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1978ish Mercury 70HP Cold start problems

jn6570

New member
"This motor is very hard to st

"This motor is very hard to start when cold. After it warms up it starts and runs great. Cleaned carbs, New fuel pump kit, Good Fire. Just real pain when it is cold. Push in on key and it tries to hit and after several tries, it finally goes. Any suggestions ?"
 
"Try turning the key on, push

"Try turning the key on, push it in and hold it while counting to 10, then start the motor."
 
"check compression cold and ho

"check compression cold and hot see if there a big difference. also check to see if your reeds are sticking could be sticking untill enough gas and oil gets in then break then free untill sits and dries again (cold start) may have slight deposit around cage causing reeds to stick. One more check how old are the spark plugs, sometimes they look great but are electronicly worn causing high resistence and weak spark and cold normaly makes it worse."
 
"It sounds to me like the chok

"It sounds to me like the choke isn't closing tight enough.

Try this: Take some duct tape and temporarily close off the top hole in the choke plate on each carb. See if that improves starting. I've used this trick on my Merc 500 and it helped.

Jeff

PS: Mine does the same thing, by the way."
 
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