500/520 DB official thread

I’m probably looking at 2 weeks lay-up time. New shaft is only about 3 days to fabricate but the old one still isn’t pulled.
 
Wish I had something to share... sorry that happened although it’s good you made it home with everything in tact.

If you dont mind what does a new shaft cost?
 
So I want to share my shaft failure on our return from the Bahamas. I’ll give you a little run down of the trip first.

We arrived in the Bahamas on July 1 and for the first two and a half weeks the weather was perfect. We worked our way from the Berries down thru Nassau and the the Exumas. We went as far as Staniel Cay Yacht Club. Weather pattern changed at the time we were at Staniel Cay and we started to get several days of steady wind. Our plan was to head to Harbor Island but we would have been fighting the seas heading east and decided to change our itinerary and just work our way back home. At the time we were in Highbourne and winds were now steady and no end in sight. So we ran to Palm Cay Marina on Nassau which wasn’t a bad cruise with a following sea. We ended staying there for 5 days waiting for condition to improve. Not a bad place to be stuck so no complaints here. Our next run would be over deep water so I knew conditions could be bad so we waited it out for an “acceptable” day.
This is where the failure happened. Our next run would be from Nassau to Bimini. We ran for 2 hours over deep water in a following sea with swells combined with 3-4’s. Boat was handeling it well and it really wasn’t bad. I was running at 1900 rpm. Once we got to the Bahama Bank off the north end of Andros conditions improved. I decided to bring engine up around 1970-2000 rpm to make a little time since we still had another 3 hours. I would say not more than 5 minutes later I start to feel a small vibration. I figured I must have picked up a line or something so I slowed down and backed down to see if that would maybe help. It didn’t so I kept her at 1900 rpm. Heading to North Bimini, there is an “S” turn between Gun Cay and North Cat Cay. After I went thru the S turn, the vibration seemed to had gotten worse.
Once we got to Bimini, I waited until the next morning to dive under the boat expecting to see something wrapped around my Starboard prop. Nothing....... Spun the prop and everything seem normal. I assumed whatever it was fell off backing into the slip.
Well when we went to leave Bimini the vibration was still there and certainly now prominent enough that we had to slow cruise across the Gulf Stream at 8 -9 kts. Not fun.....I actually ran up the port engine which seemed to reduce the vibration and taking load off the starboard.

When we arrived at Key Biscayne, I dove under the boat again and now grabbed the prop and check for any play. Sure enough the prop felt like it was rocking as if the prop was loose. As I watched it closely, I could see the end of the shaft moving with the prop. I knew that wasn’t good and can only mean one thing. Sure enough when the prop was pulled the next day, the shaft was cracked under the prop. I’m super lucky I didn’t loose the prop or have a situation of it flapping around like a wagging tail before it broke off. It appears the cracked started spiraling down the shaft which was probably a good thing.

It has me wondering how this could happen. I never hit anything and I’ve owned the boat for 10 years. I did have the cutless bearing replaced and swapped out my props back in April but I’ve put about 30 hours or more on the boat since then so I wouldn’t think that has anything to do with it but who knows. Metal fatigue?

Would love to hear any thoughts on this......


View attachment 89464
An opinion -
First, note on the port propeller that it is assembled incorrectly consequently the shaft threads may have higher stresses at the propeller depending upon how the nuts were tightened.
If the propeller was not fit first without a key and the location on the shaft marked but rather first installed with the key the propeller may have not fully seated on the taper. Shaft keys can slide up the shaft or have a burr and prevent the propeller from fully seating; one would not know this unless the prop was first installed without the key and location marked on the shaft.
I think this is the most probable cause; there was a lateral stress caused by the key which could fatigue the shaft at the location seen and considering the situation of the reversed nuts I suspect an installer error. The crack probably started at the keyway and the rotational loads caused the unusual spiral propagation.
The port prop really needs to be removed and the shaft dye penetrant tested all along the keyway up to the cutlass.
As an edit - most likely the bore in the propeller is no longer round or the taper is probably deformed so that needs to be looked at. In fact if this situation happened on my boat everything is suspect and I would pull both sides and have all the shafts and propellers inspected and lapped. Hopefully, you are not faced with a new propeller also....
And, looking at the picture a second time it is quite evident the key did slide up too far (into the keyway transition) and prevented proper seating of the propeller on the shaft taper - definitely an installer error.
Now - in many of the SR installations the shaft keys had a dowel pin and the shaft keyway was drilled so that pin could lock the key in position. Many times yards will utilize a drift and hammer the key out of the shaft keyway and shear that pin off - if you look closely that may have been the case at some point in time. Regardless, even with the location pin the propeller needs to be fit and located without the key first.....
 
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Thanks for your insight and recommendations ttmott...... It’s unfortunate that someone who’s business is reconditioning props and suppose to be an expert in the field most likely installed the prop(s) incorrectly after changing the cuttless bearing.

Rlynch03- The cost of the shaft replacement..... labor and fabrication is $6,600.
 
Sliding Glass Door:
Does anyone have the manufacturers name and info for these doors? Mine needs some adjustment e.g., door won't roll without holding the hand down. It catches each screw. Doesn't seem like a big deal but it use to slide without holding the handle down. The family can't seem to get use to this new process.

Thanks
Rich
 
Sliding Glass Door:
Does anyone have the manufacturers name and info for these doors? Mine needs some adjustment e.g., door won't roll without holding the hand down. It catches each screw. Doesn't seem like a big deal but it use to slide without holding the handle down. The family can't seem to get use to this new process.

Thanks
Rich
There were some posts on sliding door repair and replacement a couple of months ago... Maybe it was @carterchapman that had to have his fixed..
I believe if you look at the bottom of the door edges there is a hole to access the guide truck adjustment screw. But more times than not the truck needs to be replaced. To remove the door (three man project) adjust the truck rollers in the full up position and lift the door up then rotate the bottom outward. I believe ours are made by Taylor Made Products.
https://www.taylormadeproducts.com/hardware/rollers-and-cars/
And watch this -
 
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Has anyone replaced the swim ladder on their 52DB? Mine is starting to malfunction so I think it's time.
Are they made by GGSchmidt? Part Nunber?

Thanks
Tom
 
Has anyone replaced the swim ladder on their 52DB? Mine is starting to malfunction so I think it's time.
Are they made by GGSchmidt? Part Nunber?

Thanks
Tom

Mine is made by GGSchmidt and their website still shows what looks to be the originals From our boats. Mine is slightly different than yours though. I also reconditioned mine to surprising results.
 
I’ve been getting water dripping out of my cockpit speaker above the sliding door when I run my bridge a/c. I looked at the unit under the helm and the pan is full as normal with no water around the pan and the water is draining as planned through he hoses out of the pan. Problem becomes that somewhere it is leaking before it gets to the sump box. I can’t seem to find where the hose is supposed to route to?
 
Mine is made by GGSchmidt and their website still shows what looks to be the originals From our boats. Mine is slightly different than yours though. I also reconditioned mine to surprising results.
When I bought the boat the ladder was tweaked and had a cracked weld. I had it repaired but its never operated smoothly and the other day the lower step popped out. It's time to replace.
 
When I bought the boat the ladder was tweaked and had a cracked weld. I had it repaired but its never operated smoothly and the other day the lower step popped out. It's time to replace.

Gotcha - I am pretty sure you will find your exact replacement on the TTSchmitt website.
 
I’ve been getting water dripping out of my cockpit speaker above the sliding door when I run my bridge a/c. I looked at the unit under the helm and the pan is full as normal with no water around the pan and the water is draining as planned through he hoses out of the pan. Problem becomes that somewhere it is leaking before it gets to the sump box. I can’t seem to find where the hose is supposed to route to?
Both the raw water discharge and pan drain hoses route through the side of the helm where the AC unit is into that "gunnel" area on the starboard side of the bridge, then aft about two feet then down through the penetration and down next to the entertainment center cabinet then from behind the entertainment center through the back wall and then they both tie into the starboard common drain behind the ice maker in the cockpit. Neither of these drain hoses make it aft far enough to drip where you are indicating. If the hoses were cracked and leaking you would most likely see water on the solon carpet around the entertainment center.
 
Both the raw water discharge and pan drain hoses route through the side of the helm where the AC unit is into that "gunnel" area on the starboard side of the bridge, then aft about two feet then down through the penetration and down next to the entertainment center cabinet then from behind the entertainment center through the back wall and then they both tie into the starboard common drain behind the ice maker in the cockpit. Neither of these drain hoses make it aft far enough to drip where you are indicating. If the hoses were cracked and leaking you would most likely see water on the solon carpet around the entertainment center.

Mine is routed in the same manner.
 
Has anyone changed the blowers to Jasbsco squirrel cage blowers? I wanted to do this to quiet them down but I have 14awg wiring going to the blowers and a 7.5amp breaker to run them. Others have said change out the breaker but 14awg is not large enough to run 12amps that the blowers require.
Also there is a blower control box that looks like it is tied to the fire control system and wires into and out of that

With all of the Blower talk lately mine have started Acting weird. It is like they aren’t receiving enough voltage... they are both running Real slow or not at all. If I tap on the blowers they will pick up speed for a minute.

Anyone know where this blower control box is mounted? I wonder if my issue lies with it.

I don’t mind replacing the blowers but I doubt they both are bad at the same time.

Both of my momentary switches light up as if they are engaged.

I need to check the voltage at the blowers next.

Any other thoughts?
 
With all of the Blower talk lately mine have started Acting weird. It is like they aren’t receiving enough voltage... they are both running Real slow or not at all. If I tap on the blowers they will pick up speed for a minute.

Anyone know where this blower control box is mounted? I wonder if my issue lies with it.

I don’t mind replacing the blowers but I doubt they both are bad at the same time.

Both of my momentary switches light up as if they are engaged.

I need to check the voltage at the blowers next.

Any other thoughts?

Checking the voltage will give you a definite answer. Like you said seems like a coincidence that they both die at the same time. The control box for the blowers is in the DC breaker panel in the lazzarette to the right of the entrance to the engine room. I changed mine out to the squirrel cage blowers and they are so much quieter it is much better when they are in. They are so quite I forget to turn them off after a few hours after everything is shut down. I leave them running for a few hours after a cruise to help get some of the heat out of the engine room.
 
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Checking the voltage will give you a definite answer. Like you said seems like a coincidence that they both die at the same time. The control box for the blowers is in the DC breaker panel in the salon to the right of the entrance to the engine room. I changed mine out to the squirrel cage blowers and they are so much quieter it is much better when they are in. They are so quite I forget to turn them off after a few hours when everything is shut down. I leave them running for a few hows after a cruise to help get some of the heat out of the engine room.
Engine Blower Module Small.JPG
 
I’ve been getting water dripping out of my cockpit speaker above the sliding door when I run my bridge a/c. I looked at the unit under the helm and the pan is full as normal with no water around the pan and the water is draining as planned through he hoses out of the pan. Problem becomes that somewhere it is leaking before it gets to the sump box. I can’t seem to find where the hose is supposed to route to?

Open up the access panels on the bridge on the starboard side and check for a leak visually or feeling around with your hand while unit is running. If there is a leak in any of the hoses inside that area, I believe water could make its way between the bridge floor and the cockpit ceiling where the speaker and lights are located. I know I’ve had water drip out of one of the cockpit lights after I stripped the bridge canvas and cushions and wrapped the console in preparation for a tropical storm. I assume some rain water made its way in the opening in the seat in front of the console and made its way around to the starboard gunnel (wire chase way).
 
Open up the access panels on the bridge on the starboard side and check for a leak visually or feeling around with your hand while unit is running. If there is a leak in any of the hoses inside that area, I believe water could make its way between the bridge floor and the cockpit ceiling where the speaker and lights are located. I know I’ve had water drip out of one of the cockpit lights after I stripped the bridge canvas and cushions and wrapped the console in preparation for a tropical storm. I assume some rain water made its way in the opening in the seat in front of the console and made its way around to the starboard gunnel (wire chase way).
For some reason my brain never went to the fresh water hose on the a/c. This only happens when the unit is running to this point I’m thinking a/c verses rain water. I have been in those access panels and haven’t noticed water. I have ordered a boroscope to see better underneath there and will be checking more thoroughly this week.
 

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