NIB 57 7.5 Evinrude

[JohnRude]

I recently purchased a 57 7.5 Evinrude. The only mark on it is on the shift handle where it leaned against a wall or it’s box. The motor is pristine and appears to have never been in the water. There are no exhaust marks. No burn marks. The screw and bolt heads have never been touched. No marks on the prop. BUT!! The motor is seized tight. The mag will not turn. The tiller handle is seized and won’t turn even when disconnected from the mag advance arm. I can’t get the fly wheel off. I actually broke the fly wheel puller trying. The lower end seems free. Gear shift engages and prop responds accordingly.

It’s a mystery. Was this motor produced and not expected to run?

 

[dave-bernard]

most likely dried grease is the problem. I would not have thought the bronze prop would have been on that motor as NIB. aluminum would have been standard.

JMHO

1 user thanked author for this post.

fleetwin

[Bob Wight]

It looks like it may have been run at some time as some of the paint has burned off the exhaust cover, some paint is flaking around the head gasket and some paint has worn off the lower unit.  The throttle linkage does look all gummed up with dried grease.   Guess I would start with soaking the cylinders with some penetrating oil and try to get it freed up.   I would use a strap wrench to try turning the flywheel instead of using a breaker bar on the flywheel nut.    Also tap on the pistons with a wood dowel.

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1955 Johnson QD-16
1957 Evinrude Fastwin 18
1957 Evinrude 3022
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."

[crosbyman]

soak soak soak  the cyl. patience brings joy.

my 9.5hp  was the same…run perfect now after  alternately tapping the cyl  with a 1 inch dowel  sharp but no overly agressive  taps  alternating between cylinders.  took me  a week !!

keep soaking the  fw /crank shaft joint…  while working the cylinders.

then….try  some heat or  freezing the joint with  coolant  from  a keyboard spray can held upside down

try  a 1/4  inch  impact wrench on the harmonic puller      screw the bolts in enough not strip the FW

 

Joining AOMCI has priviledges 🙂

[Tubs]

The discoloration on the exhaust cover could be from the plug wires.
I found a Mark 7 that was really nice. Original paint but not as pristine
as Johnrude’s motor. Coils indicated it hadn’t been run in years. Tag
may indicate it was last run in 1959. When I took these plugs out they
had never been fired. They are J7J’s. Hard to find a crossover chart
that even list them today.
Tubs.

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

[aquasonic]

I agree with Tubs that the discoloration on the exhaust cover is just staining from the ignition wires, and the grease on the wires. The exhaust cover is water jacketed and won’t show signs of heat unless deprived of water. I’ve only seen one of these classic OMC 7.5 models that had burned paint on the exhaust cover, and that was caused by an impeller key failure.

This is clearly not a new out of the box motor. The gearcase has been off due to the paint loss on the four bolts. The cavitation plate is missing paint. The tilt bolt has had a 9/16 wrench on it for adjustment more than a couple of times. The carry handle also shows signs of wear.

I’m not sure if the blue has been touched up. Is there a different shade of blue on the underside of the tiller handle?

Regardless, this is still a very nice motor, and very much worth the effort to get it back to peak form.

 

 

Improvise-Adapt-Overcome

[frankr]

Possible theory??  Speed prop suggests use on a home-made hydro.  Boat flipped, and motor was put away wet. Hey, good guess, right?

[fleetwin]

OK, this will be the third time I’ve tried to reply to this thread….

In any event, that propeller did not come with this engine, so chances are good that the engine was run.  Frank poses an interesting theory, sure hope he is wrong though.  I keyed in on your comment about both the powerhead and the throttle being seized up, perhaps this is more than just coincidence.  Perhaps some came loose under the flywheel (hardware/busted coils) and had jammed the flywheel/mag plate.  Have you removed the little inspection cover on top of the flywheel and had a peek under there?

I suppose the recoil could be jammed, but that isn’t very likely.  Have you removed the recoil and tried moving the flywheel?  It is also possible that the gearcase is jammed up causing this issue, have you drained the gear lube?  Perhaps the rings are just lightly stuck, perhaps it will free up if you put a socket on the flywheel and try rocking the flywheel back and forth.  Please be careful, don’t crank down on the flywheel nut or use an impact gun on the flywheel nut.  Have you removed the plugs?  If so, do they look rusted?  Those intake bypass covers come off easily on the right side of the powerhead, which will allow a closer look at the piston rings/skirts.  Check to see if the rings are stuck in place.  Not a great idea to just run the engine with stuck rings, especially on a beautiful engine like this.

Let us know what you find…

[JohnRude]

Well, after reading the various suggestions I did further research. The marina where this all started changed hands about 15 years ago and this motor came with it. One guy said that he remembers it standing in a storage room when they took over. An original employee said he remembers that it was always just there. No one knows where it came from. The guy I bought it from said he was going to check the cylinders but the socket didn’t fit, hence the missing paint on a couple of bolts. Too much trouble. So it stood (and laid) for at least 30 years.

One members comments about seized or exploded coils caught my attention. I poured out the ATF that I had put into the plug holes and fired a bunch of penetrating oil up under the fly wheel. Over a couple of days I used an oak drift and tapped the fly wheel clockwise. It moved and finally freed up. The cylinders were not seized. I put the plugs back in and got good compression. Through the inspection port I can see that the coils are in pieces. The tiller handle is still seized and the mag plate won’t move. Will try to get the fly wheel off next. I have already destroyed one harmonic puller trying to it.

[Mumbles]

‘Will try to get the fly wheel off next. I have already destroyed one harmonic puller trying to it.’

Did you first remove the nut holding it on?

Sometimes this important step gets overlooked.

[Author]

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