yer gonna be terribly disappointed...