Replacing the Engine's Heat Exchanger

Typical Boat Project Creep - Leaking Heat Exchanger

During a routine engine inspection, we noticed a bit of coolant leak and I suspected it was coming from the Coolant Reservoir overflow due to an aged Pressure cap. After cleaning up the closed bilge under the engine and placing a puppy pad to detect any coolant leak with the engine off for a week or two, I felt confident that it was a leaky pressure cap. WRONG !! When I checked today the puppy pad was soaked with engine coolant. Clean Coolant!  It has to be leaking from a hose, hose connection or the Heat Exchanger. There's no visible source of the leak and it's pretty minimal but a leak is a leak!  Plus side? We now have a new Radiator Pressure Cap. 

The heat exchanger is showing it's age. Last serviced 4 years ago, but showing some corrosion by the Raw (Salt ) water hoses and the Coolant hoses. But the hoses connecting to the Reservoir and their connections seem to be good, those hoses are probably original.

Decision made - it's time! I ordered a replacement heat exchanger from Mr Cool online.$560 inc. Tax & Shipping ( UPS Ground )

It arrived Thursday ( 4/16 ) and it looks as good as the photo. 

I decided to replace the coolant hose with Silicone Radiator hoses, they are on their way but won't arrive till April 24th ( Amazon ), so I'll hang back on the heat exchanger till next week. Got plenty to do in the meanwhile. 

Hose arrived, they look really good, bright Blue!

We'll replace the Heat Exchanger and the coolant hoses next week ( 1st week of May). 

I'll try to pump out the coolant using a small hand pump we keep on the boat. Any that leak will go into the Engine bilge which is blocked off from the boat bilges. That will avert any coolant being pumped overboard.

Can you feel the Creeping Project Syndrome kicking in yet?

Sometimes I should spend a while longer inspecting things that I'm going to replace.

While swapping out the Heat Exchanger, I realized that the 39 year old hoses from the Heat Exchanger to the Reservoir are looking their age and when I tried to remove that hose, it was obvious that now is time to replace the entire hose line from the heat exchanger to the coolant pump.

Right now it's a Heath Robinson setup.

There's a traditional ( OEM ) hose from the heat exchanger to a Metal Elbow connector, that connects to a rubber hose about 2" long, that's connected to a brass Elbow and then via another piece of rubber hose, which appears to have several wraps of tape beneath the hose clamp, and finally to the Coolant pump connection.  All of those connections are made with the old type perforated hose clamps.

So, here's the parts that will be installed as soon as they arrive, that's a week later.

This is the 7/8" ID Silicone Radiator Hose.

Connection to the next item:----

These are the 304 Stainless Steel Connectors to join the pieces of hose and navigate around the corner of the engine and the Alternator

I'll not be using the clamps which come with the barbed connectors. T

This is the same hose material but is molded for a 90º turn to get around the corner of the engine and Alternator

I'm using another of the Stainless Steel Connectors to connect to the next bit.

This is the 90º molded turn with expansion to 1" ID for connection to the Coolant pump.

Schematic of Coolant Hose Connections

All of the pieces have arrived. Plan is to do the upgrade on Sunday - should finish it before lunch, but it is a boat project and we all know how they have a habit of creeping :)

Before:

This is how the engine looked in 2020, several things have changed, New design alternator support arm, New drive belt and pulleys, some of the hoses have been replaced with Blue Silicone.

It's time to service the Oberdorfer Raw Water Pump but that can wait a few days. I have a spare.

We have an upgrade for the Oil Filter but that's not high on the Boat Priority list.

Ok, back to the Heat Exchanger and Hoses upgrade.

Here's the 1st part of the new hose setup.

The 1" to 7/8" 90º Silicone reduction elbow hose is connected to the Coolant Pump ( Top left of image ) 

Next is a 7/8" - 7/8" Stainless Steel Connector ( inside the hose joint :) ) 

Then the 7/8" to 7/8" 90º elbow.

I secured that 90º elbow with a large Zip Tie to reduce any risk of chafing of the hose against the Alternator support arm.

The 90º elbow is connected with another 7/8" to 7/8" coupler onto a flexible 7/8" Silicone hose.

Tried my best to route that hose so that it does not chafe against any of the wiring or the Starter Solenoid.

That flexible Silicone hose connects to the Heat Exchanger ( the connection is below the Heat Exchanger and nearly impossible to photograph from on top of the engine.

That completes the hose upgrade and install of the new Heat Exchanger.

Next - Test for leaks and eliminate air in the system.

But first! Refill the coolant system.

It took most of this bottle of coolant. That's 3.78L 

After filling the reservoir I opened the Raw Water thru hull and started the engine. As soon as we confirmed that the exhaust was blowing out water, I raised the RPM to 2000. Then just waited to see if the engine temperature rose above 150ºF, our normal operating temperature.

It did! When it climbed to 175ºF I shut down the engine and let it cool for 20 minutes while I worked on another project. Before restarting the engine, I added a little more coolant to the Reservoir and then Ran it again, but this time running the engine at WOT. The engine temp gauge showed 160ºF at this start but soon went down to our normal 150ºF. I left the engine running for another 5 minutes and it stayed in the golden zone.

Consider this project done! 

I cleaned up the coolant that had flowed out of the overflow pipe and dried the engine bilge. Just a check for when we go back to the boat in a few days.

With the project done, I closed the Raw Water valve and tided up a little. Next time we're at the boat, I'll store all the tools and make the cabin liveable again. I did find some corrosion on the bear box bleed screw, so I'll take a wire brush to that and put on some protective coating on it. Probably a zinc spray.

Ok, update the service history and move on to the next job.

See you on the water, probably next week.

Paul

Installing New Solar Panels pt. 2

Installing New Solar Panels 2026 Pt. 2

Ok, I think I have everything but don't hold your breath. 

Saturday, we mounted two beams of 4040 Aluminum Extrusion ( made from 2 1m pieces, so 2 meters long )  They were secured to the Bimini Frame at the four corners using 1/2" AL Spacers and 3 1/2" M6 Bolts that threaded through the Bimini tube hinge fittings.

That all went well, but, because of the position of the Backstay Bridle, I had move the aft solar panel a little further that means the beams will need extending by about 6" I have the bits to do that.

To attach the Solar Panels to the Beams, I ordered

Once cut to length, they can be connected into the rectangular frame and mounted on the boat over the top of the Bimini.

These will be attached to the Beams using the T Nuts and the M8 Bolts then they will be bolted to the sides of the Solar Panels with nuts and bolts.

So far this has turned out better than I thought. It looks good, is pretty simple and very sturdy. I did run the Inverter once the panel was connected and turned on the Water Heater, that's about an 1,800w load. The panel output ramped up to 295Watts! From a 320w panel that's pretty good.

Next to extend the beams and mount the 2nd panel for a total of 640Watts of Solar power. The two panels will be in series which should give about 40+ Volts and 24Amps well within the 100v / 50Amp Victron MPPT Solar controller.

Should have some pics of the setup this week. Later I'll move the wiring to inside of a conduit and eliminate the UV damaged cable clamshell on the outside of the coaming.

Well that went really well.

Turns out the simple method was enough.

There was a Aluminum tube that braced the Radar pole to the old Backstay bridle that was just above where the panels are now. I never liked that setup. But I can mount another piece of the 4040 from the Port side mounting frame to the pole and will improve the stability of the Radar. I'll take pics of that too.

Meanwhile, another job to cross off the list.

Sailing plans are for a week Monday down to Biscayne Bay.

See you there.

New Bimini for our Catalina 34

Replacing the Bimini 2026

The new Standing rigging backstays requires two holes in the Bimini wider apart than the original large hole ( 6" Square ) and it was just not feasible to 'modify' the old canvas, besides it has so many patches that we often referred to it as Joe's Coat.

Over the past few years I have made several Bimini's and Dodgers as well as a bunch of other Canvas works that help fund my addiction - Off Center Harbor Disorder. So it was an easy decision to make a new Canvas Bimini. 

My plan was to just make a new version of the old one with a few tweaks.

Unusually, I decided to treat this as a client's project and keep track of the cost and the time. Typically, I charge around $2000 for a Bimini plus materials. It can be a lot less but rarely more.

So far I have over $1200 in hours and materials.

Once of my clients asked about the materials that I use. Almost always, I use Sunbrella for outside canvas, but use other materials for edge grips and inside liners. The thread that I love is Sailrite's Lifetime PTFE TEX 92 thread, it's not cheap: $160 for 8oz. But the thread is really good, it's hard to cut with a hot knife. I have my Sailrite LSZ 1 ZigZag - Straight stich machine tuned up to use that thread. That took a while to achieve, so now no other thread is allowed in my workshop.

So far I have about 18 hours of labor into the project, so it's getting close to my best priced Biminis.

Time for some pics but I got carried away with the test fit and markup for the new Solar mounting frame.

However, I'm really pleased with the outcome. 

To do: 

• Apply reinforcement patches where the Solar mounts attach.  (DONE)
• Extend the port forward snap flap ( it's 2" too short ) (DONE)
• Expand the backstay holes slightly ( the canvas is stretched where the backstay bridle passes through the canvas and leather reinforcements. (DONE)
• Fix missed stitches on Binding port aft snap flap. (DONE)

Then back to the boat for the final fit and mount the solar frame.

2nd fitting today. Now I'm getting picky! ( or trying to be more of a craftsman )

I'm not liking the finish of the lower edges of the snap flaps, so I'm going to clean them up and rework the binding of those short pieces.  But the rest of it is good.

While there at the boat, I reviewed the Bridge Piece and the old piece will not fit, oh how sad, I'll have to replace it with a new bridge piece, I'm actually looking forward to that.

OK. One more day of fixes then it's finally back on and all done.

Bimini Done.

I tidied up the corner flaps that have the sockets to snap onto the studs that are on the SS Frame.

Tension looks good. I'll probably enlarge the two holes for the backstay bridle and put small covers over the holes to help keep rain out.

Turned out nice. There are zippers on all for edges. The forward ones are for the bridge piece - coming soon - and the sides and aft edge zippers are for a full enclosure.

Of course, it makes the dodger top look old! But !!! I'm going to get that done pretty soon.

This moves us closer to being able to get the boat out for a few days - now, if only the Hillsboro Inlet was open for us :(   Right now it has severe shoaling and we could not get out. It's nearly 3' depth at low tide and not enough tide to let our 6' draft clear the bottom.  So our trips will have to be via the Port Everglades inlet for a while until the Hillsboro Inlet District Dredge is able to get back on top of the shoaling. Weather is not cooperating in that objective.

But we will see you on the water soon - just have to replace the Engine Heat Exchanger.

Paul

Caring for Strataglass

How to care for Strataglass Vinyl Window Material used on Sailboat Dodgers and Enclosures

I get asked a lot about this issue, what is the best way to take care of Strataglass Vinyl material that is subject to the UV damage that occurs outdoors in South Florida.

It's a good question. I have seen dodger material that is so damaged that I could put my fist through the material. It's Crispy, Brown, Dry and almost completely opaque after just a few years from installation. When I asked the owner what they had used to keep it clean, the reply was Dishwashing Soap. Others had used Pledge type waxing products.

Why not use those domestic cleaners / polishers?

Simple! They remove the plasticizers from the surface of the Vinyl. Now just to be clear, the plasticizers are removed by UV rays, good old South Florida Sunshine. As those plasticizers degrade, so does the surface of the vinyl and the transparency. The vinyl become ridged and opaque, almost impossible to clean, they turn brown as they prematurely age. This can happen in just a couple of years here in SoFla. 

The answer is to protect your Strataglass and other brands often referred to as Isinglass.

When I purchase Strataglass, normally #40 gauge,  it comes in a 5 sheet container and that container includes mulitple warranty registration documents for the material.

Proper maintenance of Strataglass is essential not only for clarity but also to keep the manufacturer's warranty in effect. The recommended care routine relies heavily on products from the IMAR line.

Routine Maintenance Schedule

Frequency	Action	Procedure
After Every Use	Rinse	Thoroughly flush vinyl surfaces with clean, fresh water to remove salt and abrasives. Air dry or use a high-quality chamois or microfiber towel.
Every 1–2 Weeks	Clean	Use Strataglass Protective Cleaner. Spray directly on the surface or a soft cloth and wipe gently.
Every 1–2 Months	Polish	Apply Strataglass Protective Polish. Use small circular motions with a soft cloth, let dry briefly, then buff to a shine.

Best Practices for Longevity

• Immediate Spot Cleaning: Keep a bottle of protective cleaner on board. If sunscreen, insect repellent (DEET), or other chemicals touch the vinyl, clean them off immediately to prevent permanent clouding.

• New Enclosure Care: New vinyl is soft and "impressionable." Keep panels installed and fastened as much as possible to help them stabilize. If you must stack them, place a soft fabric (like a bed sheet) between each panel.

• Temperature Awareness: Avoid rolling up vinyl when the temperature is below 15°C (60°F), as the material can become brittle and crack. Ideally, only roll them when it is above 21°C (70°F).

• Storage: Never store panels wet. If they develop clouding from moisture, exposure to sunlight or a hair dryer (used cautiously) can usually clear it.

Critical "Never" List

Using the following products will damage the vinyl coating and void your warranty:

• Harsh Cleaners: Never use Windex, Rain-X, Pledge, Plexus, Simple Green, or Orpine.

• Waxes: Avoid car wax or "wash and wax" combo products.

• Commercial Products: Do not use cleaners or scratch removers designed for standard commercial-grade vinyl or plastics.

Note: For the best results, ensure your hands are free of sunscreen before handling the panels, as the oils can cause permanent marks that are nearly impossible to buff out.

That pretty well covers the best practices for keeping your Strataglass vinyl windows clean and clear, however I go a step further. COVER the windows.

I recommend that all Strataglass vinyl windows are covered when the boat is at the dock.  The covers should be UV resistant, and should have a soft material where the covers touch the vinyl. It's best if the covers are attached along their top edge with a material flap that covers a zipper the full width of the window. This reduces the risk of rain drizzling down the inside of the covers and any rain borne chemicals leaving a streak on the Strataglass.  When I make the covers, I use that method of securing the top edge of the cover and Twist Lock Fasteners along the lower edge. If needed, I'll use additional Twist Lock fasteners along the vertical sides of the covers. 

Now, when I get asked " What's the best way to protect my vinyl windows " I'll just say - it's complex but read my blog.

Thank you.

I hope this all helps. 

May your vinyl's stay bright and clear.

Paul

Upgrading the Boom Vang on our Catalina 34

It was past time to fix the Vang

The Boom Vang on Eximius was probably 39 years old. We had replaced the line just recently ( months ) but it was still virtually impossible to make an adjustment other than completely releasing the tension or increasing the tension in significant jumps, ie. no subtle adjustments possible.  Yes, I lubricated the blocks but that barely made a difference.  So! Time for a new Vang.

Catalina Direct sells the replacement kit, just a couple of blocks and some line. 

It's a simple piece of rigging but what a difference! It's now easy to adjust but I did find a method of rigging a cascade pull to make the adjustment even easier! We'll see how that goes later in the season.

Meanwhile, it's time to get some canvas done and the new solar panels installed.

See you on the water.

Paul

Final fix of the Propane System

Fixed - Propane system is now working - correctly

We left the project alone for a few months, we were not planning on using it and other things snuck up on us demanding attention.  So it floated to the top of the ToDo list.

The problem:

After replacing the propane connectors, pressure gauge, regulator and Solenoid, the system was not working as expected. The solenoid was not shutting off the gas flow and pressure gauge was showing zero.

I purchased replacement gauge and solenoid but life happened, so the bit sat on the boat waiting on calmer weather.  That happened this week!

It turns out that the issue was with the new setup. The solenoid was before the regulator and the pressure gauge was on the low pressure side of the regulator - that just didn't work.

I took it all apart and rebuilt it. Now the Supply tank is connected to the top of the stack and the output of the stack is at the bottom.

With it this way, the Pressure gauge reads the pressure of the supply tank: That now works.

The Solenoid controls the flow from the output of the regulator: That work now too!

With the control system setup this way, the Pressure Gauge reads the Tank Pressure ( never worked until now.), the Solenoid controls the propane delivery almost instantly, if the stove is on and then the Solenoid switch is opened, the gas pressure drops immediately and the flame is extinguished.  

The tank valve is normally closed until we need to light the cooker, so we turn off the gas controls on the cooker, turn off the solenoid and then turn off the tank control valve is we do not anticipate needing it again within an hour or two.

It's such a relief having the system working. Not because we use the propane system often, but knowing that it's working and the gas is shut off is a big stress reliever.

Cross that one off the list.

Installing New Solar Panels

 Another Solar Panel Upgrade

As mentioned in my article about replacing our Standing Rigging, I have to alter the Solar Panel install on Eximius.

Currently, we have 600W of Bougrv Solar Panels mounted on top of the Bimini laid out with the single panel athwartships in front of the Backstay bridle and two panels on either side of the backstay bridle. 

Because the new standing rigging's Backstay bridle extends higher from the Bimini, I need to change the panel layout and that involves replacing the 3 existing panels.

The new layout will be as shown below.

The gap between the panels is due to the angle of the Backstay Bridle as can be seen in the lower image.

The panel dimensions are slightly larger than the area taken up by the old panels, I figured that out after completing the previous upgrade.

It looks like I'll be able to install a pair of approximately 435Watt panels giving a total of 870Watts of Solar Power. I know, that's not going to happen, but it should be much better than the Max 0f 600Watts we have presently. I would expect to get at least 700 watts. when the batteries need it.

The panels I'm looking at - next day delivery by Amazon, are about $540 for the pair. 

STAR 870 Watt Solar Panel, 2PCS 435W 48V/24V Solar Panels. 

Update: Because those panels would hang off of the stern by way too much, it would be easy to damage them when docking. So I selected these instead:

Renogy Solar Panels 2PCS 320 Watt Solar Panel 18BB N-Type Solar Panel 12 24 Volts Monocrystalline On/Off Grid Solar Setup 640W Over 400 Watt Solar Panels 25% Cell Efficiency for Homes Rooftop RV Boat They are $599 for the pair. :(

From the specs of those panels, if connected in Parallel, the max output would be around 36v and 50amps. Well within the range of my Victron 100/50amp controller.

But if connected in series, the output would be more like 72v at 30amps and that's a better case for the MPPT controller.

For the wiring, I could keep the existing wiring from the panels to the controller, however, those wires are only 6awg and were only installed 3 years ago, they have suffered UV damage, so I'll replace them but with larger cables, 4 awg and I'll run those inside plastic conduit. Basically, I'll install a connector box beneath the solar panels with a terminal block inside, then wire inside of conduit down to the deck and into the side of the combing and to the area where all of the Victron equipment is located beneath the Nav Table. 

Doing that should minimize the voltage drop between the panels and the controller.

Ok, that's the plan. Now I have to decide "Do I repair or replace the Bimini" before installing the new solar panels.

Now, I do have to comment on the whole issue of Solar Panel sizing and installation. From my experience over the past 11 years of boat ownership, I conclude that it's best to go big!  I have purchased 2 Victron MPPT solar controllers a 100v/20amp and 100v/50amp. I should have purchased a 100v/70amp controller or two 100v/50amp controllers.

OK, back to the design of the Solar Panel mounting.

I like the idea of using 4040 Aluminum Extrusion, and wondered if Google Gemini could come up with a plan. Here's what I asked Gemini:-

design a solar panel mounting frame that attaches to a 1inch tubular Bimini frame using 4040 aluminum extrusions

( The text of  the response is at the end of this post ) Here's the result: I made up this image using the suggested plan for the mounting frame. ( I use Google workspace drawing for most of my diagrams. )

Mounting Frame Connection to Bimini Frame

Solar Panel Attachment to Mounting Frame

Frame Construction.

Basically, using a Stainless Steel Hinged Bimini Rail Clamp on the Bimini Rail, use a couple of Nylon Ferrules as a stand off to allow the stainless bolt to pass through the Bimini Canvas and hold the whole thing together with a M8 T-Nut and bolt.

Gemini suggested I make a rectangular 4 sided frame using the 4040 Aluminum Extrusion, joining the Corners using Inside Corner Brackets.

This should result in a nice looking and substantially rigid frame on which to mount the two panels. I could put rubber washers between the Extrusion and the Hinge Clamp to add a bit of wiggle but I think I'll see how it comes out first.

Parts list

2 x 4 Pack of 4040 48 Inch Black Anodized Aluminum Extrusions

8 x Spartan Power Black Solar Panel Z Bracket Mount

8 Straight Line Connector Joint Brackets ( to join the 48" extrusions )

4 Stainless Hinged Clamps

4 x 2.5" M8 T-Nuts & Bolts

8 Nylon Ferrules ( 1/2" OD 1/4" ID)

4 Aluminium 2" Spacers

I feel that this is coming together nicely. I'll go down to the boat on Monday and double check the dimensions of the panels and frame.

With that, I'll end this post, but here's a link to the Gemini response.  

Stay tuned for the next phase.

Meanwhile, I hope to see you on the water.

Paul