Hi Folks
I own a 2012 Cruiser 32, purchased in 2020. Her swim platform gas springs were worn, making raising and lowering the swim platform very difficult. As with other models from this era, she has a gas-spring-assisted swim platform. From what I've seen, the Cruiser range (32, 33, 34, 37 built between 2010-present all use the gas-spring-assisted method to make lowering and lifting the swim platform effortless.
As it was time to replace the gas springs and this procedure is not detailed in the owners manual, I requested instructions from Bavaria who promptly replied with very brief and rather elementary instructions. These might have sufficed for an experienced mechanical artisan, but unfortunately I wasn't able to make sense of this, and pursued the internet for further clarification. To my surprise, I was unable to find instructions on how to achieve this, and so as with many boating projects, I had to figure it out for myself.
(https://media1.svb-media.de/en/images/508174/bavaria-gas-pressure-spring-for-cruiser-32-37-swimming-platform.jpg)
1900kN Gas Spring for Bavaria Cruiser 32 swim platform (and likely larger models too seeing as this is specifically listed for Cruiser 37 also).
I ordered the replacement gas springs from SVB (https://www.svb24.com/en/bavaria-gas-pressure-spring-for-cruiser-32-37-swimming-platform.html) and once they arrived, spent some time understanding how the gas springs would fit into the swim platform hinge. It soon became apparent that the entire hinge would have to be removed to fit the replacement springs, and this in turn would require the swim platform to be removed in its entirety (owing to the length of the hinge mechanism). Given the 'dead' weight of the swim platform, I was concerned about attempting this project in the water (read, "bye bye swim platform") and held back until we had to haul out for antifouling.
Important: These gas springs are loaded to 1900kN. That's a substantial force, especially in an articulated mechanism such as a hinge. It can cause severe bodily harm if handled improperly. My gas springs were completely exhausted, which meant that removal was simple as the hinge could operate freely, but if they had any charge left, this could cause them to snap open or shut. Take care! So where I had the swim platform fully open (horizontal) during the removal process due to the exhausted gas springs, it had to be angled at roughly 60-degrees to the closed position to reinstall it again with the new, charged gas springs in place. In the same way, if the old gas springs have any charge left at the time of removal, it will be necessary to open the swim platform until the locator holes are aligned, then insert a pin through the locator holes (see photos and description below), before removing the screws from the transom.
So the process went something as follows:
- The boat yard had a forklift which meant that with the boat on the hard stand, the forklift could support the swim platform (in the horizontal position) while I undid the screws securing the hinge to the transom. As is to be expected, these screws appear to be sealed with 5200 or similar permanent marine sealant. As detailed above, since my gas springs were worn, they offered no resistance on the hinges and the platform could be fully opened for removal.
- Label the hinges (port/stb) before removal as they fit either way into the swim platform, but only one way onto the transom. You'll hate to discover that you swopped them around once you've secured the screws with adhesive sealant! :o
- With the four transom-side screws on each hinge removed (which was accompanied by colourful language, a heat gun and a hand-operated impact driver*), the swim platform was free and could be lowered to the ground. This made working on the rest of the hinge assembly substantially easier (as opposed to doing so suspended in the air.
- I repeated the process to remove the four screws securing each hinge to the swim platform. Given that the screws on the transom side were hard to crack loose, I wanted to loosen those on the swim platform too before removing the platform from the transom, but couldn't get the impact driver into the gap. Similarly the problem with a screwdriver, which is why the entire hinge had to come off either which way.
- With the two hinges now free, I could pull these out of the swim platform. They were much longer than expected, given the comparatively short length of the gas springs. Then came the head-scratching to understand how to remove the gas springs from the hinge mechanism.
- I was able to unscrew the piston rod from its mounting by hand with relative ease which meant that I could now lift the piston out of the hinge mechanism (as the mountings can pivot). The cylinder end was harder to remove as the threaded male mounting on the cylinder can turn freely in the cylinder, whereas the female thread on the hinge mounting was well and truly seized. Presumably, I could have heated the hinge mounting (female thread) to expand and 'release' the cylinder male thread mount, but I wasn't keen to bring a heat gun anywhere near a compressed gas cylinder (albeit a worn one), and instead drilled a small hole in the male threaded mount on the cylinder (not the cylinder itself) so that I could hammer it with a punch to unthread it. The latter did the trick and soon the cylinders were free from the hinge mechanism.
- With the old gas springs removed, I used the opportunity to give the hinge assembly a good wash, shined the stainless a little, and greased the moving parts. Likewise, I removed and clean the old adhesive on the transom, platform and inside the 16x bolt holes on both.
- I fitted the new gas springs into the hinge assembly, first threading the cylinder end of the gas spring into the hinge, and then threading the previously removed mounting on the piston rod end.
- Then came the difficult part. I aligned the locator holes and inserted a pin through the holes such that the hinge was in the correct position for installation. Then I aligned the mounting at the top of the piston rod end between the hinge sides and clamped the entire assembly into a bench vice. As I tightened the vice, the piston rod end eased into position, and I could secure it using 4x new hex screws. In hindsight, I should have made a video to illustrate this as it's not easy to explain, but at the time I had my hands full and didn't think to do so.
- With the hinges now assembled, I inserted them back into the swim platform about 70% of the way. After masking off the area around the hinges, I applied a liberal amount of 5200 inside the screw holes, on the area where the hinge would be applied, and on the screws themselves, before sliding the hinge all the way in and securing the 8x hinge screws on the swim platform.
- With the help of the forklift, we raised the swim platform until the hinges aligned to the transom. I masked off the hinge area on the transom, and applied a liberal amount of 5200 in both the screw holes are well as the hinge plate area (and the screws on insertion). As the hinges were now at an angle with the securing pins in place, it wasn't possible to simply screw the hinges back on as the platform had to be partially raised. To do this I attached lines from the cockpit winches to the top (cable) attachments on the swim platform, and pulled the platform in towards the cockpit using the winches until the hinges were in place. The lines to the winches helped to keep the platform in place while I secured the screws. The transom was open about 60-degrees with the locking pins in the hinge. With the last 8x screws on the transom secured, I was able to push the platform open slightly and remove the locking pins from the hinge (in my case an allen key).
- The platform was now operational, presumably as it was the day it came from the factory. With the worn gas springs, it took my wife and I with effort to lift the platform. With the gas springs in place, my 9yo can push it open and pull it close with minimal effort.
Personally, I don't think this project can be attempted with the boat in the water. If I could do it again, I would have constructed a platform, eg. scaffolding, behind the transom, so that I could do the work on my own time, and not be at the mercy of the boat yard forklift and their forklift operator (although they were very helpful and assisted to lower and raise it for no extra charge while I did my thing).
The attached photos serve as the process followed. I've numbered and annotated them for ease of future reference.
* Hand-operated Impact Driver: This was the first time I was introduced to this tool, and it helped me immensely with a number of screws that were tough to remove. If you're not familiar with this tool, it applies the hammer impact on a body which twists a screwdriver point while forcing it down into the screw head, thereby reducing the instance of stripped screws while helping to undo seized or tight screw threads. Here's an example of what it is and how it works: https://www.youtube.com/watch?v=yq_-zlBgVUE (no affiliation of any kind, just sharing for interest).
Brilliant post! Thank you, especially for the excellent photos. It can be done with the boat in the water - I've seen the swim platform of a Cruiser 37 removed whilst the boat was in the water, but several strong guys were involved!
Good to know. I had dome this alone, so guess with several hands it's possible. I assume being stern-to the dock would also make it slightly easier. The hardest part (alone) was in fact aligning the hinges to the transom once fully assembled in the swim platform without damaging the transom in any way. Once aligned and in place, it was relatively easy thereafter.
An excellent post. Thank you
Brilliant contribution :) :) :)
My boat will go through these steps... still today figuring out the dimensions and strength of the gas spring for my 2014 bavaria 41 Cruiser (swim platform is identical with Bavaria 40 cruiser). Gas prings for Swim Platform Cruiser 32-37 are 1900N, dimensions unknown. Gas springs for 46-51 are 2500N, dimensions unknown.
I would order gas springs directly at gas springs distributors (more or less 280€ each in 316 stainless steel), should I know the strength and dimensions.
I suppose the locking pin is here to prevent the platform to "fold" too much towards the transom, so it is possible to mount the transom screws. Did I get it right ?
I'm sorry I can't help with details of the struts for the other models. If the 41 platform is a similar size and weight as the 37, wouldn't the 37 strut work all the same?
As I see it the 'locking pins' (I'm not sure this is the right name, but went with this for the purpose of the explanation) are there to prevent the hinge from snapping shut when removing or reinstalling the bathing platform onto the stern. And yes, as you correctly put it, to be able to insert the screws through the hinge bracket into the stern.
Thank You. I suppose the 40/41 platform is larger than the 37, since the 40/41 is almost 4m wide and the platform extends through most of transom. I´ll post when I know more. The Bavaria P/N for the 40/41 cruiser gas springs is 344513 ... 5 weeks delivery time... looking for alternatives.
Hi David. A great article. Did you by any chance take the dimensions of the struts? I have a UK supplier that is 1/5th of the price but the need to know the dims.
Thanks Ant. PS here is the PDF for the OEM in Germany
No, sadly I don't! And I had the platform and hinges out in January while the boat was on the hardstand to do some gelcoat repairs, so could have measured them then. Sorry!
Hello,
Thank you for the perfect instructions to do this job.
I'm wondering how much could be the weight of the swimming platform of the cruiser 32?
Regards,
Attila