The Problem
We motored out of Bocos del Toro on a Sunday afternoon for a casual 130nm passage east, with a planned stop in the Chagris River, just 6nm west of the Panama breakwater entrance. After a pretty choppy night with winds shifting forward of the beam and dragging us closer to the coast we decided to switch on the engines to help us come back up on to course. We had been a bit lazy and only had a headsail out so we could not work our way up higher under sail. Keith started the starboard motor first. As usual gearshift lever was in the vertical / neutral position, but the engine started in gear, with the throttle fully open and immediately shot up to 3000rpm! Holy crap!
He instantly switched the engine off thinking something was seriously amiss. Luckily we have two engines… He started the port engine and exactly the same thing happened – straight up to 3000RPM. He tried pulling the throttle handle back towards himself to reduce the revs, knowing that this would usually engage reverse gear, but the handle would not move backwards at all. He then very gingerly moved the throttle forward (which would normally increase the revs) and lo and behold the RPMs started to come down until in fully forward position when the motor idled. Hmmm well at least we had engines working albeit in forward gear only.
He instantly switched the engine off thinking something was seriously amiss. Luckily we have two engines… He started the port engine and exactly the same thing happened – straight up to 3000RPM. He tried pulling the throttle handle back towards himself to reduce the revs, knowing that this would usually engage reverse gear, but the handle would not move backwards at all. He then very gingerly moved the throttle forward (which would normally increase the revs) and lo and behold the RPMs started to come down until in fully forward position when the motor idled. Hmmm well at least we had engines working albeit in forward gear only.
Trouble Shooting
We gave up on the idea of the Chagris River, with its notorious keel-claiming reef near the entrance, and lack of phone reception, and decided to head for Panama and the Shelter Bay Marina. We continued motoring with 2 engines on at about 1800RPMs as by now we are punching into some reasonable wind and waves. As we got through the breakwater we radioed the marina, but they weren’t quite ready for us to come in with engines that would only go forward, which was probably a good thing. We motored over to The Flats anchorage, just outside the marina and dropped an anchor, which was a challenge in itself given the 20kts trade winds blasting through the harbour entrance and having no reverse gear, which limits our manoeuvrability. We got some concerned looks from one boat anchored nearby, and its times like these you think that you must look like an amateur! Once anchored and with engines off Keith started playing around with the throttles, he tried pulling the handle horizontally outward on the starboard engine, which would dis-engage the gear shift, and moving the throttle lever forward and backwards. He wasn’t quite sure what he was doing but just doing stuff hoping that something might slip back into its correct position. Well that went well and after around 10 minutes of fiddling he was suddenly able to engage reverse and had the starboard throttle operating normally. Phew.
Bouncing off the dock
Now trying to remember what he did right, he started on the Port engine. Sadly however it ran straight to 3000rpm and the handle was locked in the vertical position and would not move in either direction. Well at least we have one engine. We motored into Shelter Bay Marina and managed to dock Itiki starboard side to, on starboard engine only with 25kts over our starboard aft quarter. With some help from Tad of SV Bisou pushing us from the port side in his dinghy, and JuanJo and his boys on our lines, we only kissed the dock gently with starboard bow (the scratches polished out…)
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No pressure, but we are actually on the Port Authority dock and they are not too happy, so we have to get off as soon as possible. There is a berth available for us, but manoeuvring into it with one engine is just not gonna happen! So let’s see what we can do to trouble shoot this problem and get it sorted! The thought of cancelling our Canal transit, as well as the knock on effect for the Galapagos dates is hanging over our heads as well. No Pressure!
Overnight we consult the font of all wisdom – the FP Owners FaceBook group. Immediately we find that we are not the first to have this kind of problem, although most people seem to have it with one engine at a time.... We are eternally grateful for this group and the owners who take the time to take and post photos of their problems and how they have fixed them. Why would both throttles pack up at exactly the same time when they operate independently!?
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No pressure, but we are actually on the Port Authority dock and they are not too happy, so we have to get off as soon as possible. There is a berth available for us, but manoeuvring into it with one engine is just not gonna happen! So let’s see what we can do to trouble shoot this problem and get it sorted! The thought of cancelling our Canal transit, as well as the knock on effect for the Galapagos dates is hanging over our heads as well. No Pressure!
Overnight we consult the font of all wisdom – the FP Owners FaceBook group. Immediately we find that we are not the first to have this kind of problem, although most people seem to have it with one engine at a time.... We are eternally grateful for this group and the owners who take the time to take and post photos of their problems and how they have fixed them. Why would both throttles pack up at exactly the same time when they operate independently!?
Lifted out, better mask around the area to avoid scratches
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Pic #1: Cracked open like a coconut, note all the Sika
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Pulling it all apart
The first step was to remove the gear/throttle assembly, which had been bedded to the helm post with so much Sika that we could have lifted the boat out of the water by the handles! Masking up around the unit was a good idea to avoid scratching the gelcoat in this area when removing the assembly, as there is very little slack in the cables and it needed to rest on the edges of the helm console. Keith split open the 2 halves of the black box like a coconut (Picture #1) and the first thing he noticed was a screw hanging loose. As he reached for it disappeared down the centre of the helm console never to be seen again. Fortunately having 2 units with one of them now working correctly it was possible to see what the mechanism should look like. Picture 2 shows the faulty (port) one with the throttle linkage at 90 degrees different. Picture 3 shows the functioning starboard one, (ie what it should look like) with the throttle linkage vertically aligned.
Pic #2: Port side, faulty one. Note 90 degree angle of the arm
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Pic #3: Starboard side, functioning one. Note correct vertical alignment
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The main metal arm from the centre should be vertical and the guide pin (not visual as it is on the other side of the arm) should be engaged in the slot of the white nylon housing at the bottom. Unscrewing the arm to realign the unit Keith noticed that the pressure pad under the small rectangular metal plate on the left hand side was not seated correctly (see picture 3) The pad is in tension from the curved vertical steel springs under the small plate. Whilst trying to reassemble the mechanism he could not get the white nylon housing to settle into its correct position, handy having the other unit to make comparisons. Fiddling, muttering (ok… swearing) and cajoling trying to align the unit a ball bearing dropped out. Whilst he hadn’t seen any signs of ball bearings I remembered that on the FaceBook forum someone had mentioned ball bearings. So what had seemed a fairly straight forward job where he could see all the components and could apply a little logic as to how to reassemble it all now changed.
Keith laid the faulty controller on its back and carefully undid the 2 bolts holding it to the outer housing and gently prised the 2 nylon housings apart and located the other ball bearings. There were only 3 ball bearings there plus the one that had escaped. He assumed that the 3 were in the correct position so it was just a case of trial and error to locate the correct position for the 4th. He wasn’t willing to pull the fully operation starboard assembly apart to see where it should go. The correct position became obvious as he tried to re assemble everything as it just slipped together easily. He applied plenty of grease and used Loctite to all the screws to hopefully ensure this doesn’t happen again.
Keith laid the faulty controller on its back and carefully undid the 2 bolts holding it to the outer housing and gently prised the 2 nylon housings apart and located the other ball bearings. There were only 3 ball bearings there plus the one that had escaped. He assumed that the 3 were in the correct position so it was just a case of trial and error to locate the correct position for the 4th. He wasn’t willing to pull the fully operation starboard assembly apart to see where it should go. The correct position became obvious as he tried to re assemble everything as it just slipped together easily. He applied plenty of grease and used Loctite to all the screws to hopefully ensure this doesn’t happen again.
ANy Lessons?
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To misquote Lady Bracknell** “To lose one throttle may be regarded as a misfortune; to lose both looks like carelessness.”
So what caused both throttles to fail simultaneously, given that they are completely independent of each other? The assumption is that the screw that came out of one unit (due to vibration over time and no Locktite) got caught in the second unit causing it to get jammed at as well. On a catamaran you do feel like you have some built in redundancy with two engines. When our starboard engine MDI failed of course we were not so worried as we had the port engine to rely on (plus a sneaky MDI bypass switch…). Having two engines, 24 feet apart, also makes for one very manoeuvrable boat. Cats can turn on their own length. Never again should we take that for granted, it’s pretty tough to steer a cat with only one engine, even when anchoring. Oh well, another day in the life of as boat owner! **The Importance of Being Ernest by Oscar Wilde |
