Loud Engine Blower on Jeanneau SO 43 DS

[Prairie Chicken]

Our engine blower is loud and runs continuously in the heat of a Med summer. Apart from noise suppression, does any one else have any bright ideas? The blower is almost louder than the engine.

[colemj]

Why would the blower be running when the engine is not? Some blowers are quieter than others. Also, the mounting configuration matters (how much head pressure, what it is mounted on, etc). If it is old, the bearings may be going or there may be chips or crud on the blades. Have you listened to a newer blower of the same type?

Mark

[a64pilot]

Makes it sound like it has a temp switch that switches it on, as opposed to it being wired straight from the ign.?

[Prairie Chicken]

A64, you're right. Our initial thought was that it should have come on with ignition & as it didn't we suspected a faulty ignition switch. The blower didn't come on when you switch on the ignition but came on about 15 minutes after engine start & remained on until we shut down a couple of hours later. Then after a couple of hours lunch break the blower came on when switching on the ignition. It turns out the system is working correctly as there is a temp sensor in the engine compartment at the blower air intake duct. The problem is how loud the blower is, and I think colemj is on the right track. No, we haven't heard another blower but that may be in our future if soundproofing doesn't do the trick. The engine has <100 hours on it so doubt if it is the blades.

[dbostrom]

A little late to the party here but if you change to a squirrelcage blower you'll get more efficient and quieter performance.

See this:

http://www.xylemflowcontrol.com/file...43000-0405.pdf

A bit bulkier but will fit and is vastly better than the cost-reduced part supplied with the boat. Note the datasheet points on life expectancy; there's an identical blower available with better lifespan but higher cost, if you prefer.

[ranger58sb]

It might be the blower is mounted directly to a hard surface, and it's the vibration you're hearing. Try remounting, using something like 2" sanitation hose as a stand-off.

-Chris

[HappyMdRSailor]

Originally Posted by dbostrom

A little late to the party here but if you change to a squirrelcage blower you'll get more efficient and quieter performance.

See this:

http://www.xylemflowcontrol.com/file...43000-0405.pdf

A bit bulkier but will fit and is vastly better than the cost-reduced part supplied with the boat. Note the datasheet points on life expectancy; there's an identical blower available with better lifespan but higher cost, if you prefer.

I'm not 100%, but fairly certain this is the blower I have... It's noticeable to sure when it's going, but not unpleasant...

Originally Posted by ranger42c

It might be the blower is mounted directly to a hard surface, and it's the vibration you're hearing. Try remounting, using something like 2" sanitation hose as a stand-off.

-Chris

As suggested above, this might be a solution... Tell us how the noise is offensive... Did it always sound kind of loud, or increase in volume lately?

[Randyonr3]

If the blower is comming on based on a heat issue, get rid of the heat and the blower wont come on..
How to get rid of it is up to you to design..

When I installed a new refer unit, it was air cooled, and the compartment would get pretty warm, I plumbed a 3 inch duck up from the bilge into the compartment for cooler air and ran a 2 inch tube throu the cabinits forward to the forward head with a small muffen fan pulling the air out.. the muffen fan was conected throu a reley so when the unit went on, the cooling process would flow.. the compartment stays pretty cool now..
You'd be surprised at how much air a small 2 inch muffen fan will push..

[Prairie Chicken]

HappyMDsailor, the boat is quite new to us so I can't comment on how it sounded previously. The initial post was on our first day taking the boat out. Since then we've become more familiar with the blower & it's habits.

Randy, the heat is primarily ambient air. Then it takes very little engine heat for the thermostat to reach it's setting & turn on the blower.

The blower is located below the aft bunk. There are two large air vents, about 4" each, in the passage between the cockpit and the scoop. One is the intake into the area of the blower; one for the exhausted hot air. The exhaust is right beside the helm.

Since the initial post we have sound-proofed the blower. That did help, but the blower is still noisy enough to annoy the captain. I think, however, it is what it is. Replacing the blower is an option and we'll have a look at that link for the squirrel cage blower.

[chuckr]

have you postedthe issue on the jeanneau owners web site? a lot of knowledgeable jeanneau owners you may have or had similar problems.

[Prairie Chicken]

Thanks chuckr, I did, but I haven't checked back there for a while to see if there has been anything added. I did get a better understanding of the system from them though.

[Cheechako]

Get rid of the thermostat and put in a switch. Turn it on when you start the engine. If it's too loud when the engine is running replace the blower, it's defective.

[a64pilot]

A squirrel cage blower you will not hear with the engine running, even at idle.
If it annoys him it's not worth putting up with, fix it.
Wire it so it comes on when the switch is on, before engine start, that way you hear it run every time before you start the engine and know it's still working. You can't over cool the engine compt.

[Phoenician]

Originally Posted by Cheechako

Get rid of the thermostat and put in a switch. Turn it on when you start the engine. If it's too loud when the engine is running replace the blower, it's defective.

This is exactly how I have it on my Jeanneau. In addition, I was able to reduce fan noise further by tightening the fan mount (it was somewhat loose), thereby significantly reducing the vibrations.

I can't comment on how useful or effective the fan really is, but I do wonder... The exhaust fan is inside a duct that starts in the middle of nowhere in the engine room, and blows out air that is at worst lukewarm outside... Is that the configuration in your DS?

[Prairie Chicken]

No Phoenician, not the same. The blower is located under the aft bunks & large ducting leads to the vents in the cockpit. There is significant hot air being blown out of the exhaust vent. Putting a switch on the fan as A64pilot suggests makes good sense but does nothing to eliminate the sound. We do believe the fan is necessary so don't want to eliminate it or put the fan on a reostat (another suggestion we got). The squirrel cage fan sounds like the best alternative though if we need to go that way.