will run but not well

[csdwarf]

Alright so i took the boat out today, It idle great and would put around all day

when you wanted to go you would have to hold the choke on (electronic choke)
and if you let off it it would die


it would only go about 3/4 throttle but when we got it home i relized that the last big of the throttle accualy pushes the choke closed so i think thats why it would die out


why can i only run at high speeds with choke on


tommorow im hooking up a racor filter and running carb cleaner through a tank see if that helps

thanks


my outboard is a 70hp johnson

65esl73r

 

[DJ]

Re: will run but not well

First off, you have to tell us what you have.

 

[csdwarf]

Re: will run but not well

its a 70hp johnson 1973

65esl73r


I edited it on the first post

 

[bowman316]

Re: will run but not well

the last big of the throttle?

YOu may have to adjust some settings on your throttle linkage at the motor.

check to see if the carbs are fully horizontal at full throttle.

it also could be a gas supply problem. maybe it is not getting enough gas. the primer bulb should stay kinda hard.

 

[csdwarf]

Re: will run but not well

gas supply is possible but would that make me have to hold the choke to keep it running at high rpm


at low rpm is runs without choke

 

[DJ]

Re: will run but not well

The choke plates SHOULD NOT close as you go to wide open throttle.

I think your cables are misadjusted, not to mention synch./link is way off.

You need a manual. You can probably find one at the library that will get you through the basic adjustments. Otherwise, get the OEM manual.

 

[glassmaster68]

Re: will run but not well

vent on your tank clear or closed?,,a closed vent will cause an airlock,esp when you try to get on it,,also if you have a pump bulb type hose,,it will do that when getting a demand for fuel,,,that happens alot on bulb primer hoses when they get a few yrs old,,,,it will lean out and make your choke kick in

 

[csdwarf]

Re: will run but not well

i might have said somthing wrong


but i have to hold the choke ON to keep it running when going fast

when i put it 2 WOT there is a peice that turns the choke OFF
so it isnt puting the on its turning it off, but it wont run with it off


I cant figure out why it wont run WITHOUT choke at high speeds

(runs fine at low speeds without choke)

 

[DJ]

Re: will run but not well

I cant figure out why it wont run WITHOUT choke at high speeds

(runs fine at low speeds without choke)

OK-Got it.

Most likely a clogged high speed jet. Don't run it like that. You'll melt a piston.

 

[csdwarf]

Re: will run but not well

I already ran it like that some, its seems to be fine tho,no change in compression


i looked at the carbs and there isnt really any way i see to clean them, with the makuni carbs i have experiance with there are jets,

there only one jet i can find on each carb, its on the top and its set,

most of the holes are welsh plugs


how can i rebuild the carb

 

[tootallofwa]

Re: will run but not well

You need a book. The high speed jet is probably behind a plug in the float bowl, where all the sediment falls. Well... it is on my 40hp anyway.

Rebuild your carb.

 

[5150abf]

Re: will run but not well

The jet you are looking for is in the bottom of the float bowl behind the drain plug, you will need a long really skinny screw driver to get it out,.

You need to physically remiove the jet and clean it with a stranded copper wire, peel back wires till it just fits, run the wire through a couple times, reassemble and you should be good.

I have an 81 50, there are 2 jets on top the carb, 1 in front(idle) 1 top back(mid) and the high speed in the bottom, your may be different.

While you are messing wioth it get a fuel filter on it, I am running a universal one iZ got at AutoiZone for $3, haven't had a carb issue in 2 years.

Also change ALL your fuel line from the tank to the carbs, some of it may be 37 years old, it will flake off inside and constantly glog your carb.

 

[bowman316]

Re: will run but not well

i put a clear glass in-line filter on my fuel line, going from the tank to the motor.
It has a filter in the middle of the glass, and the gas goes around the outside.

you just cut the line, and add the filter to it.

 

[csdwarf]

Re: will run but not well

Tooks all 3 carbs off and went through them, they seemed really clean except for the bottom of the floatbowl were that "high speed jet" is, so i cleaned it all up and put the racor filter in, ill go try it later, thanks