1957 Evinrude 18hp Fastwin drive shaft spline issue

[1957Evin]

Hi all outboard enthusiasts! Thank you for all your help in advance and for all the help you have provided via this forum that has assisted with past projects.

This summer I acquired a 1957 Evinrude 18hp Fastwin. I gave it a test run and didn't have much trouble getting it to run, but it did run rough. The first thing I noticed was very little cooling water was being discharged when it idled. When I cranked the throttle up, the discharge water increased, but not to levels you would expect. The other interesting thing I noticed was although the engine ran at very high RPMs the power output was marginal. It was acting like the propeller was slipping.

I took the lower unit apart and checked the water pump and the drive shaft. The drive shaft was chipped. I disassembled the motor and fit the crank shaft together with the drive shaft and discovered they did not mesh very well and although I could not get them to slip, there was a lot of play.

Upon further investigation I discovered an O-ring was stuck inside where the drive shaft fits into the crankshaft. After removing the O-ring the drive shaft went further into the crankshaft and all play disappeared. They made a tight fit.

Do any of you think I need to replace the crank shaft and drive shaft since the drive shaft did get damaged a bit (there are noticeable chips on the outside of the splines)?

Thank you for your help!

 

[jbjennings]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

Some pics would be helpful!
But myself--if it seems to be holding good now and there's no play I wouldn't change them. But I'm far from what you'd call a mechanic. I'd check the compression on that motor although if it idles good it's probably fine. I'd also mark across the hub of the prop to see if it's slipping. If not slipping, then I'd wonder what pitch prop I had. I believe a 10hp prop might actually fit on it. Do you have a pic of the prop?
JBJ

 

[samo_ott]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I'd have no problem using it like that. Replace the O ring of course. I'm lazy and as long as it's fitting and working I'd leave it

 

[tmcalavy]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

Ditto...but if you're really concerned about the chipping on the shaft, post a wanted ad on the free classifieds at www.aomci.org
Someone there will have one for not much $$.

 

[1946Zephyr]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I would make sure you have a new o-ring on the top of the shaft and re-install it with plenty of lube, so it goes in freely. Your water pump may be on the way out, if your losing water flow at an idle. No biggie....these are inexpensive and simple to replace.

 

[1957Evin]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

Yes, pictures would help I will post some for you this evening. Thank you for your advice!

 

[mikesea]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

as I see it.the drive shaft will only go up as far as the mounting bolts will pull it,there usually is space at the top of crankshaft,its all in the machining,removing a stuck oring will not allow the driveshaft to go further up the splines to bite more material,your big problem may be the splines in the crank are stripped ,so the engine runs but doesnt really get a bite on the driveshaft so pumping fails and surely shifting will become non-existant,the crank splines rust worse than the shaft,different metal,Im sorry to say I bet the motor needs a new crankshaft

 

[freddyray21]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

as I see it.the drive shaft will only go up as far as the mounting bolts will pull it,there usually is space at the top of crankshaft,its all in the machining,removing a stuck oring will not allow the driveshaft to go further up the splines to bite more material,your big problem may be the splines in the crank are stripped ,so the engine runs but doesnt really get a bite on the driveshaft so pumping fails and surely shifting will become non-existant,the crank splines rust worse than the shaft,different metal,Im sorry to say I bet the motor needs a new crankshaft

doubt it needs a new crankshaft. My guess is when he pulled the drive shaft out the o ring stuck in there and when he tried to put it back in the o ring kept it from going in all the way. Once he got the o ring out it fit fine as it should. It's happened to me before. My guess is a new impeller will fix the low water output and may need a new pump housing as well. It sounds like you either have a spun hub or the motor is propped wrong. Depends on what boat you are pushing, but it should run out in the 20's if the right boat and prop.

 

[1957Evin]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I've finally found the time to take some pictures. Since my original question, I now have a few more questions too.

Lets start with the drive shaft spline: Here are two shots showing the damage. When I insert the drive shaft into the crankshaft, there is zero slop or play. They fit tight when fully inserted into each other. Will the lower unit hold the drive shaft tightly in place or will there be some amount of top to bottom movement that might allow the shaft to drop down a bit?

The next question has to do with the pistons. I wish I had done a pressure check before I disassembled everything, but I didn't. So now my question to all of you is, am I wasting my time with this motor? Take a look at the piston and tell me what you all think. This is the top piston and it is scored on the sides in a few places. The cylinders are fine - there are no scratches or marks, and the lower piston is perfect. Any thoughts?

Also, where can I find replacement emblems that look like this: Mine are obviously broken.

Someone asked about the prop - here are a few pictures of the prop - does it look like the correct one?

And lastly, since I have already stripped the paint off of every part to the motor, does anyone have the DuPont paint numbers for my 1957 Evinrude 18 hp Fastwin? If someone has the numbers I can buy the etching primer, filler primer, paint and hardener locally. The three colors I'm trying to match with the DuPont system are:
CHGY57 CHARCOAL GREY 1957-58
PCBL55 POLYCHROMATIC BLUE 1955-58
AQUA AQUA WHITE 1955-58

Again, thank you all for your help and I will keep you posted as to how things turn out. Oh, and I will soon have a few questions about putting the engine back together (as in what kind of sealant to use between the two crankcase halves).

 

[tashasdaddy]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

perfect matched paint is available here, http://www.nymarine.ca/colours.html
prop looks correct, a little filing on the edges won't hurt it. emblem like hens teeth, may find on ebay. imho, the top of the piston looks fine from what i can see, the rings ride on the cylinder, i would be tempted to use it. the drive shaft looks like old rust damage, from the oring on the shaft disintergrating, and allowing water to get there. if you do not have the OEM rude service manual, get one at outboardbooks.com

 

[samo_ott]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I would also use the piston if the cylinder was ok. Do you have a pic of the cylinders? I'd sand the piston a bit to try and clean it up. If you run your fingernail along the rings at a 45 degree angle does it peel a tad of your nail off? As in are the rings still sharp? They look it.

I assume you are also going to hone/de-glaze the cylinders when you have it all apart? That helps a lot I find.

Its too bad you did not take a compression check before you striped it though.

 

[jbjennings]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I've got little knowledge on those pistons and such. Just from my experience just noting how the pistons look in my motors that run well and the ones that had bad compression, however, I think that piston looks pretty rough. I'm suprised your cylinders don't have some scoring, myself. Not that it's not usuable, but it looks like there's been quite a bit of blow-by. Are you planning on new rings? Also, I would have liked to have turned the flywheel and felt the bearings on the rods and such while it was still together. Also taking the plugs out and using a screwdriver while the piston was right before TDC, and seeing if there is any play in the rod bearings or wrist pins by pushing down on the piston. Why did you decide to dismantle the powerhead? (just curious)
Myself, I'm thinking that a good used powerhead could be purchased for the price of a set of new rings, but I could be totally wrong. What's the word on the rod bearings and wrist pins and such? Are they nice and tight?

Maybe F-R will see your pics..... I'd be interested to hear his advice for my own benefit.:redface:

The prop looks right to me, also. It looks pretty bent up to me, though.

The drive shaft looks like corrosion to me, too. What about the powerhead side? Does it look o.k.? I probably wouldn't worry about the shaft--I think it would work. what does the drive shaft look like just below the water pump housing? Does it have a deep groove worn in it from the seal?

Those darned emblems are HARD to find. You can get a new one at Nymarine.ca, but they aren't painted and therefore worthless to me. I've bought them before and wasn't pleased with my paint job on 'em. They need chrome plating on the back to look nice.

Judging by the fact that you took it all apart that far and obviously want it to run absolutely perfect, I'd say you might be most pleased looking for a good used powerhead. But, maybe if the compression is the only problem, freshening this one up will work great. Hard to say unless you're looking at it all yourself. I'd be interested to see how cheap you can get rings for. Nymarine.ca sells them I believe. I recall them being pretty high.

Good luck,
JBJ

 

[steelespike]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I've finally found the time to take some pictures. Since my original question, I now have a few more questions too.

Lets start with the drive shaft spline: Here are two shots showing the damage. When I insert the drive shaft into the crankshaft, there is zero slop or play. They fit tight when fully inserted into each other. Will the lower unit hold the drive shaft tightly in place or will there be some amount of top to bottom movement that might allow the shaft to drop down a bit?

The next question has to do with the pistons. I wish I had done a pressure check before I disassembled everything, but I didn't. So now my question to all of you is, am I wasting my time with this motor? Take a look at the piston and tell me what you all think. This is the top piston and it is scored on the sides in a few places. The cylinders are fine - there are no scratches or marks, and the lower piston is perfect. Any thoughts?

Also, where can I find replacement emblems that look like this: Mine are obviously broken.

Someone asked about the prop - here are a few pictures of the prop - does it look like the correct one?

And lastly, since I have already stripped the paint off of every part to the motor, does anyone have the DuPont paint numbers for my 1957 Evinrude 18 hp Fastwin? If someone has the numbers I can buy the etching primer, filler primer, paint and hardener locally. The three colors I'm trying to match with the DuPont system are:
CHGY57 CHARCOAL GREY 1957-58
PCBL55 POLYCHROMATIC BLUE 1955-58
AQUA AQUA WHITE 1955-58

Again, thank you all for your help and I will keep you posted as to how things turn out. Oh, and I will soon have a few questions about putting the engine back together (as in what kind of sealant to use between the two crankcase halves).

Catalog lists standard prop at 9 1/4 X 11 you might want to check the diameter.If you choose to persue you might see if a prop,shop can refurb the prop or find a excellent replacement.

 

[mikesea]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I would be concerned with the crankshaft side ,again the crank splines will be worse than your driveshafft as I explained earlier,benn there done that,look at what your dealing with as far as the driveshaft,obviously there will be problems.As for the pistons.You can try getting some OMC engine tuner,soak the rings and piston in it and it will break down the carbon.Is there any original xhatching left in the cyl?looks like a bunch od x's scrathed into the cyl.if you didnt know.If they are still there ,you may do OK to hone a BIT and new rings with the old pistons.But The old rings may be ok and just de carbon and put the piston and its rings back in its orig cyl.I wish I could tell you after all this troubble you will boat happily.But,Ive been there in LARGER crank scenarios and needed to change crank.Perhaps im wrong about your case but id hate to see you do it all with a permanent neutral with no water pumping.If you can find ,and likely hard,change the crank if you have any doubt the splines are ???able/

 

[freddyray21]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

the piston does look a bit rough, but could be used. I too am curious as to why you pulled it apart without a compression check. The compression may have been fine. That shaft will work fine also.

 

[jbjennings]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I've been thinking about it and as bad as I hate to say it, here's what I'd probably do if money was a concern. (it always is, for me!)

I'd get a new water pump impeller for about 20 bucks, and a 10 cent o-ring from the hardware store for the shaft. Then I'd put it all back together after soaking and cleaning the piston as was said. then, you can run it and see if the clutch dog holds gear at wide open throttle, check compression, and see if there's any slack in the rod connections or bad bearings. You can also see how the driveshaft works but you should already be able to see if the drive shaft socket is corroded badly like Mikesea said it might be. I'll bet your compression may be fine. You might lightly hone the cylinders since you already have it apart. If the rings are sharp like Steve said they may be o.k.

After running it Wide open and all the tests, you'll know what you need to get it like you want it and how much it will cost you. Knowing this may get you off cheaper with a used powerhead and such versus fixing the one you have if the one you have is bad. The lower unit is just as likely to have bad parts as the power head.

You can use the old powerhad base gasket and use it as a pattern to cut one out of felpro black gasket material from the auto parts store if you don't want to wait on a new one.

How's your pressure tank, hose and hose connector o-rings? You said it ran rough....How's the spark (what width gap would it jump on the spark tester?) and did you clean the carb and gap/clean the points?
Then again, you may have all the tools to check the clearances on all of it while apart and fix it right!

Just some thoughts,
JBJ

 

[1957Evin]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

Thank you all for posting. You've each given plenty to think about. Almost all of you are curious as to why I took the whole thing apart.

A brief history: Back in the late 90's I found a 1956 5.5 hp Johnson Seahorse laying atop the garbage heap at a local landfill. It looked like new and I could not understand why anyone would toss such a nice looking motor. Well, I discovered it had a broken rod because the impeller pin broke or fell out or something and the engine got too hot (at least this is the best guess from the guys at Twin Cities Outboard). I bought a used rod to replace the broken one, put everything back together and it ran (still runs) like a champ. So there is the whole of my outboard motor repair experience until I acquired this Evinrude.

Knowing nothing about the importance of a compression check and wanting to have a little fun with my children, we dismantled the whole thing, labeled all the parts, took lots of pictures and stripped the paint off of all the painted parts since it had been repainted several times and looked horrible. Now we are looking forward to putting it back together.

I am willing to spend a little money on the motor, but this is mostly about education for the children. They are 12, 9 and 6. Each of them took turns unscrewing and unbolting parts off the motor after I loosened things for them. They had never seen the inside of a motor before, so they were very interested to see the inter-workings.

So, if all we accomplish is getting the motor back together and if it runs even just a little bit better than it did before we started, that would be enough for us. We don't need the motor, it is just an educational project.

So, that is part of why I would like to know if anyone has the DuPont paint numbers because I've got friends in the auto body world who can get me DuPont paint for much less money than what paint is selling for at nymarine. (and these friends know all about the etching primer, filler primer, paint and hardener). And if you don't have DuPont numbers, any ideas where I can get a close enough color sample for these paint guys to match?

So if you can help me in the bare minimum of cost department to get this motor running so the kids can feel a sense of accomplishment, I would really appreciate your help. I will answer more of your questions when I get a chance (Probably Friday). Thanks again!

 

[F_R]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

Considering you're just doing it for a fun goal, go ahead and put it back together. You will wind up with what you had before you took it apart. Seems like a lot of work for something that might not be a satisfying result though. However if you are wanting to fix it, the piston is toast. The piston skirt acts like a valve, preventing exhaust gasses from blowing into the crankcase. That messed up piston won't do a good job of that and will get worse.

And the crankshaft is suffering from severe rust damage to the splines. How bad, we cannot tell. Your slippage problem probably was the prop hub. As a general rule, splines hold or they don't hold. Once they strip, it's all over. Somebody pointed out that the assembled height into the crank cannot be changed. He's right.

The guys over at the Antique Outboard Motor Club have a list of rattle-can paints that are a close but not correct match. Good enough if you don't know what they originally looked like. www.aomci.org

You probably can find what you need for replacement parts there too. Post a free want ad on their Webvertize classified ads page. Don't expect to find that emblem, they are rare and worth their weight in gold. I might have a piston.

 

[1946Zephyr]

Re: 1957 Evinrude 18hp Fastwin drive shaft spline issue

I've finally found the time to take some pictures. Since my original question, I now have a few more questions too.

Lets start with the drive shaft spline: Here are two shots showing the damage. When I insert the drive shaft into the crankshaft, there is zero slop or play. They fit tight when fully inserted into each other. Will the lower unit hold the drive shaft tightly in place or will there be some amount of top to bottom movement that might allow the shaft to drop down a bit?

The drive shaft looks a bit hashed, but if you re-install the o-ring with plenty of lube on it, it should work out fine. The o-ring will help keep the driveshaft centered, up inside the crank.

The next question has to do with the pistons. I wish I had done a pressure check before I disassembled everything, but I didn't. So now my question to all of you is, am I wasting my time with this motor? Take a look at the piston and tell me what you all think. This is the top piston and it is scored on the sides in a few places. The cylinders are fine - there are no scratches or marks, and the lower piston is perfect. Any thoughts?

Well, the piston looks scored pretty bad. If it was me, I wouldn't use it. If you're planning to do a restoration, I would go ahead and replace it with one that is in equal condition to the other one. You could easily find replacements here, through one of the other members. Scoring of this nature, is usually caused by overheating, coupled with a lack of oil. I've heard it is also caused by bad fuel, but I don't buy it. Hone the cylinders out and make sure there is no scoring in them.

Also, where can I find replacement emblems that look like this: Mine are obviously broken.

Clean that emblem up really good and super glue it. If you make sure that you clean the break really good and match them together perfectly, then you should be fine. Gently wipe exess glue from the outside with a rag.

Someone asked about the prop - here are a few pictures of the prop - does it look like the correct one?

Your prop looks fine. It wouldn't hurt to clean it up, but it looks okay.

And lastly, since I have already stripped the paint off of every part to the motor, does anyone have the DuPont paint numbers for my 1957 Evinrude 18 hp Fastwin? If someone has the numbers I can buy the etching primer, filler primer, paint and hardener locally. The three colors I'm trying to match with the DuPont system are:
CHGY57 CHARCOAL GREY 1957-58
PCBL55 POLYCHROMATIC BLUE 1955-58
AQUA AQUA WHITE 1955-58

Again, thank you all for your help and I will keep you posted as to how things turn out. Oh, and I will soon have a few questions about putting the engine back together (as in what kind of sealant to use between the two crankcase halves).

I think you could get some advice through Seaway Marine, up in Seattle Washington. They could have the paint on hand. Also, use the Zinc Chromate primer once you have it stripped down. That is the base coat that these motors are prepped with. It almost looks like the old Johnson green when applied.
As far as the crank case halves go, you can buy the sealant at your local marine parts dealor. Most any good gasket sealer will work though.

I hope you have fun with that, I have a 1953 Johnson 25 hp to strip down and restore.

Leon