Bilge Blower Installation

[LadyAnya]

I am in the process of installing 2 bilge blowers in my 88' Sunrunner Weekender and I would like some advice on the proper way of doing it. I am confused about a few things such as, exhaust vents and intake. What is the proper routing of the hose,etc?

I decided on 2 blowers for more protection since I have a small child that will be boating with us.

Thanks

 

[Greg Mrozinski]

Re: Bilge Blower Installation

Lady A,

You need to make sure that your hoses are run such that there is a cross flow/exchanging of air inside the bilge area. Some smaller boats use one blower (intake and hose to direct fresh air into the bilge area and the blower w/hose to expell it out) and some boats use two blowers (a double configuration of a single blower). Can you post some pics of the current system so we see where you are starting from? One thing to consider is if your boat has only one blower now then you need to make sure that there is enough power and the electrical wire is of sufficent size to run a second blower.

 

[LadyAnya]

Re: Bilge Blower Installation

I'll try to post a picture later of what I have.

 

[LadyAnya]

Re: Bilge Blower Installation

I have not been able to take pictures yet. At the moment, I have one 4" blower mounted on each side of the transom. I am going to replace the vents I have with new ones and with 4" collector box. How do I route the hose? How many do I need?

 

[Greg Mrozinski]

Re: Bilge Blower Installation

Well both blowers will be expelling air out (sucking air out of the bilge area). So you need two 4" hoses, one on each blower, running from the output side of the blower to their respective exhaust vents. Separately you will need two 4" air intake hoses running from their respective intake vents down into the bilge area in front of the engine area.

One question I have is why are you adding an additional blower? I know what you posted as a reason up front but most boats like yours only have one and if it is properly installed and operational it will provide more than enough ventilation for the size of your engine compartment. Adding a second really won't increase the safety. Plus if it is set-up for one blower then you will most likely have to add additional vents which are a pain. I don?t like to see anyone cut into their hulls unnecessarily. One of the common problems with bilge vent systems are their hoses get crushed or they collapse from the suction of the blower. Most manufactures use a hose that is similar to a vinyl dryer vent hose. If you replace the vent hoses make sure you use a stout form of hose that won't collapse on its self when the blower is switched on.

 

[LadyAnya]

Re: Bilge Blower Installation

Thats a good explanation. The main reason I want two blowers is added safety. Its a 24ft boat and I think I can get by with one, I just want to be extra safe.

 

[Greg Mrozinski]

Re: Bilge Blower Installation

Anya,

I understand what you thinking and why but I fear you are building a false sense of security. The number of bilge blowers has nothing to do with it. You will still have to run the blower(s) the recommended length of time to ensure equal amount of "safety". IMHO could be a lot of work for nothing. Your call no problem.

 

[PiratePast40]

Re: Bilge Blower Installation

If you want to modify what was part of the OEM system, it's probably a good idea to understand the regulations and requirements. Here's a linkto the BoatBuilders Handbook and the section on ventilation: http://www.uscgboating.org/regulations/boatbuilder_s_handbook/ventilation_landing.aspx
The figures you need to determine total flow are at the end of the section.

It's not rocket science but you really should know what the system is supposed to do before you go making modifications.

 

[LadyAnya]

Re: Bilge Blower Installation

Thank you Greg. I appreciate your concern. I will look more into what you are saying.