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78 6 hp evinrude power loss

B

braden

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"I just got a new 1978 6hp evi

"I just got a new 1978 6hp evinrude. We put new plugs in it & the first day it ran for an hour pretty well. Second day it would not even start . I got a used fuel pump from a local dealer ( he was out of new ones & just wanted to help) After installing it the motor ran great in the tank for about 20 mins. at both idle & high rpm. Next day my son tried it out in the river - Started fine (2 pulls)- ran at low speed for a while- when he went wide open it would only run for about 1 to 2 mins. before starting to lose power. He was able to keep it running by a combination of feathering the throtle & manipulating the choke , otherwise it would die out. He was able to start it right back up & it would run at low speed all day but same power lose at high speed after a min. or so.
Would you recomend I buy a NEW fuel pump,rebuild the carb.or is this maybe a fuel tank pickup problem I have been reading about in other threads ? I just need a starting place & any help would be greatly appreciated.
PS: I did clean the filter in the used fuel pump before installing it."
 
"Personally would remove the c

"Personally would remove the carb and clean it out. Then would put a new water pump in it just so I know it is working. Then would replace the fuel line from the connector to the fuel pump with clear plastic so I could see any air leaks.

If pumping the primer during failure, didn't help (or hurt). I would say the fuel pump is not the issue"
 
Thanks for the reply Bill. I&#

Thanks for the reply Bill. I'll order a carb kit & try that then.
I will let you know how it goes.
 
Took a while but carb is rebui

Took a while but carb is rebuilt & cleaned & is now reinstalled. Ran it in the tank for about 1/2 hr. It seems to not lose power after a couple minutes now but hard to say since I can't really run full throtle without fear of parts flying.
Will try to get it in the river this weekend for a good test. let you know. Thanks for the help!
 
"(Carburetor Adjustment -

"(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note 1: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

Note 2: If the engine should be a three (3) cylinder engine with three (3) carburetors, start the adjustment sequence with the center carburetor.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
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