1969 Chris Craft Roamer Refit: Installing the Port Engine

Having installed the starboard engine, I learned many of the pitfalls to avoid and a few tricks that make the job easier. Installing the port engine should be much easier.

Read, set…GO!

Sleeping Beauty

Aside from rolling the engine over every few months, the starboard engine hasn’t budged since we craned everything into the boat through the salon roof hatch back in 2012. There’s a special tool for turning over Cummins engines, but I saved myself $50 and just bar it over using a wrench on the alternator pulley bolt. The pulley gives ~3:1 mechanical advantage, so I don’t even need a breaker bar to rotate this high compression diesel engine. It’ll be nice when I can just turn the key on and fire it up.

Lining up my home-built gantry with the propeller shaft

Floors braced…ready to lift

Once lifted, I can move the 1-ton engine with one hand

My custom-made shaft positioning tool

It might look like just some cobbled-together blocks of wood, but my shaft positioning tool is designed to rigidly hold the shaft in place even if it gets tapped by the gear coupler. A block on the bottom allows me to clamp the whole thing to the stringers, and I used a hole saw to make a cut-out on the top  block that just fits the shaft. Once I get the shaft aligned in the log side-to-side, sliding the tool back and forth on the stringers adjusts the height.

Dial indicator makes centering the shaft super easy

First, I position the dial indicator then let the shaft drop until it hits the bottom of the log. I take a reading, then I lift the shaft straight up until it hits the top of the log. Take another reading, subtract to find the distance to within 0.001″, and divide that number in half…there’s your center. There was .240″ total clearance, so I raised the shaft 0.120″ from the bottom of the log, and locked down my shaft positioning tool. Doing this on the port engine took the better part of a day. This time, with my fancy tools, it took about an hour.

Original engine bed boxes have to be cut out

One quick pass with a circular saw just about does it

One thing I really like about aluminum is that you can cut it using carbide woodworking tools. With a sawsall, it took the professional “marine engineer” who failed to install the engines in 2012 about 20 minutes to cut off one of these boxes. So instead of using a metal cutting blade on a sawsall, I just use a circular saw blade that’s intended for demolition work to make a long cut through the weld.  With my circular saw, it took about a minute for the first cut.

One minute with my Harbor Freight sawsall does the rest

In the pic above, you can see that I clamped a 2×4 to the stringer. I used that as a guide to keep the line straight when I made the cut with the circular saw.

All four engine bed boxes cut off in 25 minutes

Custom engine alignment tool: framing square clamped to a piece of aluminum angle at the halfway mark

Front engine mount needs modification, same as the port side did

I know from installing the port engine that with my down-angle ZF 280A gear, the engine will sit nearly level with the stringers when it’s finally in place. So I’ve got to have the vibration isolator landing pads on the front engine mount cut off and raised 3/4″, with the slot cut inboard by about an inch from the original.

Inner rear mount needs machining, too.

After blocking the engine above the stringers, I dropped the mounts off at a local machine shop for modification. In this one day, I accomplished what took three weekends the first time around on the port engine. Once I get the mounts back, I’ll clean them up and paint them, then scrub the engine bilge, grind off the remnants of the welds from the original engine beds, and make the spacer blocks for the vibration isolators. I’ll wrap it up by painting the stringers and bilge with Devoe Bar Rust 235 epoxy coating, positioning the engine, final alignment, and then I’ll bolt it all in place.

Next up in our 1969 Chris Craft Roamer Refit: Installing the Port Engine II

 

1969 Chris Craft Roamer 46 Refit: Cummins Engine Install — Coating the Stringers & Final Fit

With the vibration isolator landing pads done and motor mounts modified, the last step to getting this engine resting in its ultimate location is to epoxy coat the stringers and do the final alignment.

New forward vibration isolator landing pads are on the same plane on both sides

After the last test fitting, once I had the gear and shaft couplers aligned to within 0.005″, I marked the holes for the vibration isolator bolts. After moving the engine out of the way with the gantry, I drilled an 1/8″ pilot hole then used  increasingly larger drill bits until I finally opened up the 1/2″ hole.

Rear vibration isolator landing pads spread the load

New Moroso 400w oil pan heaters should keep the engines toasty in winter

I’ve had these oil pan heaters for a while, so it was nice to finally install them. Truth be told I almost forgot about them (like when I left the washer in the aft stateroom head), so it was good that I remembered before bolting the engines down for the last time. After taking the pic above, I ran a bead of high temp RTV around the perimeter of the heater to seal the edge. The Cummins 6CTA marine oil pan made it a bit challenging to install since it doesn’t have a flat bottom. These heaters have to be in 100% contact with a heat sink or they burn up. Even little bubbles caused by a surface that’s not perfectly flat might cause it to fail, so I broke out the sander and knocked it back to flat and smooth bare metal. Why anybody thought it was a good idea to put the company logo on the bottom of the oil pan is beyond me but it’s gone now.  🙂 The heater pad seemed to conform to the shape just fine.

With the holes drilled and pan heater installed, it’s time to bust out the stinky Devoe 235 epoxy coating.

Rolled and tipped Devoe 235 epoxy coats the assembly

Devoe is super tough stuff, but it’s an industrial coating so it doesn’t roll and tip to a pretty finish. But for the engine room, I’m more interested in protecting the metal than super shiny gloss. In addition to coating the stringers and landing pads, I also put another coat in the engine bilges.

Devoe 235 epoxy-coated front stringer and engine pan

Epoxy coating is done. It should be adequately cured in 24 hours.

Tefgel on all 316 stainless vibration isolator bolts

Tefgel lubricates threads, prevents galling, and controls corrosion. With the inside of each bolt hole coated with Devoe epoxy, direct metal to metal contact shouldn’t be a problem. But Tefgel is cheap insurance.

Front vibration isolators…DONE!

Rear vibration isolators…DONE!!

Shaft alignment is within spec, but the DriverSaver hardware isn’t!

Having paid $300 for a chunk of rubber, I expected Globe to send the right size bolts with its DriveSaver kits. But they use 1/2″ bolts instead of the 5/8″ ones ZF used for the gear coupler, so I had to buy an adapter kit. But the bolts that came with the DriveSaver kit are so short that only one thread sticks out past the lock washer on the gear-side of the flange. Also, the instructions for these Made-in-America rubber donuts were completely wrong: the gear flange is male, but the instructions say it should be female, and the bolts are completely different from the male to female side of the Drivesaver. I emailed the company and showed them the problem. We’ll see if they respond.

Longer bolts on the gear flange side should solve the problem; prop shaft-side bolts seem fine

In spite of this latest minor setback, the engine is in its final resting place. I can wrap up the DriverSaver install when new, longer bolts arrive. So that’s a wrap for the heavy lifting.

Time for the gantry to get out of the way

I’m really pleased with all of the space around this engine. Maintenance should be a breeze (crossing fingers here).

It took less than 10 minutes to disassemble the gantry

I cannot tell you how nice it is to have floors back in the salon!

Et voila! Done! (sorta)

The fuel system is 75% done, since I ran the supply and return tubing when I installed the hydraulic steering. The electrical will be a good project for the winter or, more likely, next spring. I plan to install the other engine and wrap up the exhaust systems before winter sets in again. But for now, I’m calling the starboard engine install a wrap.

Next up in our 1969 Chris Craft Roamer 46 Refit: The Aft Deck Hard Top (again)

1969 Chris Craft Roamer 46 Refit: Cummins Engine Install – Shaft Alignment and Front Engine Mount

I’m getting closer to having the starboard engine and gear finally aligned with the prop shaft coupler. But even with the locknut removed from the front vibration isolator and the adjuster nut completely bottomed out, I still have a 0.005″ gap between the couplers on the bottom. So the engine has to drop even lower at the front, which means the front engine mount needs modifying.

Cut off the original engine mount landing pads

Weld in a 3/4″ spacer and new landing pad (the vibration isolator is installed upside-down)

With the 3/4″ spacer welded on top of the remainder of the 3/8″ landing pad that was still attached to the mount, the bottom of the new landing pad  is 1-1/8″ higher than the original. That should give me plenty of room to reinstall the vibration isolator locknut and still have lots of adjustment to lower the front of the engine.

Ready for paint

Reconfigured engine mount looks good

Vibration isolators land in the right spot and the locknuts are installed

When I lowered the front of the engine to align the prop shaft and gear couplers, it became obvious that something was hanging up. The rear of the engine went up as the front went down!

Need more material removed from the transverse frame under the oil pan

After trimming off another 1/4″ of material from the top of the frame I now have all the clearance I need to get the couplers aligned. But first, I need to center the prop shaft in the log and lock it down.

A hole saw and some scrap lumber make a jig that maintains shaft position

Clamps keep everything locked down

Aluminum scrap wedge from the transverse frame I trimmed works as a gauge

Insert the gauge…need to raise the shaft so the gauge goes in to the mark

I tried using a dial caliper to align the shaft, but it was a real pain. The tapered gauge approach worked much better.

Right to the line on the top left

Close to the line on the top-right…split the difference by moving the shaft left just a touch

Right to the line…the shaft is centered in the log

Couplers don’t quite line up longitudinally…the rear vibration isolators need to drop a bit

Nearly perfect fit.

There’s a 0.003″ gap on the right side of the coupler, but that’s well within tolerance for the DriveSaver. I still have to drill the holes for the vibration isolator bolts and then use the gantry to lift the engine out of the way so I can coat all of the bare aluminum with Devoe 235 epoxy. When I put the engine back in place, I’ll close up that gap. The hard work on this starboard engine install is just about a wrap. It’ll be much easier doing the port side now that I know what to do.

Next up on our 1969 Chris Craft Roamer 46 Refit: Cummins Engine Install — Coating the Stringers & Final Fit

1969 Chris Craft Roamer 46 Refit: Cummins Engine Install –DriveSavers & Spacers

I’m still working on getting the engines installed while the scorching hot summer passes by. Since I’ve never done a complete engine swap before, the learning curve here is pretty steep and my assumptions about many things have been wrong. Fortunately, once I work out the process with the first engine, the second one will be a snap by comparison. 🙂

The basic problem: the top of the inner stringer isn’t parallel with the outer stringer

Rear spacers bonded with epoxy, cabosil, and atomized aluminum powder

Rear spacers ready for final sanding and installation

Epoxy thickened with cabosil and atomized aluminum powder will fill the gap between the stringer and the spacer

Rear spacer leveled side to side and bolted in place

Thickened epoxy has excellent compression characteristics, and its only purpose here is to level the spacer. In addition to being bonded with epoxy to the stringer top and side, I also bolted it through the side. The vibration isolators use 1/2″ bolts that will go all the way through the isolator, the spacer, the stringer, and a 3/8″ backing plate I’ll use on the underside of the stringer when I put it all together. The combination of the epoxy bond and heavy mechanical fasteners should keep everything together nicely and perfectly aligned.

At the front, thickened epoxy clamped to level the stringer top

The 3/4″ plywood scrap in the pic above has a strip of mold release tape attached to it so the epoxy won’t stick to it. The plywood is just wide enough to span the stringer top and land on the piece of 3/8″ aluminum angle that’s epoxy bonded and clamped to the stringer.

Voila!

The top of the inside stringer is now flat and on the same plane as the outside one

Front stringer is ready to test engine fit and shaft alignment

I’ll remove the bolts, sand, and paint this whole area white after I’m done test fitting the engine.

DriveSavers arrived!

The DriverSavers permitt me to move the engine, vibration isolators, and spacers forward enough so the rear vibration isolator bolts will clear the transverse frame under the gear; a problem I described in my last article. That’s one expensive piece of rubber, but it will also lessen vibration and electrically isolate the shaft and prop from the rest of the boat. All told, it’s well worth the price.

Next up on our 1969 Chris Craft Roamer 46 Refit: Cummins Engine Install – Shaft Alignment and Front Engine Mount

1969 Chris Craft Roamer 46 Refit: Cummins Engine Install — Spacers II

In my last article, I wrote about the second step in the process of  installing the Cummins engines into my Roamer. I came up with one plan for engine beds that didn’t work out at all, then cut up one of the beds to make spacers that should work just fine. But then I realized that the top of the stringer on one side isn’t square to the stringer upright, which complicates things just a bit. Just when I thought I’d worked around that problem, another one jumped out to bite me.

Up front, the vibration isolators are totally bottomed out

I even had to remove the locknut (lower left corner of the picture above) to lower the front of the engine far enough.

At the back, 1-1/2″ thick spacers put the engine at the right height

Perfect fit…zero gap at the couplers

But then, I checked the clearance under and around the engine…

There’s less than 1/8″ between the oil pan and one of the frames

There’s also zero clearance between the gear cooler and the top of the stringer. I need to move the engine out of the way and make some space.

Gotta love that gantry!

The gantry is absolutely the best tool I’ve ever made. Moving these one-ton engines around by a couple thousandths or a couple of feet is a one-man job.

Jigsaw makes quick work of the frame

That little wedge I cut out of the aluminum frame to make room for the oil pan will come in very handy in my next article.

Sharpie mark on the stringer marks the line for the fuel cooler

I need to cut the top of the stringer along the line I marked with a Sharpie so the fuel cooler bracket at the top of the pic above will fit between the stringers.  These coolers are notorious for causing installation headaches, and I’m experiencing that personally on my boat. Either way, it’s nothing that a gantry and jigsaw can’t fix.

Just like the front, the inner stringer isn’t square at the back

I’ll square that up the spacer when I finally install it in the next step.

The spacer is looking good…but..oh jeez.

I was so focused on the gear-to-prop shaft coupler gap, and centering the engine between the stringers, and trying to figure out what to do with the front motor mounts that are bottomed out, and the inner stringer that isn’t square to the upright frame that I totally missed the HUGE problem in the pic above.

The prop shaft coupler and gear coupler are perfectly mated, and the propeller is the exact distance it should be from the aft-most strut. But the 1/2″ bolt that will secure the rear vibration isolator to the stringer lands in the middle of the transverse frame behind the gear. That frame is welded to the engine-side of the upright stringer and the piece of aluminum angle in the pic above that forms the top of the stringer. There’s no good way to drill a hole through the stringer that won’t put the bolt and nut in the middle of that upright frame or the weld that holds everything together.

A pic from my last article shows the offending frame–how did I miss THAT???

I can’t move the engine back so the bolts clear the frame, since that would require pushing the prop shaft further out of the boat, which would put the propeller hub 2″ past the aft-most  cutlass bearing. I can’t pull the prop shaft further into the boat, because that would put the prop too close to the aft-most strut. The prop shaft can be shortened, but it’s already machined and installed. I could also have a new set of motor mounts made (which is probably what I should have done from the beginning). All of which reminds me of something I wrote about before: the butterfly effect, and how little tiny things that happened a long time ago can cause ripples in time that wind up kicking me in the balls years down the road.

I was originally going to order the prop shafts after the mechanic installed the engines, so I’d know exactly how long they needed to be. I fired the mechanic after he didn’t get the engines installed for several months back in 2012, but I’d already ordered the prop shafts based on his measurements. If only we had done things per the original plan…

While mulling over what to do about this new problem, I kept working on the spacers.

Epoxy + cabosil + atomized aluminum powder glues spacers together

Shopsmith 12″ sanding disk smooths the bonded aluminum

Nice radii on all sharp spacer corners

Good lookin’ spacer, ready for install

As I was finishing up sanding the spacers, an idea from years before came back to me. I remembered that in my original plan I was going to use DriveSavers to isolate my prop shafts from the gear. DriveSavers are basically industrial strength rubber donuts that isolate prop vibration, provide drivetrain protection in the event of a prop strike, and they break electrical continuity between the hull (via the engine & gear) and the prop shaft and prop, which is even more important on metal boats than on other hull materials. Far more important, though, was that DriveSavers generally require the engine to be moved forward or the prop shaft to be cut by about 1″ to make space for the rubber donut. In my case, they’ll permit me to move the engines forward far enough for those aft-most rear vibration isolator bolts to clear the upright frame, plus provide all of the benefits that originally convinced me they were something I needed on my boat.

We’re back in business…I think.

Next up on our 1969 Chris Craft Roamer 46 Refit: Cummins Engine Install –DriveSavers & Spacers

1969 Chris Craft Roamer 46 Refit: Cummins Engine Install — Spacers

Having finally discovered that the mounts that came with my Cummins engines would not work on the Roamer without modification, I took them to a local machine shop and had some work done. Meanwhile, back in February 2014, I had a fancy schmancy idea for engine beds. Unfortunately, that idea was based on a few assumptions that turned out to be wrong–like, thinking the engine mounts were symmetrical…silly me. Even more unfortunate is that I went ahead and bought a 25′ stick of 3/8″ angle and 1/4″ plate in 6061 aluminum and cut and welded my creation together…proving once again that a fool and his money are soon parted. But on the principle of making lemonade when life hands you lemons, I’m re-purposing the fancy engine beds as spacers between the vibration isolators and engine stringers.

Back from the machine shop, with a longer slot

My uber-precise engine centering gauge

When I first attempted to install the engines, I used a piece of tape between the stringers with a mark at the mid-point. Every time the engine touched the tape, it ripped (surprise!). The tape ended up stretching, too, so it was pretty useless as a center indicator.  So now, I use a piece of aluminum angle with a mark indicating the halfway point between the outside edges of the stringers. I put a square on the angle, line it up with the mark, and then move the front of the engine until the square is centered in the middle of the damper pulley.

The mark at the mid-point between the stringers

The middle of the damper pulley

With the new slot cut, the vibration isolator looks like it will land on the stringer

ShopSmith saw quickly cuts up expensive engine beds into useful pieces

Cutting expensive 3/8″ angle to make plate spacers

On the upside, I’ll have lots of left over aluminum to practice welding on…maybe make a shelf or two

Starting to look like a spacer

Putting an angle on the ends

I need to keep the plate out of the radius, or a gap forms between the plate and the angle

That ought to do it

3/8″ angle + 3/8″ plate = 3/4″ spacer at the front

Reconfigured rear engine mount + 3/8″ angle + 3/8″ plate (x3) = 1-1/2″ spacer

From the beginning, I wrongly assumed that the mounts that came with these engines had the slots at the same elevation. It turns out that was completely wrong–the front mounts are lower. Having never done this sort of thing before, I’m pretty much guessing how many spacers I need. After putting in 3/4″ spacers at the front and 1-/1/2″ at the back, I still had at least an 1/8″ gap at the bottom of the couplers. So I removed the spacers at the front and started dropping the vibration isolator bolts lower and lower to close the gap.

Out with the spacers at the front

In the pic above, you’ll notice that in addition to there being no spacers anymore, I’ve also bottomed out the vibration isolator. See the big nut in the lower left corner of the pic? That’s the locknut that’s supposed to go under the other nut and washer on the under-side of the engine mount. Taking it out allowed me to drop the front of the engine an additional 1/2″ and get the couplers to align. But I think it’s unwise to run without the locknut. Hmmm

Perfect fit…zero gap

And then, another problem that was right in front of me made itself apparent. If you look closely at the left side of the pic below, you’ll notice (as I belatedly did) that the angle of my uber-precise engine centering gauge is hovering above the engine stringer. rather than sitting firmly on it.

Hmmm

The original angle on the stringer is not square

It turns out that Chris Craft welded the 6061 angle to the stringer with the upright stringer plate impeding into the inside radius of the angle. This creates a gap between the angle and the plate and changes the angle between the upright stringer plate and the top of the stringer from 90° to ~95°. So, to avoid inducing stress into the vibration isolators from that 5° misalignment, I need to make a spacer that will level the stringer here. But if I do that, it will raise the front of engine, and there goes the perfect alignment of the couplers!

Dang it! Back to the drawing board!

Next up on our 1969 Chris Craft Roamer 46 Refit: Cummins Engine Install — Spacers II

1969 Chris Craft Roamer 46 Refit: Cummins Engine Installation I

Way back in May 2012, the paperwork snafu that nearly ended this refit project on a very disappointing note was resolved. With the boat indisputably mine, the first thing I did was  buy a set of lightly used Cummins 430hp 6CTA Diamonds with ZF LRM280A gears. The engine installation was supposed to happen in 2012, but Aric Euler/Chesapeake Marine Engineering–the mechanic who said he could do the installation–only showed up to open the engine room hatches, block up the floor a bit, and assemble his gantry. All through the fall and winter of 2012, we were dancing over the open ER hatches and around the gantry waiting for the mechanic to finish the job. Eventually, I had to get the gantry out of the way and close up the ER hatches so we could install the salon roof hatch even though the engines weren’t installed. In the end, I fired the mechanic and decided to DIY the install. Fast forward to 2015, and the gantry I built is ready to go and the blisteringly hot summer making it too hot to work up high in the boat. It’s finally time to get started on the engine installation.

Gantry leg and trolley

Rounded the edges of the I-beam

Ready for the chain hoist

It’s gantry time!

After blocking the floors under the gantry legs, I hooked up the chains and lifted the 2,000lbs engine and gear. Then I rolled it into rough position and placed single 4×4 blocks of wood under the vibration isolators to get a sense of what had to happen to mate the gear to the prop shaft.

No creaking, cracking, or groaning…we’re good to go

I have to say, the gantry worked very well. With it, it’s a one-man job moving this beast of an engine around.

My amateur welds are holding up just fine

Gap at the bottom between the couplers means the front of the engine is too high

This ZF gear comes with a 7 degree down angle. The prop shaft enters the boat at an 8 degree angle. So I anticipated that the engine would be oriented up at the front by roughly 1 degree. What my assumption completely failed to account for was that these engines hadn’t come out of a Chris Craft. Every big Chris Craft boat I’ve owned has had 22-24″ between the engine stringers, and the prop shafts and engines are centered between them. What I eventually realized with the engine mounts on these Cummins engines is that they aren’t symmetrical and they weren’t made for a boat with the prop shaft centered between the stringers. That’s gonna complicate things.

And then there’s the matter of that 5/16″ gap at the bottom of the gear and shaft couplers. The amount I’ll have to drop the front of the engine to close that gap turned out to be surprising.

Front inboard vibration isolator maxed out to the inside but still overhanging the stringer

Aft outboard vibration isolator maxed out to the inside and half-way overhanging the stringer

Inboard gear mount measures 7″ inside to outside

The same pattern repeats with the inboard gear mount, where the vibration isolator can’t go any further toward the engine, but part of it hangs off of the stringer.

Houston, we have a problem

The outboard gear mount measures 9-1/2″ inside to outside…2-1/2″ more than the other side. Ever have a problem that was right in front of you for years, but you never saw it…until one day when you really, really, really didn’t need any more problems?

Yup. It was kinda like that. Seriously deflating. Then again, with the paperwork snafu, the problem with “Mr. Good but slow,” the problems with Chesapeake Marine Engineering, the major theft in 2014 and the resulting problem with the windshield fabricator to replace stolen parts, and (finally) the exploding boat next door last month…I should be used to this stuff by now.

But whatever. Gotta keep moving forward. So I marked the mounts and started thinking about machine shops.

I have to remove some old engine mount material from the stringers

The gantry makes it easy to lift the engines and move them out of the way, which I had to do to get rid of the remaining weldment from the original engine mount boxes that were welded to the boat.

The vibration isolators need to land here, so the weldment all has to go away

A circular saw with a carbide blade makes quick work of removing aluminum welds

I’ll grind the high spots that remain later. For now, I need to get the front and outboard rear engine mounts to a machine shop for modification.

Next up in our 1969 Chris Craft Roamer 46 Refit: Cummins Engine Install — Spacers

 

1969 Chris Craft Roamer 46 Refit: Gantry Time II!

It’s mid-summer in the Mid-Atlantic region, which means it’s hot! And in Tent Model X, it’s hotter still. Up on the deck level, it’s well past 100 degrees by 11am most days. But down in the engine room, two tons worth of Cummins 430hp 6CTA Diamonds are nice and cool, just waiting to be installed.

The original plan was to have the engines installed by a Navy-trained “marine engineer” back in 2012. But the pro kept slipping the schedule until it was 2013. I eventually learned that he was sloppy, incompetent, and that he grossly overcharges for services–sometimes even charging twice for the same service. Other customers of his confirmed similar experiences. So I fired him and, like so many other things, decided to DIY the install. I’d already ordered the propeller shafts based on his calculations, and the vibration isolators, strainers, etc., were all brand new, sitting in boxes…all of which were stolen when the big theft happened back in May 2014. But the insurance company covered that loss (minus depreciation and deductibles), so once again I have all the pieces ready to go. While awaiting settlement from the insurance company, I designed a gantry that I’d use to move these big chunks of metal around. All I had to do was buy the I-beam and tubing and get to welding.

The Gantry Plan

Unfortunately, the SD card that had all of the pix of the gantry build got corrupted, so what follows are the ones I was able to recover.

Gantry top plate and I-beam, drilled and fitted with 1/4-28, Grade 8 bolts

Grind off mill scale in preparation for welding

Tacked the two nuts on the end of the plate, since they will be inside the main upright

Getting low on CO2/argon…but it should be enough

I-beam, top plate, and upright, ready for welding

No, I was not drunk when I laid that wobbly bead

I tacked all of the pipes, the top plates, and the upright sections in place, then put heat to ’em. I’m not a professional welder, and even as an amateur I don’t weld enough to retain the skills I picked up during high school welding class many decades ago. But I was out of position! It was getting dark! Dinner was ready! 😉

Anyway…compared to some farmer welds I’ve seen (to say nothing of home-built trailers!), it should be just fine.

Welding at night, but I got ‘er done…looks just like the plan!

I sure wish I had a welding table, and a bigger garage, and…the list goes on.

Now that the gantry is ready to go, I ordered a gantry trolley and chain hoist from Harbor Freight. I’m ready to move all the heavy steel to the boat and start working on getting those engines in. It’s a good thing that gantry comes apart…that I-beam is heavy!

Next up in our 1969 Chris Craft Roamer 46 Refit: Cummins Engine Installation I

1969 Chris Craft Roamer 46 Refit: Gantry Time

I’ve been having a heck of a time finding a mechanic I can trust. I would have preferred to have somebody come in and install the engines, but the three mechanics who have come out have failed to impress. When competence isn’t the concern, the prevailing attitude seems to be “Meh…it’s an old boat,” and that attitude manifests in the quality of work being done. It’s frustrating.

Anyway, the time has come to move the engines back into their final resting place. I’ll need a gantry to move them, since the Cummins 450 Diamonds with gears weigh about one ton each. I’ve been looking online, but all of the ready-made gantries are too big, too small, too tall, or too beefy to be lifted up onto the boat and then into the salon where the engine hatches are. So, I decided to buy a trolley from Harbor Freight and make my own gantry. I messed around with Google Sketch-up and came up with a structure that can be disassembled into manageable pieces, is just the right size for this application, and will have no problem supporting one ton.

Gantry plan

Gantry leg

It turns out that you can buy the steel (cut-to-size from shapirosupply.com) and trolley, including shipping, for less than half what a Harbor Freight gantry costs. While it will take some time to weld together and drill and tap holes, I’d spend about the same amount of time modifying the HF gantry to work in the boat.

Next up in our 1969 Chris Craft Roamer 46 Refit: Laying Out the Aft Cabin Walls

1969 Chris Craft Roamer 46 Refit: Engine Beds

My priorities for 2014 are 1) propulsion install, 2) steering, and 3) windows, glass and sealing up all exterior openings. On one of the frosty cold Saturdays in January, I went to the boatyard and started measuring the engines and the space they’ll occupy in the engine room. Lemme tell ya–when it’s 18°F outside, the engine room of an unheated aluminum boat is the last place you want to be for very long. Fortunately, it didn’t take long to get the measurements. Before frostbite set in, I had everything I needed and charged back home to play with google SketchUp on the computer.

Your basic virtual Cummins 430 Diamond in a Chris Craft Roamer 46

The vertical stringers are 1/4″ aluminum plate that’s seam welded on both sides to the hull plating. The stringer plates are topped with 2-1/2″ x 3″ x 1/4″ 6061 aluminum angle that is seam welded on both sides to the stringer. The width from the top outside edge of the angle on one side to the other is 28 inches.

Motor mounts land right on top of the OE stringers

And when I say “right on top”… I mean dead-center over the 1/4” aluminum vertical stringer.

Vibration isolator bolts will have nowhere to go

The isolator bolt is 1 inch diameter. If I set it all the way inboard (relative to the engine), the bolts that attach the isolators to the stringer will go directly into the vertical stringer plate, leaving no way to put nuts on them. If I move the isolator outboard, the bolts will go into the angle. If I continue moving the isolator outboard, the bolts eventually hang over the air with only about 1/3 of the isolator perched on the stringer.

I could remove the motor mounts from the engines and have the slots cut further inboard. But if I do that, I’m reducing the width of the footprint. On the principle that the mounts that came with the engines were engineered with a certain size of slot, I decided to maximize the width of the isolators. Which means I have to make new engine beds outboard of the existing stringers.

I’m thinking something like this

5″ x 3″ x 3/8″ 6061 angle with 3/16″ gussets and a 1/4″ bar running along the bottom so the offset matches the OE angle that’s welded to the outside of the vertical stringer.

I like the orbit feature of SketchUp that allows you to view the object from any angle and capture it in a jpg file…and free is a very good price!

While I kind of felt like January and February 2014 were lost months on the refit, it’s not a bad thing to have the time to think through and design stuff like this. I was able to do the same thing during the paperwork SNAFU lull, when I worked out many of the interior concepts for the boat. With the engine bed designs done, I ordered the materials from Posners. By the time the nasty winter weather broke I was ready to start fabricating.

Dry fitting all of the pieces

I used my Harbor Freight handheld bandsaw to cut the 25′ stick of angle into four pieces and my Shopsmith bandsaw to cut the gussets. Then I used the 12″ sanding disk attachment to square up all of the parts and leave a nice finish.

Not a bad fit

I will hold off on welding it all together until I’ve got the prop shafts in so I’ll know where the engines will sit. This is one of several welding operations that will happen one day in the next few weeks.

Next up on our 1969 Chris Craft Roamer 46 Refit: Return of the Bow Seat Windows