Happy with the Pod !!!!!

[Original Riptetide]

So it’s been a while since I have been in my dads boat. Dad passed away and Now I have his boat. He got a pod installed on it since the last time I was in it. Now I notice the boat has a lot harder time getting on plane, when I come off plane it almost fully submerged the motor with water. I do not ever remember this problem when the motor was mounted on the transom. Even with a 200 hp it would be a hard time getting on plane with 4. I am thinking maybe I should get a different pitched prop or may some hydro foil.

 

[fishin solo]

Common misconception is people think going from cruising speed to zero in 3 seconds is normal...... Anything will get swamped that way.

 

[YachtMech]

So it’s been a while since I have been in my dads boat. Dad passed away and Now I have his boat. He got a pod installed on it since the last time I was in it. Now I notice the boat has a lot harder time getting on plane, when I come off plane it almost fully submerged the motor with water. I do not ever remember this problem when the motor was mounted on the transom. Even with a 200 hp it would be a hard time getting on plane with 4. I am thinking maybe I should get a different pitched prop or may some hydro foil.

There area few things to remember when boats get pods, first is you are creating a huge shift in the center of gravity in respect to the center of buoyancy, this amplifies the effect of swamping the motor when slowing down, @fishin solo is correct as most people just cut the throttle rather than slowing down progressively before they learn proper boat handling.

Also in general you don’t pod boats under a certain size, if you talk to Armstrong brackets they actually don’t recommend podding under 24’, Unless the boat is particularly heavy as it shifts the center of gravity farther than practical. Also in cases of smaller boats its considered best practice to glass in the old engine cutout into a flat transom as the possibility of swamping the stern is greater due to the CG shift.

In your case that 500lb engine (plus 100lb bracket) has shifted the CG about 2 feet back, and on a 21’ boat that equates to 10% CG shift without adding a sufficient amount of buoyancy. the bracket will probably provide about 300lbs of positive buoyancy when mostly submerged which helps to partially compensate for the shift in the CG. However by comparison, the hull profile of the same area would provide about 800-1000lbs of buoyancy. That hull is probably sitting at 2500-3000lbs, so moving 1/6th of the mass 10% rearward will have a drastic effect on how the boat comes on and off plane.

So what this equates to is an excessive amount of squat when accelerating and decelerating, when decelerating your engine is literally trying to pivot under the boat around a point that defined by a relationship between the CG and CB, and when accelerating the engine is trying to push itself under your boat. This can sometimes be mitigated to some degree with trim tabs or a foil, however a foil will reduce the fuel savings from the podding and reduce your top speed. Its also likely you will have to actively adjust trim at different speeds to avoid porposing. In the end this boat probably should not have been podded, he was probably sold on the idea of fuel savings and higher speeds, however its all basically a compromised engineering project. Do pods work, yes, but not on all boats, as to be properly effective there need to be actual planning, calculation and engineering work, just buying a pod and bolting it on will not provide the best solution unless someone has done the work to design it for your boat. This would not be the first time that a boat has been podded when it really probably shouldn't have been.

 

[Original Riptetide]

Wow that’s most certainly puts this into perspective. And gives me a lot to process. I do agree that dad should not have let himself get talked into putting this pod on the boat. I am lead to believe that he was not very happy with it since it was put on. Thank you for your input and time explaining the issue.

 

[Rain City]

There area few things to remember when boats get pods, first is you are creating a huge shift in the center of gravity in respect to the center of buoyancy, this amplifies the effect of swamping the motor when slowing down, @fishin solo is correct as most people just cut the throttle rather than slowing down progressively before they learn proper boat handling.

Also in general you don’t pod boats under a certain size, if you talk to Armstrong brackets they actually don’t recommend podding under 24’, Unless the boat is particularly heavy as it shifts the center of gravity farther than practical. Also in cases of smaller boats its considered best practice to glass in the old engine cutout into a flat transom as the possibility of swamping the stern is greater due to the CG shift.

In your case that 500lb engine (plus 100lb bracket) has shifted the CG about 2 feet back, and on a 21’ boat that equates to 10% CG shift without adding a sufficient amount of buoyancy. the bracket will probably provide about 300lbs of positive buoyancy when mostly submerged which helps to partially compensate for the shift in the CG. However by comparison, the hull profile of the same area would provide about 800-1000lbs of buoyancy. That hull is probably sitting at 2500-3000lbs, so moving 1/6th of the mass 10% rearward will have a drastic effect on how the boat comes on and off plane.

So what this equates to is an excessive amount of squat when accelerating and decelerating, when decelerating your engine is literally trying to pivot under the boat around a point that defined by a relationship between the CG and CB, and when accelerating the engine is trying to push itself under your boat. This can sometimes be mitigated to some degree with trim tabs or a foil, however a foil will reduce the fuel savings from the podding and reduce your top speed. Its also likely you will have to actively adjust trim at different speeds to avoid porposing. In the end this boat probably should not have been podded, he was probably sold on the idea of fuel savings and higher speeds, however its all basically a compromised engineering project. Do pods work, yes, but not on all boats, as to be properly effective there need to be actual planning, calculation and engineering work, just buying a pod and bolting it on will not provide the best solution unless someone has done the work to design it for your boat. This would not be the first time that a boat has been podded when it really probably shouldn't have been.

Yeah but what would you know?

 

[YachtMech]

Yeah but what would you know?

not much

 

[CIVANO]

So it’s been a while since I have been in my dads boat. Dad passed away and Now I have his boat. He got a pod installed on it since the last time I was in it. Now I notice the boat has a lot harder time getting on plane, when I come off plane it almost fully submerged the motor with water. I do not ever remember this problem when the motor was mounted on the transom. Even with a 200 hp it would be a hard time getting on plane with 4. I am thinking maybe I should get a different pitched prop or may some hydro foil.

Get a 4 blade prop to try.

 

[scott craven]

Depending on how the pod is built and installed, it may take on water.
I'm sure you have checked, but if there's an access plate, you may want to take a look.

 

[Original Riptetide]

Depending on how the pod is built and installed, it may take on water.
I'm sure you have checked, but if there's an access plate, you may want to take a look

It does have an access plate. I have verified it does not leak or take water inside. Adding un wanted weight. Thanks again for the suggestions

 

[ReelSlim]

It also looks to me that this isn’t a hull extension pod more of a pod/bracket. Like has been talked about there is a lot to it but if I was putting one on a boat after having one that is done correctly I would only do a hull extension pod. Hopefully you can get it sorted out and enjoy your dads boat. I’m sure he would like that...

 

[Pineapple Express]

Check the engine height. On these extension brackets the engine has to come up a bit from the "normal" reference line. It's hard to tell in that pic but I'm guessing that motor is too low.

 

[Original Riptetide]

Check the engine height. On these extension brackets the engine has to come up a bit from the "normal" reference line. It's hard to tell in that pic but I'm guessing that motor is too low

Thank you I felt that way as well. When I look at how much higher the motor was when it was on the transom looks like there is almost 8 to 10 inches lower which I always assumed it needed to be that because of the extra 2 feet added by the pod. which I guess leads right into the suggestion from YachtMech.

​

 

[Fisherman Rob]

I wonder if someone who knows what they are doing could modify the bracket to turn it into more of a hull extension, adding buoyancy? Also what about the pod are you happy with? Sounds like you are not happy with the pod

 

[AlK]

If it were my decision, I would take it off. Why spend more money, when you have no guarantee that it will rectify the situation.

 

[Original Riptetide]

I wonder if someone who knows what they are doing could modify the bracket to turn it into more of a hull extension, adding buoyancy? Also what about the pod are you happy with? Sounds like you are not happy with the pod

I like the idea of the pod, I am just not having the best of luck with This one. It is like trying to get on step towing a barn. To the point where it’s hard to get on step with 3 guys in the boat everyone has to move forward to help get rhe balance back. Which would line up with some of the suggestions on here. I know my dad paid a lot to get this done and he was very unhappy with it after but the guy who did basically told him to pound sand. Dad is now gone so it’s my issue now. With the weather getting nicer I figured I should get on this.

 

[salmonkiller01]

You have the same pod/bracket that I have on my hourston. Made by fibre pro in Campbell river. They have been making brackets since the 80’s. Your issue is not the bracket
Put a straight edge in your keel , lower engine. Cavitation plate should be 4-5” above keel line.

 

[Doubleheader]

I like the idea of the pod, I am just not having the best of luck with This one. It is like trying to get on step towing a barn. To the point where it’s hard to get on step with 3 guys in the boat everyone has to move forward to help get rhe balance back. Which would line up with some of the suggestions on here. I know my dad paid a lot to get this done and he was very unhappy with it after but the guy who did basically told him to pound sand. Dad is now gone so it’s my issue now. With the weather getting nicer I figured I should get on this.

I had the same boat but with modified transom mount. I would suggest moving the tank 3’ forward where that goofy fishwell is. Even when I had a 225 4stroke on the back she sat much better in the water. I just took measurements and ordered a 45gal plastic one from west marine that fit right in, routed filler out to port gunwale and added new vent. Turned the old aluminum tank that was leaking into a fishwell with drain pump.

 

[Doubleheader]

And yes for every 1’ back your engine is mounted you likely have to come up an 1”, so around 3” higher than when it was transom mount. Anti-vent plate should be around 3” above keel I’d imagine.

 

[YachtMech]

Thank you I felt that way as well. When I look at how much higher the motor was when it was on the transom looks like there is almost 8 to 10 inches lower which I always assumed it needed to be that because of the extra 2 feet added by the pod. which I guess leads right into the suggestion from YachtMech.

​

I’m pretty certain your transom is partially glassed in already, so make sure your are measuring that correctly, it looks to be at the correct height in comparison to what it would have been in stock form. regardless of who made the pod and how its been made and the flotation provided, this boat should probably not have been podded, there would have been nothing wrong with how it was stock. Pods in this application were developed initially to provide a easy solution to convert an inboard boat to outboard. Whomever recommended it did not likely have a strong background in naval architecture or nautical sciences and was likely promoting what has really become a fad (its embarrassing for the industry, so many people that are making recommendations to customers have no formal training or certification) Yes it has its benefits if done right on the correct vessel. The whole theory that is applied to this is that providing greater hull plane area without increasing the width of the boat will increase its stability in regard to reducing the pitching moments. Other ways to conceive what is happening is to look at sailboats or skis, the longer and narrower the hull or surface area the higher the maximum speed of that design will be.

The idea of these bolt on brackets is flawed, proper hull extension pods are really the only thing that will provide an appreciable difference without having to suffer any undesirable side effects.

Unfortunately, in your case if you contact the manufacturer or the shop that installed/recommended it, they will unlikely (nearly impossible) be able to provide support in a constructive way that will result in the boat going back to handling the way it used to. There is no way they can change the position of the motor, pitch or blade count of the prop, or provide any simple change that will rectify the problems you are experiencing. You can’t get around the mathematics of the problem without great expense.


Your realistic options are as follows;

-Add trim tabs which will slightly mitigate the problem, you have the power to use the tabs to force the aft end up (or bow down as some people conceive it)

-add a proper hull extension pod (modify the current pod, this will likely be VERY costly)

-Remove the pod, and the transom modifications and plug all the holes and gel coat

-Contract someone to remove the pod and build a proper hull extension (incredibly expensive and will take time), this requires cutting out the lower half of the transom and is by far the most “correct” way to obtain the benefits that people are looking for.

 

[Doubleheader]

These boats came from the factory with a bracket option. My buddy had one with a df225 on the back worked fine, did sit stern heavy compared to the old two smoker 225 though. The biggest issue is the weight in the back, the fuel tank in the rear is the flaw.