easily removed and lightweight engine cover

[galeus]

I posted this question in February and am nearing doing something about it. Can I pick your brains a bit further. Ideally I would like this engine surround/ cover to be 'easily' removable' hopefully by just myself. Any body thought up some innovative hinge to their engine cover or similar, that makes the whole lot easily removable; maybe something like a fixed horizontal tube bar at the back of the engine that some forks, a bit like tuning forks could slip over attached to the removable bit, hard to explain, but any good ideas out there?


I need to lighten my very heavy engine surround, a job I used to do with my wife but now not possible. It is a substantial rectangular box with the bottom missing made of plywood, plasterboard, loft insulation and zinc mesh holding it all in. The cover slopes at the end where the exhaust is and I'm hoping to hinge/pivot it from there backwards for maintenance. So the plan is to get back to the plywood and use some lightweight but effective sound insulation. Space is reasonably good as my current engine is more compact than previous 1.5 BMC. I'm sure many have you have done something similar and recommendations and advice are very welcome. I've looked at ASAP as a starting point, but loads of others on the internet, with claims for their decibel reduction. I would imagine getting it all to stay in place might be another consideration

 

[Tranona]

A photo would help to stimulate practical ideas. "light" and good insulation do not tend to go together! Sealing all possible paths for sound to escape is important but difficult to achieve as the engine needs air to run.

 

[justanothersailboat]

"made of plywood, plasterboard, loft insulation and zinc mesh holding it all in" - that sounds like a heavy combination of materials. Presumably the plasterboard is serving as a sound-insulating layer with loft insulation between it and the outer structural ply?

It sounds like there are multiple possible directions here. "Lighten my heavy engine surround" sounds like either (a) strip the plasterboard part of the sound insulation and live with the possibly worse noise, (b) replace the plasterboard and loft insulation - you can buy sound-insulating sheets that are like two layers of foam with a heavy sheet something in the middle, which are expensive, but would probably save a bit of weight... or (c) actually make a new box that's lighter in fundamental construction, which could get high-effort and fairly expensive, but is the only way to really make a huge difference.

"hinge/pivot it" - is rather independent of weight changes... doesn't necessarily lead to removal... but you could use a gas strut to hold it up if this is mostly about regular checks/servicing rather than total access.

or I think I see what you mean with the description of a tube and forks, and suspect you might be able to find an easier approach with what are called detachable hinges or lift off hinges. If used sideways you would need something like a carefully sized/positioned wooden block to prevent the cover sliding sideways off the hinges until lifted over it.

 

[PCUK]

12mm ply box coated with resin and tissue inside and out, with 50mm insulation and hinged with gas struts to aid lifting.

 

[galeus]

A photo would help to stimulate practical ideas. "light" and good insulation do not tend to go together! Sealing all possible paths for sound to escape is important but difficult to achieve as the engine needs air to run.

Fair comment, unfortunately not there for a couple of weeks

 

[galeus]

"made of plywood, plasterboard, loft insulation and zinc mesh holding it all in" - that sounds like a heavy combination of materials. Presumably the plasterboard is serving as a sound-insulating layer with loft insulation between it and the outer structural ply?

It sounds like there are multiple possible directions here. "Lighten my heavy engine surround" sounds like either (a) strip the plasterboard part of the sound insulation and live with the possibly worse noise, (b) replace the plasterboard and loft insulation - you can buy sound-insulating sheets that are like two layers of foam with a heavy sheet something in the middle, which are expensive, but would probably save a bit of weight... or (c) actually make a new box that's lighter in fundamental construction, which could get high-effort and fairly expensive, but is the only way to really make a huge difference.

"hinge/pivot it" - is rather independent of weight changes... doesn't necessarily lead to removal... but you could use a gas strut to hold it up if this is mostly about regular checks/servicing rather than total access.

or I think I see what you mean with the description of a tube and forks, and suspect you might be able to find an easier approach with what are called detachable hinges or lift off hinges. If used sideways you would need something like a carefully sized/positioned wooden block to prevent the cover sliding sideways off the hinges until lifted over it.

I think I've got a good idea about lightening the existing 'box' and trying to keep it rigid + new soundproofing. I've sort of moved my thoughts now as to how to make the hinges disengage when I need total access without me having to get down pulling hinge pins out, thats how I've come up with this thought which is probably not doable that I described above. I'm not at the boat for a couple of weeks so cant get any further yet. Thanks for your thoughts

 

[galeus]

12mm ply box coated with rein and tissue inside and out, with 50mm insulation and hinged with gas struts to aid lifting.

Yes sounds good, but at this point I would like to keep the existing surround as the wood colour and figure goes with what's there

 

[William_H]

If you really want light weight then build a new box with carbon fibre and polyester resin. Rounded corners and suitably placed sections of foam to stiffen the panels. Yes needs a bit of good design but much lighter than ply. Make a wood and plaster male or female mold. Add light weight sound deadening as needed. ol'will

 

[PCUK]

If you decide to go down the disengaging hinges route and can't find any I could make you a pair depending on the layout of the box and how it's sitting.

 

[Caraway]

Yes sounds good, but at this point I would like to keep the existing surround as the wood colour and figure goes with what's there

Do your research. Google works. Car Insulation, Van Insulation, Sound Deadening
If you want a lighter box then GRP is a step towards that. If you continue with the wood you will always think it is still too heavy.

 

[Pye_End]

Do your research. Google works. Car Insulation, Van Insulation, Sound Deadening
If you want a lighter box then GRP is a step towards that. If you continue with the wood you will always think it is still too heavy.

Are they suitable for engine compartment?

 

[Boathook]

Are they suitable for engine compartment?

On this one they say marine and it is Flame retardant to FMVSS302 what ever that spec is.
SOShield 20mm All in One Insulation and Sound Deadening Mat