1958 Evinrude 7-1/2 Fleetwin carburetor overhaul

khe

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I have a 24:1 fuel mixture in the tank. The owner's manual recommends 16:1 but that was with SAE-30 engine oil which was all that was available in the late 1950s. The dealer told me with the modern oil, I could run 32:1 and even up to 40:1 but I'd never run it that lean.

I had it all set to dial in the carburetor Saturday afternoon. It was 68° and I had it all set up on a boat. I started it up, it died after a 10 seconds and I restarted it, revved it up and it stalled again. When I attempted to restart it, the recoil hung up and the rope wouldn't retract...

I am going to take apart the recoil soon and fix that but the carburetor adjustments will most likely need to wait until spring. Another option would be to have the local Evinrude dealer dial it in in his test tank - I may see what he'd charge for that.
 

khe

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The recoil spring wasn't broken but the problem was the spring was not formed in smooth concentric circles, it appeared to be kinked in several spots which would explain why the rope was hanging up. I'm not sure how the spring would have been damaged like that. The 62 year old grease was like putty so I cleaned all the recoil components. Time for a new recoil spring and fresh grease.
 

khe

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The recoil starter is all fixed. When I picked up the part at the dealer, I showed him the old spring and he said all the kinks are usually caused when the rope breaks and the recoil spins out of control.

I bought a new spring and a length of starter rope and have the recoil all fixed.

The dealer said he'd only charge me $20 to dial it in in his test tank as long as all he had to do was dial in the carb. I'd rather do it myself but I thought it was a fair price.

I want to run it one more time in the barrel before prepping it for winter. Last time, it didn't want to run very long and I found the fuel hose connections were leaking so the tank couldn't maintain pressure. I fixed that and also noticed that when I tightened the high speed adjuster knob screw, the needle moved. Knowing that, it is possible the high seed jet was not in the one turn open set-up position.
 

khe

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This project has been on the back burner for quite some time. I was going to start a new thread but since I was the original poster, I figured I'd just add to the existing content.

I could not get the motor to run more than a few minutes before it died and would not restart. I elevated the fuel tank on a step ladder to rule out a fuel feed problem. I then checked for spark - no spark was present. Since it was in the fall, I drained the water and carburetor, sprayed fogging oil in the cylinders and put the motor away.

I knew there was something wrong with the ignition since it had spark when cold but not after it ran. I pulled the flywheel last night and immediately discovered what was wrong - the coils were all cracked and arced. I ordered points, condensers, coils and plug wires. I bet the coils are original to the motor.

The strange part is the points in the upper left of the photo were so out of adjustment that they did not even open or if they did, it was nowhere close to .020"
 

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racerone

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This is so common !----Every one of these magnetos installed in the 50's / 60's / 70's has suffered the same fate.------The points and condensers have been replaced already.
 

khe

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I think the coils may be original or replaced once. The motor was my father-in-law's and he bought it in the early 1960's and it hasn't been used since 1980. He passed away four years ago and that's how I wound up with it.

Cosmetically, it is in great shape and it is soon to be back in operation.
 

Crosbyman

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lucky man... cracked coils === >low usage usually :)

with new coils ...cleaned points and probably new condensers you should be good to go .. great motors btw. btw.... hard to see if you have a oiler felt in place

easy to convert to pump if you have no tank or leaky tank

 

racerone

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The 7.5 HP like that was only marketed for 3 years.----Last in 58.----They are a sweet running engine if everything is in good shape.----It needs a new water pump impeller before launching the boat.----Most old time " Evinrude / BRP " shops would have it in stock !
 

khe

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lucky man... cracked coils === >low usage usually :)

with new coils ...cleaned points and probably new condensers you should be good to go .. great motors btw. btw.... hard to see if you have a oiler felt in place

easy to convert to pump if you have no tank or leaky tank

It's getting new points, condensers, coils and plug wires.

I couldn't see if it had the oiler pad either. One comes with the tune up kit.

I have the four gallon pressurized tank - it's in very nice condition and doesn't leak.
 

khe

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The 7.5 HP like that was only marketed for 3 years.----Last in 58.----They are a sweet running engine if everything is in good shape.----It needs a new water pump impeller before launching the boat.----Most old time " Evinrude / BRP " shops would have it in stock !
My grandfather had a 1954 Evinrude 7-1/2. I'm not sure how many years prior the 7-1/2 was available.

I replaced the water pump impeller right after I got it running two years ago as it was not pumping water. One of the impeller blades was broken off.
 

racerone

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The 1954 was a 7.5 hp I agree.----But the 1958 like yours was marketed in 56 / 57 / 58.----Some parts ( ignition ) were the same in 54 .----If your were looking for many of the parts you would want a 56 / 57 / 58 parts motor.
 
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khe

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The coils, points, condensers, etc. arrived today so I began disassembling the components from the magneto plate. The oil wiper was disintegrated but a new one came with the points. I got the magneto plate all cleaned up and tested the upper crank seal. I sprayed WD-40 over the seal and before I could grab the wrench to turn the flywheel, all the WD-40 leaked into the crankcase so it looks like I need an upper seal.

The seal is not like the the rubber molded seal R&R's I have seen in some of the videos. It is a metal piece that rotates with the crankshaft. Possibly a carbon seal below? I'm not sure.

The retaining plate has four tapped holes - two of the holes use a crew directly from the magneto plate and the other two use the long screws from the coil so there are four attachment points. What does the notch in the 5:30 position in the photo need to be positioned? I can't see anything that interfaces with it and the plate got moved during removal of the magneto plate.
 

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racerone

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There is no oil seal , rubber or carbon.----Just a slinger.----Do not worry about the notch.
 

khe

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There is no oil seal , rubber or carbon.----Just a slinger.----Do not worry about the notch.
Sounds good. Thanks for the information!

I need to purchase secondary ignition wires as the originals were stiff as a board and all arced up where they attached to the coils. I plan on buying that from the local dealer tomorrow and should be able to get it back together and hopefully dial in the carb. this weekend.

In the past, I have run the unit using my 96 gallon trash can ad a test barrel. I'm wondering if that is large enough to dial in the carb. or will the prop push all the water out when revved up?
 

Crosbyman

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just remove the prop... do not adjust the high speed in a barrel...even more so without a prop
 

Crosbyman

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not if you just idle it... bucket tuning won't allow you to adjust things perfectly... just get it running then use a lake to finish up on adjustmenets
 
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