1973 Evinrude 18hp

[baron22]

I have a 1973 18hp Evinrude I recently acquired, I used it only a couple times last summer and it appears to have 2 issues. First there is water getting into lower unit, can this be fixed with a rebuild kit? Second the little bugger drinks gas like there is no tomorrow, runs very rich. I played with the lean/rich mixture adjustment but no change was noticed. Ran fine just very rich. Where should I start ffor the fuel issue? Model 18304A.

baron22

 

[HighTrim]

Re: 1973 Evinrude 18hp

Welcome to iboats.

You're going to be drinking about 2 gallons an hour at WOT, how much fuel are we talking about here?

Regarding the water in the lu, Im not quite sure what the problem is?? If you are referring to water leaking from between the lu and the midsection, that is normal. That is just spent cooling water. If it really bothers you, seal it up with Scotchgrip 847.

 

[tx1961whaler]

Re: 1973 Evinrude 18hp

What is the gallons/hour at wide open throttle (WOT) burn rate that you're seeing?

the lower unit can be resealed. A pressure test will show you where the water is getting in, so you don't have to guess at it...

 

[F_R]

Re: 1973 Evinrude 18hp

That motor has a fixed jet carburetor. The lean/rich knob only affects the idle mixture. The little gasket in the center of the float bowl may be missing or shot, which would make it run rich. Or it could be flooding. Or the fuel pump diaphragm may be perforated. Or, Or,

 

[baron22]

Re: 1973 Evinrude 18hp

The lower unit concern is water in the lower unit oil. I was looking at seal kit 18-2684 to resolve that. Sounds like pressure testing first might be in order. As far as the fuel deal I am looking at rebuild kit SIE-18-7042 its cheap and surely can't hurt. Yes I would say 2 gal/hr would be in the neighborhood but all the black crud coming out the exhaust turns a garbage can full of water black in a matter of minutes.

baron22

 

[HighTrim]

Re: 1973 Evinrude 18hp

Ah ic, I misread your post, and that is a problem.

You can pressure test it to determine the faulty seal, but personally I would just reseal the whole lu if it were mine. Be sure to change the drain and vent seals as well every time you change your gear oil, they are a one time use, and are a usual spot for water intrusion. May want to start there. If that solves your problem it was a cheap and easy fix.

May also want to decarb. Check the FAQ's.

 

[F_R]

Re: 1973 Evinrude 18hp

Turning a garbage can black with crud is absolutely normal, and cannot be stopped. It was made to run on a boat in the water, not a garbage can.