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Engine, Saildrive, and Fuel System Upgrades
Last Updated: 11/30/2017

Engine Parts Supplier Links

Engine Oil Analysis

Jackmaster Oil Filter
Saildrive Oil Header Tanks Saildrive Seals
Keeping Your Fuel Clean Engine Parts Manuals
Digital Laser Photo Tachometer  

Propeller Choices

We had a fixed prop on our CSY 44 Monohull, and I was convinced that was the correct choice at the time.  You can read my thoughts from 2008 about fixed vs folding vs feathering props here.

Our catamaran came with a pair of two-bladed aluminum props.  But there was no spare prop included, and the originals looked pretty worn out.  We really needed a new pair of props.

There are quite a few feathering/folding props to choose from. There's no question that a feathering prop is the best choice for pure sailing. I believe they will give you almost 3/4 knot speed boost, not having to drag that big prop while sailing. The down side is the huge difference in cost.

The Original St. Francis 44 Prop

Original Prop Original Prop

A friend was enthusiastic about Kiwi Props, made out of a lightweight composite material.  So instead of buying a spare aluminum prop, I bought a pair of Kiwi Props.  They cost $1500 USD each, delivered to Florida, and come with spare blades.

  kiwi prop feathered
kiwi prop
Kiwi Prop Exploded

I do believe they have increased our speed under sail.  But the composite blades are not bulletproof.  We have already broken one blade by running into a heavy semi-submerged piece of wood.  However, it was an easy matter to fit a new spare blade, which we did by just pulling into a shallow sandy spot and doing the replacement in the water.

After the first year of use, in which we had no problems, we had a little trouble this year going into reverse.  We carefully inspected the props several times for growth, but could not find anything externally on the props that would cause a problem.

Now that the boat is hauled out for maintenance, we have not taken the time to try to track down what the problem is--a transmission issue or a propeller issue.

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Coming Soon: Saildrive Gear Oil Header Tanks

Coming Soon: Saildrive Seals

Synthetic Oil & Engine Oil Analysis

I use a lab in Atlanta called Power Trac to do my engine oil analysis (800-394-3669), but there are many others. Just stop by any large diesel dealer and they can sell you a sampling kit consisting of small double plastic bottles for about $12 US.

I take a sample about every 300 hours and send it in via any cruiser going back to the US. After a week or so they will send me the detailed computer printed results via mail, fax or my phone call. It's a great way to keep tabs on what's going on inside the engine.

Most major truck fleets and other multiple diesel users like the US Navy have been doing this for years. Oil analysis is part of what we called trend analysis in the Navy, and it was part of the engineer's work to monitor it.

In order to extend your time between oil changes, use synthetic oil, make sure you get a bypass oil filter to remove contaminants down to 1/2 micron and all moisture from the oil. Otherwise even though your synthetic oil's lubricity may be intact, and it should be for a couple of thousand hours, the oil will get overwhelmed by contaminants and water. My synthetic oil of choice is Amsoil.

In addition to the synthetic oil being better for your engine, the main reason I started using synthetic oil was to keep from having to carry the many gallons of oil I would need to change oil every 150 hours as engine manufacturers recommend. Third world oil is of questionable quality and very expensive.

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Jackmaster Oil Bypass Filters

On the Perkins engine on the CSY, I used an Amsoil Bypass Filter that required relatively expensive filters.  (Amsoil Discussion)

On the new boat, I have fitted Jackmaster Oil Bypass Filters.  They use toilet paper rolls as their filter medium.  Jackmaster Filters

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Keeping Your Fuel Clean

It is a good idea to thoroughly clean the inside of your fuel tanks by hand rag about every 5 years. So far I have seen no way to do this on our catamaran!  The fuel tanks are permanently mounted in a locked with no access port.

But so far we have had no fuel problems.  We use a modern plastic housing filter, similar to what West Marine sells, to filter ALL fuel coming into the tank. These have been tested to be better than the old and expensive Baja filters.

Filtering your fuel as you add it to the tank is the only way to make sure you are getting clean fuel and won't end up with contaminated fuel at the bottom of the tank.

We also use the Hammond Biobor and Lubribore products to clean and lubricate the fuel.  These products only require a small amount to be added to every tank full of fuel, so a couple of quarts goes a long way.

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Recommended Reading:  Diesel Repair Manuals

(Topica Post 2004) Regarding good diesel manuals and obtaining advice I would recommend obtaining a copy of one of Nigel Calder's books: Marine Diesel Engines or Boat Owner's Mechanical and Electrical Manual. Look in There are also others.

You should also have onboard both the Owners Manaul, the Parts Manual, and the Service Manual for your engine.

It's well worth doing your homework by reading these manuals and learning your engine before something goes wrong and you end up spending a great deal of money for someone else to fix it. Armed with the knowledge from these sources you will also be better able to seek and evaluate any advice you may obtain--including the above. 

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