Mariner 8hp lose power on full throttle

It's been a while since I was here, but to see the news that "You last visited: December 31st, 1969" was a surprise!
I'm sure I've been here since then!!!

Anyway....

Mariner 8hp, starts first or second pull every time. Ticks over fine, runs up to about a third or half throttle OK. Wind the throttle open and she roars away for a couple of seconds before coughing and struggling to keep running, close the throttle to half or less and she picks up and runs fine again.
Looks to me like fuel starvation...

Cleaned carb, checked filter, changed plugs, still the same.

Serial numbers are 6G1 S 018937



Second question.

There are 2 green wires coming from the motor that are not connected to anything. Are these from a charging coil?

Thanks in advance for any tips.

Re: Mariner 8hp lose power on full throttle

It's been a while since I was here, but to see the news that "You last visited: December 31st, 1969" was a surprise!
I'm sure I've been here since then!!!

Click to expand...

When the forum went to new software some months back, everyones started off saying that. After the first post, it moved on............. as yours did.

Sounds like lack of fuel is your problem. Might try squeezing the fuel bulb when it starts sputtering, and see if it picks up. Fuel pump may be week.

Re: Mariner 8hp lose power on full throttle

Thanks Don, I'll give the bulb a squeeze next time, should get to the boat before the end of the week.

Anyone know about the wiring?

Re: Mariner 8hp lose power on full throttle

Tried and failed!

Pumping bulb made no difference.

Carb has been stripped and cleaned, so has fuel pump.

Could it be an ignition problem? Timing or points? It does start easily and run up to half throttle OK though.......

Re: Mariner 8hp lose power on full throttle

sounds like its running lean when you pull the choke it richings up the mixture. I would do a link and sinc and see if it helps

Re: Mariner 8hp lose power on full throttle

Probably time to pull the carb apart and check for dirt and/or water. The hi speed jet may be plugged up.

Re: Mariner 8hp lose power on full throttle

Don S said:

Probably time to pull the carb apart and check for dirt and/or water. The hi speed jet may be plugged up.

Click to expand...

Carb has been apart already Don.

Re: Mariner 8hp lose power on full throttle

bgbass.1 said:

sounds like its running lean when you pull the choke it richings up the mixture. I would do a link and sinc and see if it helps

Click to expand...

Call me dumb, but what's a link and sinc?