OPTI 150 - Should it do that ?

[philip]

I have a new to me Mariner OPTI 150 (2000) - At tick over when first started my son noticed water coming out from under the bottom cowling .Is this normal or should I be worried?

From looking at the workshop manual I think its OK and coming from two exhaust ports under the bottom cowling but I am a bit new boat paranoid.

(Will try to attach diagram from workshop manual when I can work out how to do it)

[Robert1]

It might be the tell-tail. This is the used cooling water leaving the engine. If so, this is definetely normal...in fact, you should have been worried if you didn't have a tell-tail. If it isn't the tell-tail, then I'm not sure what it could be. On an Opti 150, the tell tail would be a pretty powerful stream, not a little dribble.

Hope this helps,
Robert

[philip]

Robert,

Thanks for the response - The tell tail is as it should be and the smart guages indicate water temp and pressure are OK.

I suppose what I really need to know is - are there exaust outlets under the bottom cowling ? This would explain what I am seeing. I would have thougth someone out there would have taken the cowling off and this would save me having to do it if I don't have a problem.

Cheers

Phil

[Richard B]

Originally posted by philip
are there exaust outlets under the bottom cowling ?

What do you mean, Philip... do you mean:
a) Lower than the base of the main engine cowling
b) Covered by the "bottom cowling"
c) something else?
A picture or diagram may assist!

[philip]

Richard,

b) Covered by the "bottom cowling"

Trying to attach diag.

[Richard B]

If you're having problems with attaching a picture, does this: http://www.rib.net/forum/showthread.php?threadid=256 help?

[philip]

Richard,

Thanks for the link - fingers crossed diag should be here:

Have also e-mailed you a picture .

Cheers

Phil

[philip]

And now I've got the hang of posting pictures here's a shot of what the OPTI is connected to - Our new baby.

[tue]

The two slots at the bottom are the exhaust openings above the water. They are connected to the grp cowling via a rubber bellow. They allow exhaust to be vented from above the waterline aswell as through the prop. This is mainly done to cut down on the back pressure the water causes and allows the engines to run better.

[philip]

Tue

Thanks for your reply - your going to regret selling me that workshop manual – a little knowledge being a dangerous thing and all that .

It would appear from my manual that the rubber bellow connects to the round hole in the previous diagram – see below. And that the two slots vent freely underneath (covered by) the bottom cowling.

If this is the case would I expect to see cooling water running down the drive shaft housing from a gap between the bottom cover and the drive shaft housing? Should I be concerned?

[tue]

Well I think we have solved the mystery today. If you are in doubt next time you flush the engine remove the lower cowling first and see if it does come from the slots or just the hose. Any other questions don't hesitate to contact me again.

cheers for now

[philip]

Tue

Thanks very much for your help on this - I’ll keep my eye on it next time I’m flushing.

What an excellent forum this is it even cures people of paranoia. – for free.

Now lets see what else I can find to worry about …..