Thank you for the responses, all helpful. I discussed the missing and stripped set screws on the brass adapter bushing with a friend that knows Duffy's, he strongly suggested replacing it. I decided to go ahead and get a new main bearing as well, as long as I'm taking things apart, just for peace of mind. Folks at Duffy were helpful, and even sent me a PDF of the original owners manual for my year/boat. Still wish I could find a schematic though, I do better with pictures LOL . Next stop, packing gland! Thanks again.
I keep driving by this place. Is this shop still supportive? In Stuart FL at the S W corner of Ocean Blvd and UseLess 1.
Hello from Colorado, where I can't find anyone to work on an electric boat. We have an ElectraCraft LSR 18 that was running very noisy. This thread has been awesome, thanks everyone. The motor was most of the noise but I also noticed the forward bearing doesn't look great. Please see the attached picture. Would you recommend this be replaced?
Ouch… The short answer is yes: You are looking at good old rust stains most likely from low grade steel. Yes, remove the bearings, lock-washers, whatever the bad metals are, then replace with better quality steel. This is very low tech, a shaft, a bearing, a seal etc, easy to fix, but it may be involved if you need to haul at a yard, hire mechanics with pullers and other specialized tools. Do it yourself, easy peasy if you have the experience and the tools. (Guessing you don’t since you found this page and asked the questions. Sorry.)
As I mentioned, the motor is very noisy when turned by hand. We haven't found anyone local to work on it yet, the first several shops we tried don't work on DC motors. Any suggestions in Colorado or for mail-in service would be appreciated. My wife found one shop that wanted $250 to evaluate it, is that about right? Here is a very short video, does this noise suggest anything? Here is the motor sticker:
Wow.. That was noisy, sure sounds like bad bearings, or something. To pay someone $250 for “evaluating” the motor is crazy, for that money you should get a an overhaul. (Well, not quite, but brushes and bearings are not made of gold) A small electric motor is pretty low tech. Your nearest fork lift, of golf cart repair shop will be the best bet, refurbish the motor for $500 or whatever, half for labor, half for parts. (On my electric boat, an 18’ Duffy Balboa, the motor was the least of the problems, the controller, the charger, the throttle was the, expensive deals, then the batteries..)
I opened the motor and found the bad bearing. Unfortunately, it doesn't have a part number on it. My budget caliper is showing .98" ID, 2.04" OD, .59" wide. There are tiny notches in the outer ring, if those are separating the balls then there are 15 balls. This is a GE motor from about 20 years ago. Any suggestions for choosing a replacement bearing? I appreciate the help so far, I'm having fun and making progress.
I measured in millimeters and it seems like I have a 6205ZZ. I ordered this one on Amazon, any feedback appreciated: https://www.amazon.com/NTN-Bearing-6205ZZ-Clearance-Shielded/dp/B003MULZ54 Sorry about not doing more research before posting. The odd measurements in inches threw me off. Looks like the $8 caliper is working fine.
Generic bearings are probably ok. Unless Chinese knock-offs using bad metals and cheap everything else. Always heard good things about SKF: https://www.skf.com/group/support/splash
If your Amazon bearing doesn't work just take your old one into any decent bearing shop and they should be able to measure it and find you one. I have always been partial to Timken or SKF bearings myself.
What ever bearing you use that does work, you have to ensure the belt tension is not over tight when reassembled. This is what probably killed the motor bearing. How are you doing on the shaft bearing? BTW, Your caliper looks just like my Sears/CrapMans tool. Works like a champ.
Works great: When I went to machinist school 1973/1974 I would have given my left nut for a digital caliper like that. Really.
Probably why my eyes are so messed up, trying to make out the lil lines between 0.001" increments. Yes, that new lil display works and pretty darn on the spec. It is not temperature compensated, I have to keep hitting the Zero tab as I move around. Now, I think this would have helped us.
I went to machinist school 1973/1974 Dude, stop quoting dates. We know your old. Don't let the rest of the kids know it. Most were born before then.
Hello, Duffy Experts: I've got an unusual 2010 Duffy M160 (sort of a catamaran hull) that I've owned for a couple of years. I've been maintaining it myself, even though we have a dealer here in coastal South Carolina. I've recently discovered that I have a "flat spot" in the throttle control, meaning that as I accelerate or decelerate the throttle handle, it will hit a spot on the potentiometer (aka rheostat) where the motor drops out momentarily. As soon as I'm past that spot, the motor resumes. If you move the handle quickly, you almost don't notice this flat spot. Using an ohmeter, I've confirmed that the potentiometer itself has this flat spot, and I've obtained a replacement potentiometer. However, upon removing the throttle assembly, I found that a kind of black aluminum cam is attached directly to the potentiometer shaft, as shown in the picture. A setscrew through the cam to the potentiometer shaft can be removed, but I haven't been able to budge the cam off of the shaft. I've been careful not to be carried away, since I don't want to destroy the aluminum cam. I've checked with Duffy, and they only sell the entire throttle assembly, not any of the parts, such as the cam. So, I'm looking for suggestions on how to get this cam off of the potentiometer without ruining the cam. Any suggestions? Thanks, in advance! https://ibb.co/Fx0brdn
If it works the way it is, I wouldn't mess with it if it simply has a flat spot in one small area of throttle.
Yes, Capt J, it's more of an irritant than a real problem, but it really does irritate me, so I want to fix it. The throttle is simple with only 3 electronic parts, so it should be straightforward, except for that damned cam. Suggestions are very much appreciated!