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1971 Evinrude 6hp Project

Edchris177

Regular Contributor
I picked up this little 6hp for the cost of a couple 6packs of good beer.
Had no idea if it ran, but I could use some of the parts.
Racerone advised to spend NO money on a 50 year old motor til I’d ascertained it’s bones, so with his mentoring I put my limited Outboard knowledge to work.
Compression was 85psi, both sides, I’ve been told 80 is fine for these motors


The starter slow to retract, but I found the plastic pinion gear on top was mashed up & binding the flywheel.
A few minutes with an Exacto knife made it workable, but I’ll change it.

Was getting intermittent spark in one cylinder. Changed out top plug wire, as it showed very high resistance.
Made a new one using some spare wire cored ignition cable from an ancient John Deere lawn tractor- (serial #87).



Pulled flywheel, coils were new, points looked good, cleaned them anyway.
Set points to .020 as a starting point, then timed it as per Racers instructions, (by using an ohmmeter, & just lifting off the flywheel to adjust points so they opened when the flywheel mark was centered between the two marks on the stator plate). No need to buy the timing tool.

Discovered one condenser was bad, borrowed one from an old motor, & now have good spark on both jugs.
Carb was full of grunge, suspect old fuel left in. Disassembled & cleaned everything, used the old gaskets for now, found a couple packing washes from a previous carb job that didn’t need them.
It didn’t start well, needed a shot down the carb throat, but ran intermittently once going.
Here I made a mistake. Thinking it was a bad fuel pump, (it would “usually” run if I pumped the primer), I pulled the line from the pump to the carb, then pulled the starter- it spit good pulses of fuel, leading me to believe the fuel pump was OK.
I changed the fuel lines as they were rock hard, & loose in the barbs.
Today, I pulled the fuel line off the carb, & gave it a suck/blow test. I can easily blow air in both directions through the pump, idiot, I should have done this earlier.
Swapped a pump I scavenged off a scrapped motor, Weather warmed up today, so I put it in a barrel- Buenos! It started, & seems to run OK.
I left it for half an hour & it just chugged away.
Using a mechanic stethoscope all around, I don’t hear any knocking, or other unhappy noise.
Seems my 50 year old timing light doesn’t work, not sure if it can be rebulbed, so I could check exact timing.
It runs cold as I pulled the thermostat- it was stuck closed.
So far I have $30 into it, I’m leaning to buying the required parts, & make it into a fishing motor.
https://youtu.be/x_vJL2NK1gA
 
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Hi Ed, great job. Enjoy your description. Excellent compression. These are the greatest motors ever made. I still run my very first Fisherman Six, Dad bought for me to guide with in 1965. I swear that it has nearly 3500 hours on it. It is behind me in my avatar from about 1976. Used a Merc Mark 30 for high speed, then the Fisherman for trolling....mostly Lake Trout, NW Ontario. The fellow in the picture worked as an underground miner for iron ore in the 1920's and 1930's in Hibbing MN. A mountain of a man, later moved to D8 cable operated Cat, retiring in 1964....what a fisherman!
I look for these motors constantly, fix them up to perfection, then often ship throughout the country. Recently sold one to a fellow in Hawaii. He absolutely loves it. I have used, and recommend Amsoil 100:1 2 stroke pre-mix, but mixed at 2 oz per gallon. Amsoil Saber is a bit newer oil and can be mixed safely at 80:1 or even 100:1. It is engineered for air cooled, but can be used for water cooled too....more expensive, however, than the 100:1 pre-mix. I consider myself a pretty decent mechanic, with adequate experience on these motors. I have to say that the head gasket should be replaced, if it hasn't already. The OEM gasket can fail after 40 or 50 years by slowly burning across a passage between the cylinders. This happens over time and quite common. The Sierra gasket is improved design and materials. Be sure to surface the head using 180 grit wet or dry paper, a nice flat surface, and lubricate with soapy water.
My 1965 Evinrude Fisherman will certainly outlast me....unless maybe I live as long and healthy as Joe Reeves, or Racer.
 
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Today I dropped the gear case. When running in a trash can I noticed no water would drain out the small hole down below the cavitation plate. The entire cavity that feeds that hole was full of crap. Tried compressed air via the drain hole, no bueno.
Tried a long screwdriver, but couldn’t get it all, so I built a little roto-rooter using a cordless drill & a piece of SS flat, from an old wiper blade. That got almost all, & air the rest.
I’ve been advised the original metal impeller housing get worn & grooved, so I took that apart. Does it look OK to re-use, or should I get the new plastic housing?
I noticed there were no gaskets above, or below the SS plate the impeller rides on. The parts diagram shows only one gasket, below the impeller base.
Watching a couple of videos, one showing the original metal housing, had no gaskets. One showing the new plastic housing, they placed a gasket on top of the SS plate.(can’t figure out how to delete the 2nd photo).
What is the proper assembly, do only the newer plastic housings use a gasket, or did that guy do it wrong?
I noticed the new SS plate is slightly different from the original. The new has a bigger hole, (near the word UP), & it’s in a different location than the original. I also see a little raised tab, which appears to match a cutout on the supplied gasket. If using the new plastic housing, does this gasket go below/above the SS plate, or below the driveshaft housing plate?
cant figure out how to delete 2nd photo.
 

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Looks like you are trying to use a mix of old and new style pumps.
 

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Ahhh, that makes total sense now, thank you. I didn’t look at parts diagrams newer than 1976.
A local chap bought the newer kit while he was in the USA, dealer told him it would fit his motor, which it didn’t. (His is a 1955 I believe).
The kit was of no use to him, so I bought it cheap, as I knew from the part# on the original OMC box, it would fit the 70’s motors.
Looking at gasket #51, it says 2 Required for Assembly. Where does the 2nd one go, the diagram only shows one, on top of the impeller housing plate.
There was only one in the complete kit I picked up. Part #763758
 
That kit only needs 1 gasket !!!-----And that complete kit will fit a 1955 model 5 1/2 HP.----This stuff is so easy to me.
 
ask me if you need any parts... bought out an entire dealership that closed! One thing to test: pull out choke and quickly push it back in again at idle. if it picks up speed, the cam roller/tab arm is too far away from the throttle cam. these arent designed to run with the throttle plate completely closed at idle (no calibration holes in throttle plate in carb). once cam adjustments are made using a 5/16 wrench, it will idle down much lower without running lean. notice most (not until CD ignition last 2 years of production) dont have a stop switch hence the uncalibrated throttle plate so it shuts itself down easier.
 
CD ignition was availabe in 77 , 78 , 79 so that makes 3 years and not 2 as posted in #8-----Throttle plate # seems to be the same from 65 to 79 models.
 
Have to concur with fdrgator on this one.-----Just looked at a carburetor off a 1978 model.-----The throttle plate has 2 wee holes at the top and a cut off at the bottom.-----This would allow a calibrated amount of air in at idle !!
 
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i stand corrected about calibration... but not about making sure throttle cam is adjusted properly. And yes racer, I was off 12 months about the CD ignition thanks for pointing that out.
 
Sorry guys, I can’t look at my motor…I’m down in the Caribbean for a couple weeks. It ain’t all gravy, the beer is ****ty Presidente, but at least it’s ice cold.
I was looking at my emergency generator the other day. It doesn’t have any holes in the butterfly, but it does have a small cutout on the bottom, I think all small motors have to have some way to allow air at idle.
My understanding, (from the 1975 owners manual), of the 6HP, states that when the throttle is turned fully to the id,e position, it grounds out the ignition. The manual states that how the motor is stopped.
Revenge, thanks for the offer of parts, but I’m up in Canada, & shipping can be a pain. Racer has most of the parts I ever need…& he can install them if required!
 
I just looked at a ‘71 Evinrude 6hp that I’m working on. It definitely has a hole in the throttle plate. So does the ‘74 I have.
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