CD 25 engine exhaust sollution?

[Isaac]

Like many CD 25 owners, I have had difficulty keeping the engine well closed while motoring, especially when the wind is from behind me. While i have vents that can be adjusted to the direction of the wind, sometimes it's not enough.

One possible sollution: install a nicro mini solar vent to the top of the engine well. adjust the propeller so that it pulls air (exhaust) out. The vent works with the sun and also with batteries.

two possible problems.
1. The suction power is not so great, and may not be enough for the engine well.
2. The propeler is made of plastic and may melt due to the engine heat.

But then again, maybe these concerns are not valid. Anyway, does this sound like a possible sollution? or just a crazy idea?

Any comments would be greatly appreciated.



capedorynyc@aol.com

[Mark Yashinsky]

If the search function works, look back in the archives (last year) about dealing w/ the exhaust and fresh air in the outboard wells. Sounded like a number of skippers came up w/ various solutions, that worked for them (and were able to keep the hatch closed w/ the engine running).

[Tom B.]

I don't think the solar vent will pull enough air to make much of a difference. I have wondered if the small plastic in-line bilge blower fan with some duct work would do the trick. I not sure how loud the small electric blowers are but I do think they will move enough air to work.



tomb5050@aol.com

[David Brownlee]

Nine years ago there was an after-market adapter available for OMC engines (referenced in the OMC literature). It consisted of a steel cap with a hose nipple that fitted over the exhuast outlet on the aft side of the outboard's shaft. One had to drill and tap two holes on the shaft to attach it, then hook up a hose that led the exhaust gases down, under water, and out of the well. The lid could then be kept closed.

David Brownlee
CD 31 #1 "Windrush"
(our first CD was a 1976 25 footer)



dbrownle@sas.upenn.edu

[Jon]

Isaac,

We can either focus on getting the used air out, or on getting new air in to the motor. Has anyone run a "clean air" line into the motor from a clean air source, such as the dead space below the fuel shelves? Perhaps this could be plumbed directly into the motor cover via flexible hose. In this case it wouldn't matter how little O2 was floating around beneath the hatch. Also, the need for any sort of blower/fan would be eliminated, as the motor would just suck in its own fresh air.

Jon
s/v Sovereign

[Al Levesque]

Isaac,

We can either focus on getting the used air out, or on getting new air in to the motor. Has anyone run a "clean air" line into the motor from a clean air source, such as the dead space below the fuel shelves? Perhaps this could be plumbed directly into the motor cover via flexible hose. In this case it wouldn't matter how little O2 was floating around beneath the hatch. Also, the need for any sort of blower/fan would be eliminated, as the motor would just suck in its own fresh air.

Sounds like a lot of work. We stuffed the tail of a rope into the upper exhaust and ran for full days with the compartment closed and without any concern about venting. (We had removed the engine handle and also kept the front of the compartment closed.) Used it that way for many years with never a problem. Some predict that the extra vent is needed to facilitate starting. We never found that to be a problem.

There was much discussion about venting previously. Might find it interesting in the archives.

Al

Jon
s/v Sovereign

albertlevesque@cove.com