Logo
FULL SITE MENU

evinrude 6hp 1978 throttle stuck

J

jan2021

New member
I bought a faulty Evinrude 6hp 1978 outboard motor, the seller said there was no spark at the spark plugs but I noticed that the throttle grip would not move.The throttle grip is completely stuck.Can you tell me where to start troubleshooting?The engine number is B68B66.
IMG_2605 a.jpg
 
Yes that is a nice motor have one of the best fishing motors ever made. What is that little plug/cap on the port side? Was something added to the motor that is disrupting the throttle movement? I'm not sure if an alternator or charging option was available on that motor. Historically the grease inside the twist grip can gum up and it has to be removed and fully cleaned and re-lubricated with fresh high quality grease. Since the twist grip is spring loaded, before removing that phillips screw you have to push straight back on the twist grip to relieve the pressure on the spring otherwise the threads on the little phillips and/or the stem/shaft will get buggered up. So in other words you have to maintain pressure pushing the twist grip towards the rear of the motor as you remove the screw, then reverse procedure when reinstall. Once the twist grip is off you should slide off the collar with the start shift and fast graphics. Underneath the collar are too flat head cap screws, (normally slotted), which often work loose so you should make sure they are tight. Also the larger slotted screw in the tiller arm itself has to be nice and tight in order to hold things from getting messed up. When you install that little throttle information sleeve make sure that it is bent in such a way that it will grip tightly again on the tiller handle and not stick up and grab the twist grip causing problems. I got so many of these little motors where that information sleeve/collar has bound up underneath the twist grip and then the twist grip is forced and cracked. 🥺
You are a wise fellow to ask first before destroying things. You came to the right place here. Between Racer and a handful of other technicians here you are tapping into a thousand cumulative years of experience. 😊
Its these older brilliant engineered motors that keeps techs such as myself and those still on board, very happy to help out. Little details like those I have expressed here are critical to make things easy and preserve longevity in this wonderful fishing motor.
A compression test would be a good idea and also examine to see if there is evidence of a new head gasket. Lack of spark on this motor is usually just oxidation on the points as they have a silver coating which acts as a great conductor but also can of course become oxidized from moisture and non-use. Some may correct me but I think the cracked coil problem was corrected by your model year. However, take note that the improved coating was not always "forever" either....also could crack and I've seen the coils arc out underneath to the stator plate through the crack. We have covered coil installation and points installation many times, so done correctly....you will have decades of trouble-free operation.
 
Last edited:
That fitting on the side is the ----AC lighting -----To run lights on the boat.-----Factory installed on many models !-----And there are no points on the 77 / 78 / 79 models !
 
Last edited:
Yes, what am I thinking. The full CDI was introduced to the six horsepower in '77. I'm gonna have to refill my brain function medication. I've only seen a couple alternators on these models. I thought them to be pretty rare, but a really handy device to keep your sonar charged if you added a rectifier and a regulator too.
 
timguy said:
Yes that is a nice motor have one of the best fishing motors ever made. What is that little plug/cap on the port side? Was something added to the motor that is disrupting the throttle movement? I'm not sure if an alternator or charging option was available on that motor. Historically the grease inside the twist grip can gum up and it has to be removed and fully cleaned and re-lubricated with fresh high quality grease. Since the twist grip is spring loaded, before removing that phillips screw you have to push straight back on the twist grip to relieve the pressure on the spring otherwise the threads on the little phillips and/or the stem/shaft will get buggered up. So in other words you have to maintain pressure pushing the twist grip towards the rear of the motor as you remove the screw, then reverse procedure when reinstall. Once the twist grip is off you should slide off the collar with the start shift and fast graphics. Underneath the collar are too flat head cap screws, (normally slotted), which often work loose so you should make sure they are tight. Also the larger slotted screw in the tiller arm itself has to be nice and tight in order to hold things from getting messed up. When you install that little throttle information sleeve make sure that it is bent in such a way that it will grip tightly again on the tiller handle and not stick up and grab the twist grip causing problems. I got so many of these little motors where that information sleeve/collar has bound up underneath the twist grip and then the twist grip is forced and cracked. 🥺
You are a wise fellow to ask first before destroying things. You came to the right place here. Between Racer and a handful of other technicians here you are tapping into a thousand cumulative years of experience. 😊
Its these older brilliant engineered motors that keeps techs such as myself and those still on board, very happy to help out. Little details like those I have expressed here are critical to make things easy and preserve longevity in this wonderful fishing motor.
A compression test would be a good idea and also examine to see if there is evidence of a new head gasket. Lack of spark on this motor is usually just oxidation on the points as they have a silver coating which acts as a great conductor but also can of course become oxidized from moisture and non-use. Some may correct me but I think the cracked coil problem was corrected by your model year. However, take note that the improved coating was not always "forever" either....also could crack and I've seen the coils arc out underneath to the stator plate through the crack. We have covered coil installation and points installation many times, so done correctly....you will have decades of trouble-free operation.
Click to expand...
I bought this Evinrude motor on 27.6.2025 for 40 euros:)On Friday 4.7.2025 I will get to explore the motor more.I also have an Evinrude 4 hp 1983 outboard motor that I replaced with a new water pump impeller and outboard oils.And there is another Evinrude 4hp 1983 spare outboard motor and a Johnson 4hp which is probably also an outboard motor from the 1980s.
 
Remove the cover.------Find the clip at the top of the tower shaft.-----Remove the clip.-----Now you can determine if the handle is stuck .----Or the magneto plate is stuck.----A simple process.
 
I have a tube of the old 2-4-C, but any light grease in the twist handle is good. Your local John Deere dealer sells gunnable tubes of what they call water resistant grease,(blue color), for about $5. That will last dozens of motors dozens of years, I use it to lube any of the fittings requiring a grease.
For the lower end gears pump in 75-90 gear oil
 
Thousands of gallons of perfectly good gear oil is thrown out each year. There is no reason to toss oil that only saw 20 maybe hours, if it isn’t water contaminated.
With a new to you motor, check the oil for water after a few hours. If it’s milky, re-seal the gearcase.
Build a little stand to hang your motor at season end, (if your area gets freezing weather). Last use, open the oil drain plug slowly.
If oil is milky, you’re getting water in…drain it, & re-seal gearcase
If you leave the motor standing for a few days, the water will separate & sink. When openening the drain screw, if water comes out drain it, then have the bottom end re-sealed. If water is left in to freeze it will crack the case, or otherwise wreck the leg.
If the oil is clean, there is no reason to throw it out.
 
Back
Top