Friday, July 29, 2011

It Floats!!!

I ran it for about an hour the other night - not one leak, not one problem, smooth as silk. Let the sea trials begin!!

I'll have lots more to post - many of the repairs and modifications I made aren't yet posted, and I have some ideas for new stuff.......but for now, here she is, afloat and in her home:


Saturday, July 23, 2011

Engines Installed, and Exhaust Modificatioins

     Well, they're in and running! The biggest change from the stock factory configuration is the relocated exhaust, which I discussed in a previous post. Now, I have a few pictures of the space created between the front of the engines, and the water lift mufflers:

     The factory setup has far less room in front of the engines, but by reconfiguring the water lift muffler inlets, I was able to move the mufflers aft about 10 inches, creating almost a foot of space between them and the engines. Now, water pump service doesn't require removing the mufflers!! So, without further rantings and ravings on my part, here is the finished product:





     There is so much more room to work on them now, there is no comparison to the factory setup. I can stand to the side of either engine, and by removing just the two center exhaust hoses, I can stand between the engines, and access the water pumps, bilge pumps, and manifolds. Success!

Hatch Actuator Rebuild

     The engine room hatch lift mechanism is based on an electric linear actuator. I have read a few horror stories about these failing, so I thought it would be best to rebuild it before installing it in the boat. And it's a good thing I did, because when I opened up the gearbox, it was filled with water!
     What a mess. Fully disassembled, it looks like this:
     I took all the parts and washed them in my parts cleaner, and then assessed the gears and shafts for wear or damage. Fortunately, everything was in very good condition, with one exception. There is an override clutch built into the gearbox that uses 6 bearing balls, 2 dimpled plates, and a belleville spring for tension. When the actuator reaches the end of its travel, the override clutch allows the motor to keep turning, so that no binding or breakage occurs. It also emits a rather loud ratcheting sound, so the operator knows the travel limit has been reached. In my case, the balls in the clutch were no longer round, but had flat spots. Fortunately, I had a pack of 100 bearing balls from a previous project in stock, and they were the right size! (0.250" diameter).
     Once the clutch was rebuilt, I cleaned the housing and back plate:
     and reassembled the clutch:
     Then, I repainted all the components, cleaned and lubricated the gears, packed the housing with synthetic grease, and reassembled the actuator:

     Don't forget to also lubricate the screw and guide bushing at the top of the actuator, and replace the shaft seal. I also sealed the housing with a bit of silicone sealant, to keep the moisture out.
     As for the drive motor itself, I disassembled it, polished the commutator, lubricated the armature bearings, and reassembled it. It was clean inside, and the brushes had minimal wear, so nothing much had to be done here. Just need to install it now....

Friday, July 8, 2011

Arch Lift

     When the boat was shipped from Charlotte, the yard had to remove the radar arch, and secure it on the bow of the boat. Easy for them to do with 4 or 5 guys. When the boat arrived at my shop, I used an electric winch, secured to the peak of my EMT structure, to lower the arch to the ground. I brought it inside for the winter, so I could clean it up and prepare to reinstall it. So, to perform the lift, my brother and I made up a rope harness, and kept adjusting the lengths of the ropes until the arch hung just as it would once installed. Then, I used the backhoe to lift it into place:
     Once it was hanging an inch or so above the mounting pad, I applied polysulfide sealant, and we carefully lowered the arch into position. There are 4 bolts on each side, and each of them has an associated backing plate, made from 1/2" aluminum. Once secured, it was a simple matter to reconnect the wiring. The coaxial cables had been cut by the yard, so I had to crimp new fittings on the cables, and make up splices for the FM antenna and the TV antenna. The old GPS and radar antennas shown in the pictures have now been removed, and replaced with a Simrad GPS antenna and 4 foot open array HD radar. I'll discuss the new electronics in an upcoming post....

Saturday, July 2, 2011

Exhaust Modifications

     In the March 23, 2011 post, I talked about refurbishing the water lift mufflers. At the time, I had not carefully examined the location the factory chose for them. After a bit of research, and some careful measuring, I realized that the stock location was only an inch or two from the front of the engines. Note that when I say "front" of the engine, I mean the rear facing end, since these are V-drives. So, if any maintenance has to be performed, such as a belt change, water pump impeller service, water circulator pump service, etc., the mufflers are in the way.

     Now, there is plenty of room behind the mufflers, so it would seem to be an easy task to simply move them back 6 or 8 inches. But, an interference is then created between the 4-inch exhaust inlets, on the outboard side, and the larger underwater exhaust discharge piping. To solve this problem, I cut the existing exhaust inlets off the mufflers, and reshaped them to allow for the repositioning.

     To make the new bends I needed, I ordered a few lengths of 4 inch diameter, marine, fiberglass exhaust tubing. Then, using a fixture for my band saw, I cut a supply of angled wedges, as seen below:
     I cut these at either 10 or 15 degree angles, and then just stacked them until the desired bend was achieved. As I fitted them in the boat, I used a bit of Crazy Glue to hold them together. If an angle needed adjusting, I would simply break the wedge off, reposition it, and re-glue. Then, once I had the desired bend shape mocked up, I fiberglassed the mufflers back together.


    A few words of caution on a job like this. First, you cannot use polyester resin from the local hardware store!! Marine exhaust systems should be fabricated from Class 1, Isophthalic, fire retardant, high temperature resins. These are typically tooling resins, that exhibit good strength and thermal stability. I used Reichold DION ISO 6631T resin, available readily at www.mertons.com. These guys provide great service, fast shipping, and reasonable prices for small quantities. For cloth, I made it easy with a 100' roll of 1 1/2" wide, 8 oz. fabric.

     Once the angled sections were glued in place, I coated the inside and outside with a layer of resin, then wrapped the fiberglass tape around the first bend. It was a simple matter to then apply a bit of resin, wrap the tape tightly, apply more resin, wrap the tape, etc., etc. The finished layup is strong, tight, continuous, completely waterproof and leak free, and fire resistant. The laminate thickness now exceeds 1/4 inch where the new bends are, lending greater strength than the original tubing. The bends are nice and free flowing, so there will be no horsepower penalty or loss of efficiency. In fact, the new bends are actually superior to the factory setup, with the fiberglass elbows leading into the mufflers. I won't be using any of them for the exhaust on this boat. And best of all, I now have almost 12 inches in front of each engine!!! I can change belts and water pumps without removing the mufflers, and there is room to stand right in front of the engines. A huge improvement.....


     I'll post pics of the finished exhaust, in the boat, soon...