Removing Pedestal Screws - Lessons Learned

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Jan 27, 2008
3,092
ODay 35 Beaufort, NC
Had to replace my engine control cables late last week. Steering system is a classic Edson pedestal with a Ritchie compass. Compass came off fine and then immediately my project turned into another project. The four screws holding the compass mounting plate and control housing to the pedestal wouldn't budge. These are 1/4 - 20 x 3.5 inch long slotted head stainless screws installed into an aluminum pedestal. Never apart in 28 years so they were seized badly.

Maine Sail recommended an electric impact driver so I figured I'd give it a try. Also PB Blaster was recommended. I soaked the screws for hours with PB Blaster. With a very large screwdriver I was finally able to get one screw to break loose and removed it. Still have bruises on my hand from the screwdriver handle digging in trying to turn it so hard. All the others I tried the impact driver but the first lesson was a slotted head screw is basically impossible to control the bit from sliding out from the impact driver. Too much risk of damage to surrounding parts to make this work. If the screws were Phillips head or hex head this might have worked.

I used a dremel (Black and Decker equivalent) with cut off discs to cut off the heads of the screws. Once the heads were gone the compass mount and control housing came off easily. Now I had three very long studs sticking up and frozen in the pedestal base. So the next recommendation was to use vice grips on the studs, another lesson it didn't really work well. The screws are so small in diameter that it was hard to get the vice grips to get a good bite on the screws, you have to use the very end jaw of the vice grips and they didn't hold well enough to turn the stud. Continued soaking with PB blaster throughout the day while attempting multiple removal techniques. I finally settled on using a small size pipe wrench. While also hard to get a good bite on the small screw I was finally able to get a second screw to turn a little, it was hard to tell if the screw was just twisting before breaking or actually turning in the hole, but I was prepared to drill and tap if needed. Working the screw back and forth a few times to break it free seemed to help, I finally freed it enough that I knew it was unscrewing and was able to remove it finally.

Turning my attention to the other two remaining studs I continued with PB Blaster and using the pipe wrench and for each one I was able to eventually break it loose, I tried a larger pipe wrench but was not able to get it to bite into the screws. In each case I was sure the screw would twist off and break but in each case it finally unscrewed. So after getting them all out I used some never seize on the threads of a good screw and worked it in and out of each hole until the threads turned freely by hand, running a tap down the holes would be another good practice to clean up the threads.

Pulling out the cables and cable clamp turned into another task, the clamp would not fit with the chain in the way on the sprocket, so into the rear propane locker to remove the vent hose and plastic liner, then into the quadrant to back off the tensioning screws for the steering cables. Maine Sail recommends nylon lock nuts but I had jam nuts on mine, so I will need to add lock nuts at a later date. You can always just thread a lock nut on top of the two jam nuts. Now with the chain out of the way I was able to get the clamp and cables pulled up enough for removal.

On reassembly instead of slotted head screws I went to the hardware store and purchased four hex head screws and four Phillips head screws ( I wasn't sure if the hex head would fit without interference so the extra four bucks would save me a trip back again. They also had nylon washers to put under the heads as I found in the original installation.

Edson sells "special coated" screws for 27 bucks for four of them to prevent the galvanic corrosion since they learned over the years I guess. I am guessing the coating is dry film lubricant, also known as electrofilm but am not sure, that is a very high price for four screws. The stainless screws I bought uncoated were about 1.20 each or call it 5 bucks for four. The hex head bolts went in perfectly with no interference making me wonder why Edson didn't use them in the first place? A socket wrench provides a much easier installation and removal method with far less chance of stripping the head. I coated the threads very liberally with Permaloc Never Seize compound (available at auto part stores). It looks just like what we used to refer to in aerospace as "silver goop." With all parts reassembled and the steering cables retightened all systems appear ready to go.

My final task was to rebed the screws in the base, Edson now uses hex head bolts for the base but mine are slotted head screws in countersunk holes. The nuts underneath were barely finger tight and one was pretty loose but removing the screws with the bedding compound on them was still tough. I tapped them with a hammer from below using the nut on the bolt to prevent damage to the threads on the end of the bolt. That worked well and then using the screwdriver to loosen them up for the last small amount of length. I then spent a copious amount of time cleaning the bolts and holes of old compound, and removing corrosion and salt residue from whatever leakage had occurred through the years. Once clean I made a large cone on each bolt with butyl tape and pressed it into the hole. Then with a helper holding a large screwdriver I tightened the nuts from below making sure the screw didn't turn to break the seal.

So now I have new control cables, a well lubricated steering system, a new fuel tank, new fuel pump and new Racor 500 MA large capacity fuel filter. In my spare time I took out my old Racor 120 and bought a small Facet cube pump at an auto store and made a polishing system for use in pumping out my tank annually, polishing the fuel if it needs it, and to polish any new fuel before it goes in the tank. The small pump is only about 25 gallons an hour but that will handle my whole tank in an hour.

Time to fire up the iron sail and head out to sea for trials then head north for fun and excitement.

For anyone with an old Edson I hope these lessons learned help. and since the compass comes out easily (three screws) it may be wise to remove annually and recoat those 4 long screws with never seize or equivalent. I also recommend getting a cover for the pedestal. Looking at prices for this stuff replacement is a fortune. Almost a grand for the base, over 500 for a wheel, almost 600 for the compass, almost 400 for the control housing, over three hundred for the pedestal guard, and a cheap vinyl compass cover is over 40 bucks now. Add in the idlers below deck and the system is over three thousand dollars, a few yards of sunbrella are worth the investment in making a pedestal cover to protect it. So now I have another project :>)
 
Jun 21, 2007
2,118
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
Jibes:

Thanks for such a detailed description of your project. Mine is a Merriman pedestal. Edson and Merriman were quite similar for the period of our boats' construction. Guess I was lucky six years back when I also had to take everything "pedestal" apart. As with you, one screw gave up it's grip fairly readily. The others came out with a longer shaft screw driver onto which a vice grip clamped around the handle and my full weight pressing down gave me enough leverage and grip to break the corrosion hold and remove...

... But I haven't been so lucky with the screws that thread into the sub-frp embedded aluminum plates underneath my cabin top traveler. A few screws will come out, neither but PB Blaster, heating with a propane torch, or a hand-held hammer type impact wrench either haven't budged the others or I can get a only 1/2 turn before they lock up. Fortunately, removing the traveler hasn't been an absolute necessity yet, so I continue to defer. But eventually I will have to do because to extricate and re-caulk the clamshell piece over my companionway, I will need to remove the traveler. From your experience, I think also that I will have to drill off the heads of my traveler screws. Then remove the traveler, lock vice grips (or pipe wrench) around the protruding screw shafts, and hope that with the right touch and feel ... and the added torque ... I will enable removal without the shafts snapping off inside.

p.s. I really shoud remove the compass soon, remove the sub-screws and re-coat with lanocote.
 
Dec 30, 2009
680
jeanneau 38 gin fizz sloop Summer- Keyport Yacht Club, Raritan Bay, NJ, Winter Viking Marina Verplanck, NY
I had same exp last week, compass came rite off no problem, the next 6 screws into the pedastal were in from 1977. They would not even budge, from exp I learned there is only one way to get them out, maybe....This week I bought PB blaster and they were set into the holes 3/8" so I sprayed the PB in and let em sit for an hour.I still think it was the small impact driver that actually got them out. Used correctly with a little counterclockwise twist, 2 sharp blows they came loose. I learned the hard way, stop with the screw drivers and visegripps, you will only make it worse. If your boats like most, there are plenty of other things to fix till next week...took me about 30 years but patience usually works... Red
 

NYSail

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Jan 6, 2006
3,181
Beneteau 423 Mt. Sinai, NY
Did the same job prior to splash but also did a complete rehab of the steering system.... New brake pads, new bearings, control cables and chain / wire. Got all bolts out but one. had to cut the head and then take vise grips to remove. Additionally I had my compass refurbished. Cost was about $250 and the thing looks brand new. Oh and remember....... When changing the chain / wire, it crosses in the pedestal.......... Lesson learned.
 

capta

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Jun 4, 2009
5,075
Pearson 530 Admiralty Bay, Bequia SVG
Aluminum will expand much faster than stainless or steel, for that matter. PB Blaster is indeed fabulous stuff, but if that fails a bit of heat can do wonders. Doesn't need to be a blow torch.
There is an anti-seize compound specifically made for aluminum and stainless that is gold in color instead of grey. When I purchase a new outboard I'll pull many of the bolts and coat them and years down the road they come out without trouble. Any screws or bolts in my mast are coated as well. Stuff works so well I've considered using it for inflatable boat bottom paint!
 
Jan 27, 2008
3,092
ODay 35 Beaufort, NC
Aluminum rate of expansion is around 12 millionths per degree per inch. Regular steel is around 6 millionths. This is very useful in shrink fitting parts together. But stainless steels are more like 9 millionths so the differential is not as great. Also the temper in the aluminum can be effected by temperatures in excess of about 375 degrees. So using a blowtorch is not recommended. Maybe a hair dryer or a heat gun on the low setting. Certainly worth a try. The problem with this installation is applying heat to the head of the screw it is 3 inches away from the thread engagement. It has a plastic washer under the head and the compass mount is some kind of reinforced plastic. The screw then runs through the control housing that is cast aluminum and the plate that holds the pedestal guard before getting to the threaded base. It would be best to cut the heads off, remove all the stuff and then apply heat near the threaded joint for best effect. You want to apply the heat to the pedestal base to get it to expand while keeping the screw cold. maybe put a damp cloth around the screw to take heat away while holding a hair dryer on the threaded base to expand the aluminum..
 
May 26, 2004
168
- - Oriental, NC
Jibes

Glad you got them out. Sounds like you now have a nice setup on fuel.
Goodwinds
DaveM
 
May 13, 2013
29
Tayana 48DS Phoenix, AZ
Glad you got 'em out without surgery! SS screws/bolts into aluminum can be nasty. I had a similar situation about 5 years ago on my Whitlock pedestal - took major force to get 'em out, and they were only about 7 years old at the time. When I replaced them (with Phillips head screws) I coated them with Lanocoat (clean off the excess or you WILL hear about it). I just took them out again a couple weeks ago, and they just came right out without any hassles (yes, I coated them again when re-assembling). I've also tapped holes into aluminum masts and booms, and used Lanocoat along with the nylon washers to install SS hardware - they always came apart again when needed, no visible corrosion.

Hartley
S/V Atsa
 
Jan 27, 2008
3,092
ODay 35 Beaufort, NC
Using my new polishing system I pumped 15 gallons of fuel into the new tank yesterday. Turning on the pump I let it run for quite a while to prime the system, fill up the Racor, and get the air out of the lines. I checked all of my joints for leaks and they were all leak tight. I then fired up the M25 and it started right up. That was a great feeling! I ran it for some time to get it up to temp and make sure it would keep running. Ran very well. New control cables are very smooth. A dive to clean the hull and prop and I should be ready for some cruising.
 
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