Exhaust seal

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atoyot
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Re: Exhaust seal

Post by atoyot »

Mutineer wrote:You have a 40 plus with a clutch?
Howdy.

With the clutch mechanism acting upon the prop shaft, the leakage you're speaking of would be there regardless of the engine being clutched or not.

I once put some high temp RTV inside the exhaust tube (of a 40+ l/s) while the gearbox was off, kind of built-up right at the (cleaned, degreased) inside edge. The sealant became dispersed between the gearbox and tube upon reassembly. The seal has lasted a good while and with only a minor leak over the last year or so since doing that. I suppose that was done because I had nothing better to do at the time [though the wife wouild disagree]; the dripping goo from that seal is now the dripping goo from the exhaust port itself. So the engine still needs a diaper after each use regardless of how the mess comes out of the exhaust tube.

-ted
There is nothing so useless as doing efficiently that which should not be done at all.
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Paul C.
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Re: Exhaust seal

Post by Paul C. »

I have a Forty Plus long shaft (FLP1548G9 July1969) which we use to power our sailboat out to the races on Sundays. It runs great, is light weight but after it has run for 30 minutes, it leaks oil so badly at the the bottom of the exhaust I have to take it off the boat and bring it ashore as a "slick' would spread throughout the marina if it was left to sit and drip.

Is there anything that could be done like replacing seals, bushings, etc? Or, do you just have to live with it?

Another thought, I run with a 10:1 oil mix. Would it help to change the needle so I could use a 25:1 mix?

I just love this engine but hate to deal with the mess. Thanks for any thoughts.

Paul
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outboard
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Re: Exhaust seal

Post by outboard »

As you will read in many parts of this forum, if it doesn't leak oil it's not a seagull.
It's part and parcel of owning a seagull. The oil will always find a way out especially down at the bottom of the exhaust. No gaskets or seals can stop this.
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atoyot
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Re: Exhaust seal

Post by atoyot »

Hi Paul

If you want "clean" and "responsible" (in the eyes of some detractors, that is) then you want a Honda 4-stroke, 2hp with a 3-bladed prop (standard).

http://marine.honda.com/Products/ModelDetail/BF2

I've had one and they're fine for getting in & out of a marina or an inlet, to the place where one can sail. They're a bit noisy, but then if you're putting up with a 40+ then this can't be an objection. They only weigh 28 pounds or 62 kilos, very friendly on the back when installing or removing.

As far as oil goes, in which part the world do you live? Here in the states, a chain of boating stores has begun marketing a purely vegetable-based oil for marine use:

http://www.suite101.com/content/biodegr ... ed-a210473

I find better starting down at around 16 or 20 to 1 mix, rather than at 25:1. Do a search here on the BBS, on using Coleman camp stove fuel (I don't want to hijack this thread when it's been written about already). That fuel evaporates completely, so imagine veggy oil and Coleman's. A cleaner salad of fuel, all else roughly being equal.
There is nothing so useless as doing efficiently that which should not be done at all.
- Prof. Peter Drucker
Paul C.
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Location: Pennsylvania, U.S.A.

Re: Exhaust seal

Post by Paul C. »

Thanks for the feedback on the 40+ exhaust oil issue. Yeah, I kinda figured I would have to live with this but was hoping I could minimize the problem with the oil slick and this motor really lays one down.

Would it help to change the carburetor needle to permit a higher gas/oil mix (25:1)? That is one thought I was toying with. I live in northeastern Pennslvania in the U.S. and the Marine Police and Fish and Game officials seem to frown on leaving a big oil slick. I've been taking the motor it off the boat everytime I return to the dock so the slick doesn't spread. But, I do like the motor.

Also, I looked at the link to the 2 cycle vegetable oil. Do you think it would change anything? A slick is a slick is a slick, no? Don't know if it would do much good to explain the vegetable oil tothe Marine Police if it looked the same. Thanks for all the feedback.

Paul
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RAY SWANN
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Re: Exhaust seal

Post by RAY SWANN »

I was wondering if any members have tried machining the brass bush/casting,
and fitting a standard oil seal?
You would still get some oil leaking from the drive shaft bush,but It should cut down
on the oil loss.
As far as I can remember late model seagulls had standard oil seals fitted.(not sure about bearings)
A simple jig could be made up to fit in the lathe chuck,but is there enough material in
the casting to allow for the counter bore locating the oil seal to be cut without
weakening the casting.
This together with a low oil fuel mix the motor should be some help(if it can be done)
Just wondering....... :|
SOME DO, SOME DONT,THOSE WHO DONT, DO A BIT
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