1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

[08trdoffroad]

Hey all,

I recently purchased my first used outboard motor for my new to me 1981 13 ft Gregor H-34. It is a 1978 6 HP Evinrude 6804B.



I know very little about outboard motors but am hoping to learn (have a manual in the mail). I took the boat out for the first time this past weekend. The motor ran "fine" for the first half of the day. But it started acting up. It would "cut out" for lack of a better word and eventually would not throttle up past about a third throttle even with it at WOT, just bogged. After watching several youtube videos of motors very similar to mine, it also seems like even before the cutting out issue arose, it wasn't throttling up to similar RPM's as the ones I watched in the video.

Gas is fresh, and the previous owner stated they had recently gone through the carb.

What could be causing this?

Also, for the life of me, I can't figure out the tilt mechanism on the the motor. Can someone explain it too me. From looking at the mechanism up close. I swear there are two triangular pieces of metal that prevent the "pins" from being moved far enough out of their current position to another one. I feel stupid for having to ask this question, but I really need to be able to move the motor up one position...

TIA

 

[seakas]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Sounds like the carb to me.....go to this site and scroll down to the carburetor paragraph:
Johnson
Great site with lots of information...Leeroy has helped me many times.
For the tilt adjustment: There is a small lever on the front of the engine, called the reverse lock arm....usually labeled "Lock" and "Release". Put it in the release position. This will allow you to move the engine up. With the engine raised, move the tilting lever to the desired position. Move the engine back down and it will click back in place...Remember to put the reverse lock arm back in the "lock" position. Hope this helps.

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Thanks for the advice on the tilt mechanism. I will play with it when I get home from work tonight.

One thing I forgot to add during my original post is the primer bulb would not get firm. I could continuously pump the bulb and it sounded like it might be drawing in air. Even though the gas tank was more than half full.

I will wait for the manual to get here and then try to go through the carb just to rule it out. My next suspicion would be an issue with the gas tank/fuel lines...

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

I figured out the tilt mechanism and was able to move the motor up one position. Thanks again for the help! Once I figured it out, I felt even more stupid for having to ask about it!

I am going to start by rebuilding the fuel lines and replacing the gas tank. The tank and lines came with the motor so I have no idea how old they are, but there is some obvious damage to one of the connectors and the lines are not tight. I can pull them apart at the barbed fitting fairly easily even with the cinch straps installed.

Are tanks with gauges better or without? To me it kinda seems like having a gauge on it is just one more thing that can go wrong. I can lift up a 3 gallon tank and gauge the fuel level fairly easily...

If the new tank and lines don't resolve the issue I will dig into the carb. I am pretty certain it is a fuel delivery issue at this point. Hopefully it isn't the fuel pump...My manual came yesterday, so should I need to rebuild the carb, I am sure it will come in handy.

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

I haven't been able to mess with the motor much until today. I have been waiting for a water pump kit to come. It came yesterday and I was able to get the motor back together today. I cleaned the fuel filter and replaced a few clamps missing on the fuel pump and carb. The motor is still bogging down and dieing at full throttle. I have a new fuel tank and lines in the mail. I want to rule out fuel supply issues before digging into the carb.

Anyone have any other ideas as to things I can check before messing with the carb?

 

[Daviet]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

You can check your fuel pump by disconnecting the fuel line from the pump to the carb, pull the engine over and you should get spirts of fuel going to the carb.
When you overhaul the carb, make sure and remove the core plug on top of the carb and clean the passages in there. The high speed orifice is in the bottom of the bowel, behind the 7/16" drain plug, make sure it's clean.

 

[slate1234]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

changeing the coils might not be a bad idea, I had a 1978 6hp and a simler problem I changed the coils and cleaned the points, I found the coils were cracked on mine and caused a few problems, but as said above a good carb clean would also help

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Okay, this cheap motor is slowly becoming not so cheap. It seems like it could be a million different things, and with very little experience with outboards, I will probably end up just having to replace them...

One more thing I forgot to mention yesterday while tinkering with the motor. I had unplugged the spark plug wires while I fiddled with the fuel lines as a safety precaution. I forgot I had disconnected them and started the motor....it actually started, it wasn't until I noticed a different snappy sound to the motor that I realized I didn't have them connected and immediately killed the motor.

I can't imagine this is a normal condition...to be able to start the motor without the plug wires attached...

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Had the boat out on the water on Saturday. The cutting out issue is still present with the new tank and fuel lines. However I did a little bit of trouble shooting. When the motor would begin to cut out, I would start pumping the primer bulb (even though it was firm) if I continued to pump or lean on the primer bulb to force more fuel to the motor, the engine would pick up and run. This leads me to believe it is a fuel delivery issue, the two likely culprits are the fuel pump and carb. I ordered a fuel pump rebuild kit and carb rebuild kit just to rule them both out.

It is just odd to me that it will fire up and troll all day long, but has issues at anything more than about half throttle. My wife and I trolled a total of about 6 hrs without issue. On the way back in, I decided to tinker a bit more, if I slowly throttled up, the motor would run. If I punched it, it would cut out. Could the fuel pump be working intermittently?

 

[Daviet]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

The fuel pump might not be pumping enough volume of fuel for high speed operation, rebuild the pump and see if your problem goes away.

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Fuel pump rebuild kit came yesterday. Going to get it rebuilt today when I get home from work. Carb kit should come today. I will tackle that if the fuel pump rebuild doesn't resolve the issue. Hopefully I will be able to get the boat out on the water a few more times before the lakes ice up. We had our first measurable snowfall this morning down in the valleys, so it is already getting COLD up at the lakes I like to fish!

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Got the fuel pump rebuilt...it wasn't as difficult as I thought it would be, hardest part was getting everything lined up and back together to get the assembly bolts to thread back in without damaging any of the gaskets/diaphragms. I am picking up replacement fuel lines from the connector=>pump and pump=>carb. We'll see how it runs when I get home!

During the fuel pump rebuild, I found the smallest spring to be extremely gummed up with a jelly type substance, I am cautiously optimistic this could have been part of the problem.

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

I think I have resolved the issue. Pretty sure the fuel pump was the culprit. Ran it in my garbage can yesterday and it ran and accelerated strong, no cutting out.

Here is the video of the motor running! No more cutting out!

http://youtu.be/2HdOLmAP2Ng

 

[Xcusme]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Psst....It would be great NOT to have 2 posts with the same text running at the same time !!!! It just makes it harder trying to help you.

 

[08trdoffroad]

Re: 1978 6 hp Evinrude 6804b Cutting out & tilt mechanism ?'s

Sorry about that! I forgot I had the water pump thread when I posted here...removed the question from this thread. The cutting out issue appears to be resolved as of now which brings a conclusion to this thread!