'64 Evinrude Fastwin 18hp - Lower Unit Leak

P

pckeen

Commander
Joined
Jun 20, 2012
Messages
2,067
Hello Everyone,

I just bought a pair of '64 18 HP Evrinrude Fastwins, plus a spare parts motor. The lower unit in one of them is leaking. I'll check the oil in both to confirm which one (I believe I know which), but I want to know how to diagnose and hopefully fix this problem. I'm have little knowledge about engines - can someone help me out?

Here is an image of the two engines.

 
G

geoffwga1

Petty Officer 1st Class
Joined
Aug 8, 2010
Messages
394
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

tbfosback said:
Pressure test the lower unit. I have used one of these to get pressure into the lower unit while spraying the seams with a soap water mix out of a spray bottle..
Gear Lube Oil Drill Pump, 3 1/2 GPM - Seachoice 19191 - iboats
Follow that up with a seal kit
Lower Unit Gear Housing Seal Kit for Johnson/Evinrude, GLM 87606 - Sierra - iboats
I hope this helps...
Click to expand...

What a great buy.Two of the best from Evinrude and in apparently mint condition.Would it be cheeky to ask how much you paid for them?
Regarding the leak,are you certain it is a leak and not just unburned oil finding it's way out of one of the drain holes(good scenario).Or is it coming from round the prop area ,or through one of the screw holes.(less good scenario).If it's round the prop it is probably the seal that is gone,not a huge job but one that entails removal of the skeg at least and the seal replacing,while doing that it would be worthwhile to replace all the other seals while you have the LU off and replace the pump impeller.If it's just coming out from one of the screw holes you will likely just have to remove and clean the screw,dip it in OMC perfect seal and replace it.There are many posts on here on how to do all this,it's not hard.
Check the top secret files above.Congrats again on your buy,I am green.
geoff69a1
 
kfa4303

kfa4303

Banned
Joined
Sep 17, 2010
Messages
6,094
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

Hi pc. Nice pair of motors. Milky-white gear oil is the tell tale sign of water intrusion into the lower unit. Here are some great links that can walk you through the entire job of replacing the oil seals. You can get a LU reseal kit right here at iboats for about $25. The only special tool you need is a standard, automotive oil seal puller which are about $7. You'll also want to get a tube of 3M 847 gasket sealant, or similar product. Here are some link that walk you through the whole job.

http://forums.iboats.com/johnson-ev...l-kit-1968-evinrude-fastwin-18-hp-601481.html
http://forums.iboats.com/johnson-evinrude-outboards/fastwin-lower-unit-seal-faq-277190.html
Evinrude / johnson 18-20 hp LOWER UNIT disassembly - YouTube
HOW TO PULL SEALS FROM LOWER UNITS - YouTube
Maintaining Johnson E & FD Serie
 
P

pckeen

Commander
Joined
Jun 20, 2012
Messages
2,067
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

Hi - paid $375 for the set of motors. I plan on keeping the best one, and selling the rest, but would prefer to sell a repaired motor. Thanks for the links - seems simple enough.
 
G

geoffwga1

Petty Officer 1st Class
Joined
Aug 8, 2010
Messages
394
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

pckeen said:
Hi - paid $375 for the set of motors. I plan on keeping the best one, and selling the rest, but would prefer to sell a repaired motor. Thanks for the links - seems simple enough.
Click to expand...

That's not bad for two motors And a parts motor.There doesn't look to be much wrong with either of them so good luck to you.let us know how you get on with the leak.
 
P

pckeen

Commander
Joined
Jun 20, 2012
Messages
2,067
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

I am a complete newbie to engines.

Ok- so I checked both lower units today - I wanted to confirm which one leaks, and which one does not. The one with the suspected leak had new oil in it - so told me nothing. The one that was supposed to be good had used oil in it - it was black/brownish, with no sign of milkiness. I took a picture of it. My understanding is that this oil is exactly the way it is supposed to look - i.e. - no sign of problems. Am I correct?

The red line in the photo is a reflection from a red object nearby. The color here is a fair representation on what is in the engine.

 
kfa4303

kfa4303

Banned
Joined
Sep 17, 2010
Messages
6,094
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

HI pc. That oil looks fine. As you said, as long as it's not milky-white you're good to go. What ever motor that came out of should be fine. You can even bolt that lower unit onto the other power head if need be. So far so good.
 
kfa4303

kfa4303

Banned
Joined
Sep 17, 2010
Messages
6,094
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

You want to use 80-90w Hypoid outboard lower unit gear oil. It's specially desigined for water/marine use. You can get it for about $5 a quart at Wal-mart. There are lots of brands, but it doesn't matter much IMO. You'll also want a little hand pump so you can fill the gear case properly from the bottom up. They should sell it right next to the gear oil. Be sure to replace the small, white, nylon crush washers found beneath the DRAIN and VENT screws. Here are some pics and vids on how to do the job. Holler if you get stuck.

How to change the lower unit gear oil in the 4 hp Johnson Evinrude vintage outboard engine - YouTube
 
P

pckeen

Commander
Joined
Jun 20, 2012
Messages
2,067
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

OK - well replacing the lower unit oil in the good motor was easy. The only problem is someone at some point began to cross-thread the thread for the drain plug, so it took a bit to get it back in.

I have got the parts to replace all the seals in the lower unit on the 'bad' motor - we'll see how that goes.
 
kfa4303

kfa4303

Banned
Joined
Sep 17, 2010
Messages
6,094
Re: '64 Evinrude Fastwin 18hp - Lower Unit Leak

It's not too bad. Just be careful you don't damage the aluminum bearings the seals are found within.
 
You must log in or register to reply here.
Top