1953/54 Evinrude Fastwin 15HP - Won't Idle

[beverly]

Engine starts and runs mid (Start) to high idle (WOT) fine but when I slow it down anything at or below shift it coughs and coughs then dies.

Fuel line has been modified to run on a single line with a after market fuel pump (diaphragm) can be found HERE <=CLICK

Cylinder Compression - Both are the same
Engine was Cold
1st Pull 80
2nd Pull 100
3rd Pull 115
4th Pull 115

Carburetor looks very clean
Fuel bulb is always full and the carb. is getting all the fuel it needs.

New coils, condenser, points, wire and spark plug.
Points are set to .020

Water flow out the back and the barrel water gets hot after an hours of running mid to high range.

This motor will run mid to high fine but when it goes anything at or blow shift points it dies. HELP

 

[nwcove]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

carb looks very clean??? is it see through?? seriously tho, id first try adjusting the low speed needle to see if it has any effect, you may get lucky. but the best approach would be to get a carb kit and float ( if the float is still the old cork one). pull the welch plug for the slow speed circuit and clean the whole thing up with spray carb cleaner, compressed air and a good soak in pine-sol. ( yes im to cheap to buy carb soak!!)

 

[HighTrim]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

ditto

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Some more picture added

 

[HighTrim]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Have you tried leaning out the low speed needle, what were you originally set at from seated?

 

[nwcove]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

float is good, looks like it has had a kit. but....was it cleaned properly? i think i see the mikuni fuel pump hanging under the cowl??? how was the conversion done?

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

It was seat to 1 turn counter clock wise

 

[HighTrim]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Looks like you modified the intake manifold. I have not had good results doing that on the Fastwins.

If you cannot remedy the situation, I would try putting the manifold back to normal, plugging the old pressure line and tapping your bypass cover for a pulse.

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Have you tried leaning out the low speed needle, what were you originally set at from seated?

It was seat to 1 turn counter clock wise and went from there for when it started to cough at shift.

float is good, looks like it has had a kit. but....was it cleaned properly? i think i see the mikuni fuel pump hanging under the cowl??? how was the conversion done?

I just redid the cleaning (sonic vibrator varsol) and blew every hole on the carb. and made sure air was going through the hole and blew some more the other way encase things were stuck inside.

The mikuni fuel pump is under the cowl you see and it gets it pumping action from the one cylinder suck and blow action from the piston. Fuel gets down in the pipe and in the pump . (black liquid/gas)
The fuel bulb still won't give anymore fuel so this is still working.

I'm taking a break for a day or two as my arm isn't suited from pull this motor. The 1975 9.9 is easier.

 

[nwcove]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

It was seat to 1 turn counter clock wise

try another half turn ccw?

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Looks like you modified the intake manifold. I have not had good results doing that on the Fastwins.
.

I don't have the manifold your talking about but i'll assume to put a check valve and return line to make pressure in the tank. Before I do that i'll want to gravity feed it first and take it from there.

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

try another half turn ccw?

I'll try that next time i'm playing with the 15

 

[nwcove]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

I don't have the manifold your talking about but i'll assume to put a check valve and return line to make pressure in the tank. Before I do that i'll want to gravity feed it first and take it from there.

you do have the manifold, but the conversion to fuel pump has to be done correctly. no check valves or return line once the conversion is done right, you should have no issue there.

 

[silver_bay]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Hard to tell for sure from the photos, but maybe the low speed needle is grooved from being cranked down too hard?

 

[nwcove]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Hard to tell for sure from the photos, but maybe the low speed needle is grooved from being cranked down too hard?

i agree , cant quite tell from the pics tho. even if the needle is scored a bit, the motor should idle somewhat ok tho....just not as low and smooth as it could. curious to hear back on how the conversion to single line was done.

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Hard to tell for sure from the photos, but maybe the low speed needle is grooved from being cranked down too hard?

i agree , cant quite tell from the pics tho. even if the needle is scored a bit, the motor should idle somewhat ok tho....just not as low and smooth as it could. curious to hear back on how the conversion to single line was done.

Here some more pictures of that small needle

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

Here is some more pictures with a different shades of backgrounds

 

[beverly]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

curious to hear back on how the conversion to single line was done.

Next time i'm playing around with the the 15 I'll snap some pictures and maybe a video of the conversion.

 

[samo_ott]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

The needle does look grooved but I'd still think it would somewhat idle.

 

[nwcove]

Re: 1953/54 Evinrude Fastwin 15HP - Won't Idle

the ls needle does seem to show signs of being over tightened, but the motor should still idle, but not as well as it should. ( have seen worse tho, and the carb would work "ok"). plz do show how the conversion was done.