Perfect Pass throttle cable assembly replacement / repair

[swbca]

2004 Mastercraft Prostar 197 TT (Team Tournament)

• 350 HP EFI MCX Indmar engine

 

As shown in this photo, the cable assembly was kinked near it's connection to the servo motor. Its currently straightened with a "splint" made from two popsicle sticks, Tyvek-tape and wire-ties. PP support is trying to identify the assembly to sell me a replacement.

 

Where does this cable go after it connects to the assembly behind the air filter ? It continues toward the back of the boat under floor . . . does it continue all the way back forward to the Shift/Throttle control by the driver ?

 

I could mold a fiberglass w/resin sleeve to straighten and stiffen the cable where its damaged, but recognize the inner cable would still probably have a pressure point against the cable sleeve. I would probably do that if the alternative is tearing the boat apart to replace a cable all the way back to the driver's controls

 

(trading it for a ZO boat isn't an option today) The PP system is updated to last year's version with StarGazer and Z-Box and works great even when its held together with popsicle sticks.

[Mastercrafter]

Perfect Pass cable ends at your throttle body, and the cable continuing rearward is your OEM throttle cable to the throttle/shift control. The two cables screw together with the brass hexagonal barrel nut. PP should be able to get you their short cable easy-peasy.

 

[swbca]

Fantastic - What would BOS be without you ?

 

@Mastercrafter Unrelated question . . . look at the welded plug on the manifold. The prior owner had the boat since 2005 and said both manifolds developed leaks from corrosion. He had them welded and powder coated because there were no exact replacements at the time. There were replacements but with a problem . . like maybe they didn't fit under the motor cover. Is this common and should I expect more of the same ? Fresh Water use only since new.

[S1Pitts]

It looks to me that the servo motor cable is what needs to be replaced. The servo cable stops in the brass coupler that joins the OEM throttle cable leading to the hand controls.

[skihacker]

I had similar aluminum manifolds on a monsoon, several leaks developed over the years and jb weld always did the trick,

[Mastercrafter]

@swbca it'd surely be a better place without me but Horton hasn't banned me yet, ha.

 

I've heard of a lot of similar manifold leak issues but I'm not real up-to-speed on a fix or solution. While external leaks can be fixed, my larger concern would be internal leaks, leading to water in cylinders.

 

I'd give Bruce J at Action Watersports a call and pick his brain on replacement options - (810) 629-1342

[UWSkier]

Those are sacrificial plugs in the lightweight manifolds that replaced the cast iron lumps of a few years prior. They are known to corrode away and require patching and replacement. Shouldn't be a problem of water intrusion if they rot out. Just weld in new ones. Bakes sells them as do I'm sure any number of marine part retailers.

[swbca]

@UWSkier Does your explanation suggest there no related risk of an internal leak to the cylinders as Mastercrafter thought might be concern ?

[VermontSkier]

My ski partner has the monsoon with the similar manifolds and also uses JB weld with great success. I think he is on his third summer with the JB weld repair and they are holding strong.

[UWSkier]

@swbca I don't believe there's any risk of that as the locations of the plugs are on the external surface of the manifolds. If one of those plugs goes, the water just lands in the bilge. The internal separation of exhaust gas path and water path should not be compromised by one of these plugs failing.

[swbca]

Thanks, I wasn't sure if the sacrificial plugs were the only vulnerable point in the manifold design.

[BraceMaker]

That bend is WAYYYY to tight on the PP.

 

[Bongo]

@swbca, I've the same year, model and engine (and color?; navy on white boat) as you.

 

Here's what the PerfectPass cable you are replacing will look like: (two; one still broken)

 

Easy to swap out. And as has been said, only from the brass nut to the servo motor is what you'll change. Or fix; pretty simple.

 

 

Regarding the plugs on the exhaust manifolds, I had leaks form on a couple of my plugs. I used JB Weld two summers ago to get me to the end of the season. Once Autumn came, I took each exhaust manifold off, ground out each of the old sacrificial plugs (I did all, not only just the ones that leaked), and took the new plugs I had gotten from Bakes to a local welder who welded them in. Got everything back to the garage, used a rattle can to spray on the appropriate colored paint and installed them. If I recall correctly, I probably put $200 total into it and a few hours of labor. Straightforward.

 

Bongo

[swbca]

@BraceMaker are you referring to the factory installed bend that looks like a 4 or 5" radius or are you talking about the kink where I patched on temporary popsicles as stiffeners ?

 

the factory is sending out a 13.5" MCX cable which is the same as the one in the picture

($69 plus $22 shipping to USA)

 

How would you propose reducing the radius if you referring to the 4" or 5" radius bend in the picture ?

[DW]

@swbca - I made my own cable, easy DIY project, as I wanted a longer cable to allow a bigger radius and eliminate kinks. A good bike shop has all the parts to whip up what you need, the trick is the ferrule between the PP rope on the servo and the cable, I used a ferrule from the local hardware store (aluminum, brass or copper works fine). The end for the throttle blade connection is a bike brake / shifter cable end. As noted, JB Weld is a wonderful thing.

[BraceMaker]

@swbca I think I am referring to the "factory" install but I would state that set up is not good for a perfect pass - you'd want the maximum bend to be about half that.

 

You'd move the servo to wherever the bend in that cable is super gradual.

[swbca]

On this boat, not seeing a way to increase the radius (soften the curve) by more than a trace. The Cable is very close to the motor cover so the servo can't move forward. Lowering the servo doesn't change the radius without creating a tighter radius (kink) as it passes by the air filter.

 

Looks like Master Craft was doing the best they could without moving the throttle linkage backward in the boat which would require redesigning engine components or redesign the throttle linkage to move the OEM cable position back a few inches. I can see some very minor servo position changes, but the curve in the cable would only change very slightly.

[BraceMaker]

maybe cut a bit of radiator hose and shim the top hose clamp to lean it away? Anything you can do will improve that. Far too tight for PP. They may have insite.

[S1Pitts]

Maybe the answer here is a much longer PP cable and relocating the servo assembly? I have seen some super long ones on outboards.

[DW]

@swbca - The shrink tube coming from the throttle connection reduces the ability for the cable to start a bend thus reducing the radius. If you eliminate that and lengthen the cable, you open up your radius options even with the doghouse leading edge in current position. Am I missing something, I don't see a throttle return spring? Is is on the other side of the throttle body?

[swbca]

@DW The throttle return spring is a rotary coil with about12 windings. Not a compression or tension spring - the coil winds and unwinds. Its hidden in the photo. I am going to work on positioning when I replace the cable. Checking things so far. there is about 1" clearance between the servo motor and motor cover as it closes, so maybe can move it starboard a few inches.

[swbca]

Re repositioning the Servo Motor so the cable could have a longer radius bend . . . I have detached the servo motor and looked for options.

 

The limiting factor with the MCX engine in the 2004 ProStar is the distance between the throttle linkage and the front of the motor cover. The cable is right up against the motor cover on the factory installation so the cable has the softest curve that doesn't exceed the bounds of the motor cover. Even positioning in the servo horizontally, starboard of its current location still doesn't change the distance from the throttle linkage and motor cover. Also the motor cover latch mechanism only clears the Servo mount by less than 1 inch as the cover is raised and lowered.

 

I appreciate the suggestions to remedy the sharp curve in the cable but >>>>>

 

This boat like 100's of other others has been in use for 18 +/- years and the fully updated PP with Stargazer and Z-B0X works well in this boat. Its response doesn't seem to be burdened by friction from the curve in the cable. Welcome any further ideas.