Changing Engine Control Cables on a Mark I

[Mike and Theresa Vaccaro]

Changing Control Cables on a C34 MKI – Lessons Learned   

1.   There is a Tech Tip on the Edson website that details the removal and replacement of control cables in Edson pedestals.  Be sure to download and read it carefully before proceeding.
2.   Clean out your aft stateroom/storage shed and remove the teak bulkheads.  Not strictly necessary, but it will make replacing the cables a whole lot easier.  As a minimum you'll need to remove the fiberglass fairing over the turning sheaves at the base of the pedestal and the access cover under the aft berth (for access to the clutch lever).  
3.   Since you're going to have to remove the top portion of the pedestal (including the compass), this is a good time to perform any required preventative maintenance on the steering system and engine controls.  If you haven't updated to the new, stainless engine control levers, this is the perfect time to do the job.  Edson also publishes a pedestal maintenance guide.  It is available for download, or you may order a copy by calling Edson.  They also sell a maintenance kit that includes most common components.  The Edson maintenance guide describes how to inspect and repair the engine controls.  You may consider ordering replacement ¼ x 20 mounting screws.  If you have an older boat, odds are high that the old screws may have corroded.  New screws have a Phillips head as well as a coating that aids in preventing future corrosion.
4.   To remove the binnacle compass, first loosen the two screws that hold the light assembly in place.  Lift the stainless portion up, and slip the light wire out of the grove that holds it in place (you may leave the light hanging throughout the maintenance process, but consider taping it to the pedestal to prevent damage—the alternative is to cut the wires and splice them during reassembly).  The next step is to remove the four screws that hold the engine control housing in place.  To access the screw heads, loosen the screw that tightens the collar around the base of the Ritchie SP-5 compass.  Lift the compass out and set it aside.  Older pedestals have slotted screws.  If you cannot loosen the crews with a large slotted screwdriver, they have corroded to the base.  It's very difficult to use an impact screwdriver, since the screws are likely to twist (only the last inch or so of 4" screws are actually mated).  You may be able to grab the head with a small vice grips and get the screw started.  If you are unable to remove the screws, the only alternative is to cut the head off.  This is most easily accomplished with a Dremel tool and a cut-off wheel.  It will be almost impossible to accomplish this without damaging the plastic base of the compass.  If necessary, you can obtain a replacement base from the E.S. Ritchie company (the phone number can be accessed from their website) for about 20 dollars (you'll need to save your compensator screws and hardware though, so keep the old assembly until your new base arrives so that you can transfer the parts!)  Once the screws are removed or the heads cut, you can lift the engine control assembly off in accordance with the Edson instructions.  This will leave the remainder of the screw studs exposed.  A good douse with penetrating oil and vice grips as close to the base as practical should do the trick to remove them.  If a screw snaps off flush with the housing, you'll have to drill it out and re-tap.  
5.   The cables that Catalina sent for replacement were the wrong length.  They sent a 15 and 16 foot cable for the clutch and throttle respectively.  An 11 and 12 foot cable are more than adequate for a 1988 vintage Mark I.  The trick with control cables is to avoid all bends to the maximum extent practical, and make the unavoidable bends as gentle a radius as practical.  In our boat, the factory installed two twelve-foot cables, but the clutch cable had unnecessary s-turns, increasing friction and wear.   The Teleflex cables can be obtained from any good marine outlet as well as Catalina.
6.   It's necessary to slack the steering cables and lift the steering chain out of the way to remove the cables from the pedestal.  The procedure for removing the cables is detailed in the Edson tech guide.  To loosen the steering cables, you'll need access to the top of the rudder quadrant.  This may require the removal of your propane locker and the shelf that it sits upon.  The cables terminate at two large stainless eyebolts and are retained by common cable clamps.  If your clamps are corroded, now is a good time to replace them (stainless clamps are available).  To loosen the cables, feel under the quadrant to find the end of the eye bolts.  Use a ½" wrench to remove the stop nut, and then loosen the retaining nut.  I removed them completely and then slide the cables off the quadrant and sheaves below decks to allow for maximum slack in the cables.  This will allow you to lift the chain up and forward and provide a maximum amount of room in the pedestal to remove the cables and the cable retainer.  Instructions for removing the cables themselves are in the Edson Tech Tip.
7.   Remove the cables from the clutch and throttle assemblies at the engine.  You'll need to reuse the pins and setscrews with the new cables.  Note whether or not your clutch cable is hooked up to the outer or inner hole.  Some older installations with the composite control handles may utilize the outer hole.  Catalina recommends the inner hole to obtain maximum throw from the control lever.  If you are switching to the newer stainless clutch lever, this will be necessary to obtain sufficient throw to put the engine in forward.  This is detailed in Catalina drawings (albeit for a -100 transmission on the M-35 vs. the -50 on the M-25, however, the geometry is the same), and thoroughly described in other threads on this forum as well as on the Catalina 36 website.  Do a "search" or "find" for "engine control lever."
8.   The Edson guide calls for using the old cables as messengers for running new cables.  If you've removed the aft bulkhead, a messenger is almost unnecessary, but a light line can be tied to the end of the old cable at the base of the pedestal before you pull it up, to ensure the new cable crosses the chain and the electrical wire to the compass light in the same manner as the old cable.
9.   Hooking up and adjusting the new cables.  The throttle cable is retained with a simple flip clip and the clutch cable is retained by 2 #10 screws, nuts and a two-piece retainer that mounts to the afte end of the bracket bolted to the transmission housing.  Be sure to use split washers or self-locking nuts on the #10 screws to prevent them from vibrating loose.  It's possible to "fine tune" the cables by adjusting the pins, but not really necessary.  Ensure that you have adequate throttle throw to move the lever between the idle and maximum set screws and make sure that the clutch lever is in the middle of the neutral detent.  That's about all that's required.  You may find that the clutch lever hits the pedestal guard when shifting to forward.  This is of no consequence if the clutch lever is out of the neutral detent (lever on the transmission moves AFT when shifting into FORWARD gear).  There is no forward or aft detent, only neutral on the Hurth transmission.  Be sure to adjust the throttle friction nut to ensure that there is adequate friction (throttle will tend to drift toward IDLE with inadequate friction).
 
The most difficult part of the job was removing the corroded screws.  We had two that refused to budge and had to be cut.  One subsequently snapped and required drilling.  Since your steering system will be largely disassembled, take the extra time to do preventative maintenance and lubricate as required.  Be sure to check the play in the bronze pins that retain the turning sheaves at the base of the pedestal (a common wear point).  

Cheers,

Mike

[Mike Smith]

Vac -

Very timely!  I'm replacing my entire pedestal due to gauling of the stainless bolts where they mate with the aluminium binnicle.  I may need a consult when I slack/remove the steering cables and chain, etc.  The problem arose when I added my angled pedestal.http://www.c34ia.org/phpbb/viewtopic.php?t=1489&highlight=angled+pedestal

Mike

PS Hope you made out OK with Frances. We haven't gotten a drop of rain yet!

[John Langford]

Mike Smith mentioned problems between the SS bolts holding down the pedestal and the pedestal base. The white paint on my base is erupting in several spots contiguous to the bolts. I have looked at the Edson site and retrieved their advice re repainting. However, I would be interested in knowing whether this has been a particular problem with Mk IIs and what can be done to stop whatever is happening there from happening again.

Cheers,
John

[Stu Jackson]

John

It sounds like galvanic corrosion to me.  A little Lanacote (or is it Lanocote?) or TefGel between the bolts and the pedestal should help.