CD36 engine mounts

[Jeff Peterson]

Hi all
Our 1983 36 Perkins 4108 is on the original mounts that bolt to an I-frame steel base that bolts to the hull. The I-frame base is rusting a bit, mostly on the port side under the raw water pump, as is the 1 inch square hollow bar that runs horizontal between the 2 forward mounts. The bar right under the water pump shows the most rust but still seems solid. It has been like this for years, but the yard is under new ownership and the tech mentioned it to the service manager this fall. While new frame would be nice there other priorities and I wonder if anyone has advice on what to look for and when to consider this a must do project? Or, is there a responsible repair that does not require pulling the engine and replacing the frame all around? Thanks

[John Ring]

Hi Jeff,
I replaced the whole engine foundation on my '85 CD36, and it was a beast of a job. My foundation wasn't bolted, just glassed directly onto the hull. I had to remove the Perkins & cut the frame away from the hull with a Dremel and their #543 bit. My foundation was rusted paper thin on the aft starboard corner and threatening to drop the motor at any moment. I replaced it with an identical fabrication made from 316ss and tabbed it in.

First order of business is to stop the leak(s) that cause the rust. If your rust is up front and manageable you may have some options. Maybe give it a few whacks with a hammer & see how solid it sounds. If good, maybe just clean and protect the steel? If it deforms under hammer blows, possibly cut away bad sections and drill/bolt in a new section? Maybe get a welder involved to weld in a new section if it's not too close to the hull?
John Ring
CD36 Tiara

[Jeff Peterson]

Thanks, very helpful

Still working with the yard to sort this out.

[Matt Cawthorne]

My 1982 CD 36 had a wet engine compartment that the previous owner did not fix. I did find the leaks, but the engine mounts were a worry to me. They were a little rusty and I worried what was under the fiberglass. In 2015 the oil leaks finally irritated me enough to go for a rebuild. After the engine was out I did a little investigation with a grinder to see what was under the fiberglass. This is the first thing that I saw

20160116_121922.jpg

. Before I went further, I made a manufacturing jig that 'registered' the key points for the mounting attachments. After finishing grinding away the fiberglass I turned the mount and jig upside down and took this picture. \

20160117_180640.jpg

I am not sure what was holding the engine in place except for the prop shaft. and the slightly less rusted mounts on the other side. Needless to say, you cannot wait for the fiberglass to bulge up to show problems. Whenever steel is covered up with, say, fiberglass and the fiberglass edge is loose, or corrosion is adjacent to the fiberglass the environment is prone to corrosion. Stainless steel is prone to crevice corrosion. Good luck.

Matt

[gonesail]

you gotta wonder exactly what the builder was thinking.

[John Stone]

you gotta wonder exactly what the builder was thinking.

It's all fixable. How much it costs and how well it's done often comes down to how involved the owner is in the repair. I am always for DIY by a patient determined owner wanting the best possible outcome over a boatyard solution any day. But I recognize it's not a reasonable option for everyone.

Over the years I have thought a lot about the use of steel in our much loved boats. The CDs were well built. There are a lot of CDs out there still sailing. Generally, they have held up very well. Some of the boats are closing in on 60 years old. Many are still being sailed without major structural repairs, not that they wouldn't benefit from such projects.

Not many houses can withstand the abuse that sailboats take without major problems. So while problems and repairs to fix them are to be expected it is still vexing when we are on the receiving end.

There kinds of steel boats out there. Sailboats, powerboats, tugs, towboats, shrimpers and commercial fish boats, merchant ships, and war ships. So steel is certainly a marine metal. It would not have been my choice though. And those of us who have had to cut rusted steel out of our fiberglass boats have strong feelings about it. Some of the steel components I have seen removed by others like Matt's engine bed are in horrible condition.

My steel bowsprit reinforcement plate appeared to be heavily rusted but after I cut it out it wasn't in bad shape. I honestly don't remember what condition the engine bed was in when I cut it out. The 'thwartship steel beam the pillow-block bearing is bolted to (it supports the upper end of the rudder post) had some rust (and some pitting) on it but was otherwise in good shape. I cleaned it up, applied an epoxy primer, painted it and reinstalled it. The steel reinforcement backing plates for the chainplates were in excellent shape so I left them alone.

We have all seen a wide range of problems with lousy fiberglass, composite, and aluminum construction so there is no golden solution. And cost is always a factor at some point.

When I finally installed an engine I certainly never considered steel.

I am not sure it was a terrible choice to use steel but I wish I knew how that decision went down. What was that conversation like? Were other options considered and why were they not chosen? Was it purely cost or were other factors at play?

End the end though I would suggest the most significant contribution to degradation of interior components is not the material used to make them but the incursion of water (salt or fresh) into interior spaces. Stopping leaks and achieving a dry boat is the single most important thing we can do to the improve the longevity of our boats and systems.

[Jim Walsh]

I’m with John on this. It would be interesting to know exactly what the logic was to choose mild steel over readily available durable materials. Cape Dory’s were quite expensive for their time so it’s hard to imagine cost was the leading factor when the decision was made.
My CD 31 has a single piece of aluminum flat bar stock which functions as the backing plate for the chainplates on either side. I can access it throughout its full length so I take a peek at it once a year in the spring. Were it mild steel I would have removed it and replaced it years ago. Several years ago I had to remove a stanchion base that was leaking, that also had aluminum backing plates. They were in fine shape so I just replaced the fasteners and reused the backing plates.

[John Ring]

Mine looked like this, and the new one H&H Prop in Salem MA made for me in 316ss, fit like a glove.
John Ring
CD36 Tiara

CD36 bed rust.jpg

New stainless Bed.jpg

[John Stone]

Nicely done John Ring.

[John Stone]

Just for fun I attached a couple pictures of our engine beds on the Far Reach. One thing I recommend, if you're going to have a frame built, is considering adding a slide out removable drip pan. It might not fit in that system and if not perhaps a molded tray underneath to catch any drips of oil or water coming off the rudder post stuffing box or shaft stuffing box. Any issues there and you'll see the evidence with out it being lost into the bilge. You can wipe it up with paper towel. Maybe add a removable plug in the forward face to allow water to pass through if you are washing out the lazarette or cockpit lockers.

[John Ring]

Wow, super clean installation John. Love the cookie tray!
John Ring
CD36 Tiara