'55 Evinrude 25 hp, more problems

[crocket15]

I have a 55 Evinrude 25 hp, the serial number is 25920 - 25230. Now i've heard that there was a point during this year when a seal was made poorly allowing water to get into the motor. I was wondering if my motor fits that bill. The situation that brought me to this question is that I found water on my top spark plug when I was checking my motor and creamy wet gas was also coming from my exhaust.

Initially my problems started when I took the boat out today, made it about a 1/2-mile before the engine lost nearly all power. I don't know if it dropped a cylinder or if it overheated. the head was pretty hot, I could touch it but couldn't hold it and be comfortable. It may have been running lean. After taking the carb apart the low speed intake in the carb had been completely plugged by gunk that I believe was from old worn out fuel lines. I replaced these today.

After replacing crusty hard fuel lines and cleaning out the carb, my motor would still not start. It had ran well two days ago with little to no resistance - (only me in the boat - no tubers or added weight). today, as i was pulling a buddy on a knee-board which I've done often, it decided to cut power and run with no throttle.

As far as overheating by way of a bad impeller, I replaced the impeller last summer, however I didn't have the tools to replace the seal just below the impeller at the time. I was wondering if this is this seal that is bad news? I know I have to replace the LU seals anyway because I am getting water in the LU. If this is not the (powerhead?) seal that was practically a defect from the start, which one is? Also, if I'm pumping water to places other than where it is supposed to go, can less water cause overheating?

I think my initial problem could have been a lean running motor that overheated. But with my motor not starting while it's cool, with a clean carb and it apparently getting gas, I think my spark plugs may not be the right ones. They are Champion and seemed to look similar to the ones that were in the motor when I pulled the old ones out two years ago. What are the proper Champion plugs for my motor? and if I already have the right ones, could these go bad in two years and cause my problem of not starting now? My motor ran for a long time on these plugs. Even if they are the wrong plugs, what would cause them to all of a sudden fail now?

I feel like it might be in my best interest to replace the head gasket. I have looked at my coils through the flywheel and everything in there seems pristine and clean. The only thing that seems poor would be the seals on my carb, LU, and the plug wires are quite old. Like I said before, two days ago she ran just fine, today that isn't the story. Plug wires working periodically? Spark Plugs finally kicking it? Fuel, too much or too little?

I would at least like to get it running again and deal with the overheating problem if it persists with the clean carb. Right now it will fire with a squirt of gas or about every 20th pull. Even then it only fires once or twice.

She's a nice motor, as of recent she's just had a few of those days.

 

[jbjennings]

Re: '55 Evinrude 25 hp, more problems

I'm no expert on the '55 model but if you have water in the top cylinder, you definitely should pull the head and see if you can see if it's a head gasket leak. New head gasket is in order either way if you remove the head. The seal under your water pump wouldn't cause water in the powerhead but the lower crankshaft seal might. I would think that even a bad lower crankshaft seal would cause the bottom cylinder to get water in it and not the top, but like I said, I've never worked on a '55. I'd still get a spark tester and see if both plug wires have enough spark to jump a 1/4 inch air gap. Seems obvious, though, if you've got water on your top spark plug, that you're dropping a cylinder due to water intrusion. I'd start with the head gasket. It'll never run right until you fix the water in the cylinder problem.
Good luck,
JBJ

 

[crocket15]

Re: '55 Evinrude 25 hp, more problems

I replaced the spark plugs. the sad thing is that i was running champion j8c's before. What kind of damage could these have done to my motor over time?

i'm also getting very little compression from my top cylinder, i do not have a compression checker, but it is obvious when i remove the top plug that pulling the cord is just as hard, when i remove the bottom plug, i it turns way too easy i believe.

Could the water that i had on the top plug when i removed it, and the bad compression be from a head gasket? What else could cause both of those things to happen?

I am also replacing the plug wires. The coils and points look good, but could they be bad anyways. Getting the flywheel off wasn't bad at all. so i'm willing to leave the ignition parts alone for now and see if new wires will fix the problem. If i get spark back in the top cylinder, will that possibly get my compression back?

I've also heard that exhaust gaskets can cause problems. Could this cause the water and low compression? or is it probably a combination of both exhaust and head gaskets?

I've posted pictures of my coils, points and the outside view of my gaskets.
the coils were spotless until I touched them with greasy hands.

 

[jbjennings]

Re: '55 Evinrude 25 hp, more problems

Yes, I believe that head gaskets could be the cause of both your low compression and water intrusion problems. Bad exhaust gaskets can also let water into the cylinder via the exhaust ports. If it were me, I'd take off the head and take a peek at the cylinder walls and such, to see if I thought it was worth the time to try and fix it. If the cylinder walls are gouged up it may not be worth putting money and time into it.
Good luck.........Maybe Wayne or Steve or F-R can give you some expert insight into this exact motor since I haven't worked on this model. I've fooled with a '53 and '54, but not a '55 yet.
JBJ

 

[jbjennings]

Re: '55 Evinrude 25 hp, more problems

BTW,
Your coils are newer ones and probably o.k., the head gasket LOOKS perfectly normal but that doesn't mean a thing, it's what's happening inside that counts. The port side of the head looks good, but the starboard side looks like it might be a little discolored. The discoloration COULD be a sign of an overheat which could have warped the head slightly and caused a bad seal on the top cylinder, or it could have caused a similar problem with the exhaust gaskets. Bite the bullet and pull the head. First, however, I'd check the compression with a gauge. At the very least, it'd give you something to compare to when you put a new head gasket on to see if that were the probelm. You need to put your cylinder head on a piece of glass to see if it's actually flat. If not, a little figure 8 sanding will flatten it. Put your sandpaper on a flat piece of glass and move your head over it in a figure 8 pattern.
Good luck,
JBJ

 

[crocket15]

Re: '55 Evinrude 25 hp, more problems

It's the head gasket. Sure enough the top ring was cracked pretty good and the gasket frayed where the water flows. The inside of the cylinders look good, smooth and clean. Just waiting on UPS now.

Could this have been from running too hot of spark plugs - J8C's? If not, what else might have caused the gasket to bust now, and not in the last year and a half that I've been running the J8C's? Possibly the combination of an even hotter burn with a lean mix from a gunked up carb?

 

[crocket15]

Re: '55 Evinrude 25 hp, more problems

Does anyone know the torque specs to a 1955 evinrude 25hp? what is the order in which you tighten the bolts?

 

[R.Johnson]

Re: '55 Evinrude 25 hp, more problems

96-120 in/lbs, Start in the middle, and work out in a figure 8 pattern. We're talking a 54 year old engine here. All new seals would'nt hurt a thing.

 

[crocket15]

Re: '55 Evinrude 25 hp, more problems

thanks, all news seals is pretty much what she's getting, that and a week's worth of attention.