Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

[Sea18Horse]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Like a watch! Congrats!

Cheers...............Todd

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

That in itself does not indicate a lower unit leak. You are going to get that when you run a 24:1 gas / oil mix on one of these old kickers in a barrel.

You know, I think that lower unit was stored dry. That little bit of oil that cam out with the water was more like the surface of the water in the barrel than lower unit oil.

As you can see, I put the motor in the barrel one more time before the maiden voyage. I got the same slick, which looked nothing like the LU oil I added.

With that I also don't, any more, think that I have a lower unit leak. I'm no physicist, but here'e what I think happended:

A lower unit, full of air, goes into the water, with no seals on the drain/vent screws. Air is constantly trying to escape and suck in water. Ad some vibraton to boot, and you have a situation where water is drawn in, otherwise good seals not withstanding. That water, of course, included some of the same oil I was seeing on the surface of the water. Result: a smattering of water from the drain hole, with a coulpe of drops of blackish oil on top. Makes sense to me.

As to the maiden voyage: The motor ran good. It was a little weaker than I had hoped, but not bad. I discovered that I didn't tighten well enough that sleave compressing the high spead needle packing bushings. I found the sweet spot for the high spead needle. Then, as soon as I would let go of the knobb, it would slowly rotate from the vibration. I don't quite get the physics on that one, but the solution is simple enough.

Just to be safe, I'm going to drain and check the oil once I pick up more lower unit oil.

Thanks again for the help.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

NOPE, the lower unit still leaks.

I haven't drained the oil yet. But, I did notice the oil stain on the driveway where it was parked.

I pulled it back in the garage and put some cardboard under it. After a day of work, I had a pretty good stain on the carboard -- bigger than a softball.

I've looked it over as best I could, suspecting it was comming from the prop shaft, from which I removed a trolling length of fishing line, and have not yet replaced the seals. Still the seals looked good, and the shaft was not groved.

Best I can tell, the oil is leaking from the ding in the back of the housing. I'm pretty confident about this based on wiping the unit clean last night, and inspecting it tonight.

The dent if quite visible in the pic below, but you can see from the other pic, that it does not seem to affect the seal seat.

ANY SUGGESTIONS?

So far, my plan is open it up again and file down any warping I can find. Then, I read, there is a sealer I can use that some folks substitute for the spaghetti seal. Can anyone tell me what that is? Should I keep the spaghetti seal and add the sealer or ditch the seal all together?

 

[wbeaton]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

I have yet to see a 1950's OMC that didn't need a lower unit reseal. The spaghetti seal should have sealed any leak near that ding as long as you used the sealer with it. The sealer is 3M Scotchgrip 847. Sierra makes a lower unit seal kit for your motor. You might as well do it now. Otherwise, you will be posting back saysing it still leaks.

Also the compression numbers I gave in the link you posted are good. 75 psi is fine.

On second thought, I think the sealer may now be called 3M Scotchweld 847.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Wayne:

No, I didn't use the sealer with it. I will this time, and see if that works before taking a file to any deformaties. Thanks.

 

[Chinewalker]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Also, keep in mind that you WILL get a bit of oily drainage from the exhaust on those motors after running. If you run the motor and immediately store it upright, that drainage will show up as an oil spot under the motor. COMPLETELY normal.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

It was definately leaking. I changed the oil and got 2-3 good "glugs" of water before the oil that followed. That led to an immediate disection, inspection, and cleaning. The spaghetti seal must not have seated properly as it was mangled

I replaced the seal and also used gasket maker/sealer this time and it seems to have done the trick. No more LU oil running down the skeg and no more water in the oil after a couple hours on the lake.

Now its time to rebuild that first pressure tank....