Crankshaft condition

[fleetwin]

salnaes wrote:

This weekend I bought two Johnson 20hp 1967. Now I will take out the crankshaft from both and check their condition. If one of them looks fine, I will exchange my crankshaft, which is pitted and leaking fuel, with the best Johnson crankshaft. I appreciate all good help on this matter, and if none of the Johnsons have a proper crankshaft, then I will try all advices you’ve been willing to share with me. Thank you for all help.

Again, please don’t pull that powerhead apart until you have removed your upper seal to confirm that the crankshaft pitting is causing an issue.  Again, perhaps the seal is just bad, or perhaps misinstalled.   I just don’t want to see you rip that freshly rebuilt powerhead apart unless a problem in confirmed with crank condition…

[Crowsbeak]

Here is a photo from when I tore my 15032 18 Hp down. It looks like there might be a bit of room where you could adjust where the seal rides.  Perhaps a nylon spacer or washer could be added between the upper bearing and the seal?

1954 Evinrude 7.5 HP
1954 Evinrude 15 HP
1954 Gale 12 HP
1955 Johnson 10 HP
1956 Johnson 10 HP
1956 Gale 12 HP
1956 Evinrude 5.5 HP
1958 Johnson 7.5
1960 Evinrude 18 HP
1973 Johnson 6 HP

[salnaes]

Ok, I’ll give it a try. Thanks

[fleetwin]

Again, please don’t pull that powerhead apart until you have removed the seal and have a look…

[salnaes]

Hi again. The years went by, and I still haven’t done anything with the seal. I have pulled out the two crankshafts from the two Johnson 25 horse powers that I bought for 80$, and they don’t look brand new either. Now I’m selling my boat and Evinrude 18 outboard, and the buyer will have to deal with the problem. I will inform the buyer prior to a purchase of course. I have purchased a brand new seal, and the two crankshafts will be provided too. So then it’s up to the buyer to decide what to do.

I will provide the buyer the link to this thread at aomci.org, to let she or him read all advices you generously have provided my on this matter. I will also post images of the two crankshafts I have pulled out from the two Johnsons I bought, so anyone on this forum may give some thoughts on the crankshafts conditions if you still wanna do me that favor.

Again, I can’t express strong enough how happy I am for all the help I got at aomci.org. Without this forum, it would have been very difficult to learn how to as an amateur I could be able to totally overhaul an Evinrude 18Hp from 1960. But I managed, almost. Thanks’ to you folks.

If you wanna have a look at my boat and outboard, visit this URL: https://www.fuglognatur.no/helt-andre-ting/  Then you may click on the images that work as menu items to access https://www.fuglognatur.no/evinrude-fastwin/ or https://www.fuglognatur.no/with-200-restaureringsprosjekt/

Remember I’m Norwegian, so you might use some translation app like Google Translate or Chat GPT or whatever.

Images of crankshafts will be present soon.

[salnaes]

Here’s two images of the least worn crankshaft. The other crankshaft look to bad, so I thought it was no good idea to have an opinion of it.

But if anyone wants to give an assessment of the wear shown in the images of the crankshaft, I appreciate it.

[salnaes]

Update. I removed the flywheel now to have a proper inspection of oil and gas spill. It’s wet under the flywheel on the armature plate where magnetos are located. It’s also wet on the throttle cam underneath the armature plate and also on the bottom of the lower motor cover. So suddenly I got a little nervous if this gasoline and oil spill could be causing an engine fire due to sparks from the braker points.

I really don’t know if all this oil and petrol spill is caused by the upper seal issue, or if there are other leakages elsewhere. I’m a little worried since it seems to be to much spill. So this is quite depressing, since I’m about to sell both the boat and the Evinrude as a complete package in a huge boating event early in May.

My only  chance in such a short period of time is to remove the upper seal and put the new seal on the crankshaft a little higher than before. I also have to clean the armature plate and the lower motor cover from fuel.

To be able to place the seal properly and a little higher up on the shaft, I was wondering if a washer underneath the seal could do the trick? What do you think? After all the seal has to be installed using a spesial tool to tap the seal evenly down in the upper bearing on the crankshaft. I don’t have such a tool, but a socket with similar diameter as the seal should do the work. To be sure the seal is not driven to far down on the shaft, I hope that a washer of similar diameter underneath could be helpful.

I also would be happy to have any suggestions on how to clean up all fuel spill.

[fleetwin]

Did you try cleaning up those surfaces with fine “crocus cloth”?  You are in trouble if there is actual pitting in the area where the upper seal rides.

Keep in mind this engine probably has the very strangely designed recirculation system in that upper seal area.  What appears to be an upper seal leak might just be a messed up recirculation system.  This system has a vacuum port right next to the upper seal in the hopes of pulling out any excess fuel/oil collected in that area, this is then pulled back down into the intake manifold.

The problem with this system is that engineers removed the large oring that normally provides a seal between the upper bearing carrier and crankcase.   So, by deleting this oring, the engineers created an intentional fuel/oil leak, which to me more than defeats the benefits of the vacuum/recirc system.

The other issue with this system is that normal leakage is oftentimes misdiagnosed as a upper crank seal issue.

Does your crankcase look like it has been apart before?  If so, there is the chance that someone added the upper bearing oring that appeared to be “missing”.  This is a common mistake that I know I have made at least once as well.  The problem with adding the oring is that it prevents the recirc system from working (blocks the vacuum port).

I will never understand what the engineers thought they were accomplishing.  I could understand adding the vacuum port, but redesigning/repositioning the upper bearing oring so it could be used as well.

[Sputter]

I appreciate your post, the photos, and all of the responses.  Very informative.  I think you got sound advice.

1956 Johnson 15 Hp, FD-10
1958 Johnson 5.5 Hp, CD-15

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