Vintage (1971) OMC Tru-Course Steering systems

[rcmedic]

I have a 1971 Combo Cruiser that I am in the process of restoring. Restomod is more accurate but I am needing a manual or any other documentation that might be available for the OMC Tru-Course steering system if one is available. Can anyone point me in the right direction please?

 

[southkogs]

Welcome aboard:

There used to be a small manual that referenced TruCourse, but it wasn't very complete. A service manual (you can still find 'em) would have the same level of detail on it.

Are you adding TruCourse? The boat on your site doesn't have TruCourse on it.

 

[garbageguy]

Interesting project! Exterior pic of front (bow?) perspective reminds me of the thing the Robinsons cruised around in on land and sea while on some strange world.

 

[Scott Danforth]

I would re-do the transom and go with either a late-model Volvo or late-model Mercruiser and remove all the OMG stuff myself.

if you need a factory manual, you order them from Ken Cook co. https://www.outboardbooks.com/

 

[kenny nunez]

There was a safety issue with the internal worm and spur. The stainless snap ring that retained the rear plug in the upper gear case was known to pop out as a result of either granular expansion or hitting a submerged object. Then the worm came out and you lost control. A re-call item was made that reinforced the area with a flat plate that mounted where the water passage cover was. It was formed to back up the plug that was part of the kit.
To tell you the truth the Tru-Course was a PITA to repair.
The safest steering would be the style that protruded from the transom and attached to the exhaust housing.
But the BEST thing you can do is follow Scott’s advice.

 

[rcmedic]

As far as I know the only part the is aTru-Course steering product is the helm RideGuide stuff as it is a rack & pinion on the front end. I have not really dug into the aft end yet as I am finishing up the front end. The helm is something that I have built from scratch.

 

[Scott Danforth]

the Helm is a teleflex unit (Now SeaStar Solutions). nothing OMG about it.

the Tru-Course is the name of the gear sector steering on the drive.

Hint: Kenny was an OMG dealer for decades and knows his stuff.

replace the drive/motor with something from the last 2 decades
replace the helm and cable with new.

 

[southkogs]

The helm had TruCourse on it sometimes even when it wasn't ... I can see the through transom push rod in the photos on your website. Same steering system as I had. The drive in the photos definitely doesn't show TruCourse (TruCourse is all internal on the Stringer drives).

If your drive is functional, the electric shift is working and seems to be in good shape, then I wouldn't be afraid of it. If the drive is questionable or a wreck, then do a serious gut check on converting over like the guys are advising.

 

[rcmedic]

Thank you Scott. I was going entirely by the label on the ride guide gage/bezel that has OMC Accessories Printed on it. So far as the outdrive and engine for that matter, both are in very good condition and seemed to work very well (in a test tank). I will have to rebuild the two carburetors as the accelerator pumps are apparently virtually dead.

 

[southkogs]

There are some positive things about the Stringers, but while you've got the boat all torn up you should consider doing the repower. It will save you some trouble down the road.

I like the Stringer drive, and I even like the electric shift. But the truth of them are they are vintage antiques. Parts are getting harder to get hold of, more and more marine techs don't know them (and some refuse to work on them). It will require attention in the garage, and if you're keeping the boat in a slip I would bet on water intrusion in your upper gear case within two years.

 

[Scott Danforth]

You mention two carburators.....such as plural.

That means you have the short lived 120hp, 2.5 liter with twin carbs

Valuable....no
Reliable....no
Complicated....yes

I would pull it in a heart beat and redo the transom for a 4.3/alpha setup or a 3.0/alpha

 

[rcmedic]

You are correct Scott.

 

[kenny nunez]

The Carter carburetors on the 120/2.5 Have shims to restrict the movement of the accelerator pump action, if they are not there the it effects off idle operation. The metering rods are different from the auto and are marine specific. Try to get the marine kits.

 

[rcmedic]

Thank you Kenny. Any chance you can share any other info or documentation? I am a highly proficient mechanic and would like to have a crack at it before I seek other options.

 

[kenny nunez]

Barr has a replacement manifold that uses the 2 barrel Rodchester for the 73 and up models. Finding rebuildable marine version should be easy. A little creative plumbing to connect the exhaust should not be too hard. Connecting the throttle may take some work but you should be able to make it happen. I have not tried to get parts for the Carters for many years as they were phased out in 73. Those Carters are the same body as the ones used on the Ford Maverick. It may be possible that someone replaced the original Carters with the auto versions, if there are no shims restricting the accelerator pump stroke then that may have happened.
I closed my shop in 03 and by around the late 80s that version of OMC systems were long gone.
There are probably still some survivors up north in fresh water areas.

 

[Scott Danforth]

the single carb on the 2.5/3.0 was so much more of an improvement