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Cold motor wonbt start

J

jdot68

New member
"Hi,
This is my first post an

"Hi,
This is my first post and whatever input I could get would be great. I have a 1990 25hp Johnson outboard motor and the only way I get it started after it's been sitting for awhile is by spraying starting fluid in the carb. Once it has run for awhile I can start it with no problem. I checked the manual primer and it seems to be working ok. Once it's running I get a little back fire through the lower unit, but that may be just an idle speed adjustment. Any ideas would be greatly appreciated.

jdot68"
 
welcome to marineengine!!

D

welcome to marineengine!!

DO NOT use starting fluid.....if you have to prime it use some pre-mix in a spray bottle----50:1.

i am assuming you use the choke even though you dont mention it but does the choke butterfly close all the way?

does it always backfire or only when you use starting fluid?

how does it idle after you get it started?
 
"That engine has a primer syst

"That engine has a primer system.
If Your primer squirts fuel out, does it squirt fuel through the nipple in the carb?
Open throttle fully up.
Activate primer and watch if fuel is getting into the engine. If not, take down the carb and clean the nipple."
 
JDR it sounds like your carby

JDR it sounds like your carby is ok with no problems evident...Morten right your motor does have a primer and if you follow the black hose to where it pushes onto the nipple you can use a piece of fuse wire to clean out the nipple as it sounds like it is blocked.

The other thing is from cold when you prime up the fuel system using the primer bulb. you will notice that the first pull out on the choke doesnt spray fuel in...so i would advise you to try pulling it out and in 3 times and try starting your outboard...lets us know how you go
 
"I hate to say it, but if that

"I hate to say it, but if that is a plastic carb, you have likely ruined it.
If it is plastic, run your finger around inside the venturi where you have been spraying starting fluid.
If is is wrinkled and rough....you will need to get a new carb. It is supposed to be very smooth (no defects). The wrinkles and roughness disrupts the air flow enough to make it run lean."
 
hows the compression?

did y

hows the compression?

did you find out if the choke/primer was working correctly?
 
"The primer has 3 hoses, 1 lar

"The primer has 3 hoses, 1 large hose from the bottom of the carb, 1 small hose to the top of the carb & 1 small hose that runs to the head(I think). When I disconnect the top hose I get fuel flow. I haven't checked yet if the nipple is clogged, I will check that tonight. What is the purpose of the 3rd hose? Also I haven't checked the compression yet."
 
"i think its fuel recirculatio

"i think its fuel recirculation but dont quote me ive never had one that new nor have i worked on the primer system of one that new.....if you look above at my first post i thought it was still the old type.....as you can see if im wrong i will be corrected.......im just glad these guys are cool about it....im an auto mech and still a lil new to the ob world....some things are the same and sometimes its a completely different animal



you can go to http://shop2.evinrude.com/ext/index.aspx?s1=65282fc687943b861e77a2f5df924ea4 and get exploded diagrams and complete parts descriptions...

heres an example.....i dotn know how to post the pics,,,i can barely post pics from my camera

http://shop2.evinrude.com/Scripts/ImgServ.exe/convert?ilFN=E%3A%5CEmpartWeb%5CDa ta%5C41%5C433781%5C11A.TIF&ilSC=16&ilIV=0&ilBR=0&ilIF=P&ilRE=8"
 
"No, I am specifically talking

"No, I am specifically talking about the plastic venturis. If your venturi is metal, you are probably ok regarding carb damage."
 
"GOT IT!!!
I had a blocked pr

"GOT IT!!!
I had a blocked primer nipple at the carb. I cleaned it out and it fired right up! I want to thank everyone for their input, it really helped
JD"
 
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