1973 evinrude 85 horse not opening up

greasemonkeyjmj

Petty Officer 1st Class
Joined
Jul 7, 2008
Messages
264
hey folks i have a 1973 evinrude 85 horse that sat for about 2 years i fired it up 2 weeks ago on a muff and it ran good so i took it to water and it had a miss on #2 cylinder i checked plug spark and it looked good, so i thought fuel. i pulled the carb and one of the screws that goes in the front just below and to the right of the throat was almost completely out, so i tightened it up and went ahead and checked inside of carb. it all looked clean, but i went ahead and blew it all out to male sure. i put it back together and it was hitting on all cylinders. i took it back to water and it started missing on a different cylinder, well we messed around with it, and they all started hitting again, but when you first start off it will jump up on plane and wind up good, then it will start surging like it is runnin outta gas, but when you look in carb throats it looks like a full stream of fuel, but we went ahead and changed fuel pump, but it still does it. while running like this you can spray anything combustible into the carbs and it will pick up and go or you can hit the choke button a bit and it will pick up . usually while you are running it at WOT you can hear it trying to hit on all cylinders. this afternoon we pulled the plugs and # 1-3-4 were kinda oily, but #2 was pretty much oil free and kind of a chalky brown shade and texture. we also tried another fuel hose and bubble. any help would be appreciated
 

greasemonkeyjmj

Petty Officer 1st Class
Joined
Jul 7, 2008
Messages
264
Re: 1973 evinrude 85 horse not opening up

i also wanted to mention that the stator has been oozing for about the last 4 or 5 years
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: 1973 evinrude 85 horse not opening up

think you just found one of your problems. the carbs need to be throughly soaked and throughly cleaned, pulling all the jets. reassenbled with new carb kits. a link & sinc needs to be done. you do not mention a compression test, which i would perform before buying any parts. NEVER spray anything other then premixed fuel into the carb. starting fluid burns too hot, and can burn a hole in a piston.
 

greasemonkeyjmj

Petty Officer 1st Class
Joined
Jul 7, 2008
Messages
264
Re: 1973 evinrude 85 horse not opening up

ok compression is 95 lbs on #1 115 lbs on #2 90 lbs on #3 110 lbs on #4 this is without starting engine, just turning it over. made a spark checker and none of the 4 would cross the 7/16 gap so i changed stator and now all 4 coils fires a blue spark hot enough that you can hear it popping. it seems to start alot easier now than before. after it ran a few moments on the muff, it doesnt turn over but a half of round and will start up.,so i am going tomorrow and run it to see what happens. also usually i use wd-40 or something to that effect since it does at least have some lubricating quality to it
 

wavrider

Chief Petty Officer
Joined
Nov 26, 2007
Messages
543
Re: 1973 evinrude 85 horse not opening up

Sounds like you are on the right track.

You might want to look at your primer bulb and fuel lines also, this could cause a poor performance at high speeds.
 

hoeser

Petty Officer 1st Class
Joined
Jun 18, 2006
Messages
253
Re: 1973 evinrude 85 horse not opening up

I wouldn't use WD-40 either, just put some standard gas/oil 50:1 mix in a spray bottle and use that.
 

greasemonkeyjmj

Petty Officer 1st Class
Joined
Jul 7, 2008
Messages
264
Re: 1973 evinrude 85 horse not opening up

ok it still doesnt run. took off and it would run up around 4,200 rpm and was on plane and doing pretty good, then it just started dropping rpm and wouldnt even try to plane out.we kept messing with it,and hitting the choke a bit and it would pick up and try to run better we had another power pack with us so we went ahead and changed it but it didnt help..so now we have tried fuel pump, fuel hose and bubble, power pack,and stator.after we changed stator ot runs a bit better in the fact that before the plugs would stay oily, but earlier today 3 looked real good,but one was still a bit oily, i came home and went ahead and pulled the carbs all the jets looked clean, but i tore them down and have them soaking. all 4 cylinder was throwing a good 7/16 spark so i would figure the fire is good only thing i havent changed is the coils and timer base. what is the symptoms of a bad base ? and with it running better when choking it a bit seems to point to fuel
 

tschamp20

Petty Officer 1st Class
Joined
May 10, 2006
Messages
317
Re: 1973 evinrude 85 horse not opening up

i went thru basically the same symptoms as yours. after replacing timerbase,stator,4 coils and powerpack still had the problem.carbs were also rebuilt. somebody recommended to take off engine cowel(cover) at night while running to see if there were any shorts. VOILA!! big bolt of lightning coming out off the sparkplug boot. as soon as i grabbed it the motor came back to life. replaced boots and used dielectric grease to seal it.its been good ever since. i hope you get lucky with yours. its free to check.
 

greasemonkeyjmj

Petty Officer 1st Class
Joined
Jul 7, 2008
Messages
264
Re: 1973 evinrude 85 horse not opening up

its worth trying, but ill have to wait till i get carbs put back together and back on engine
 

greasemonkeyjmj

Petty Officer 1st Class
Joined
Jul 7, 2008
Messages
264
Re: 1973 evinrude 85 horse not opening up

UPDATE ok while i had my carbs off i decided to check my compression again using a better gauge. all 4 cylinders have 115 to 125 lbs of compression. next i hooked my spark checker onto the plug wire from the cylinder that had the plug that was looking oily. the engine has to spin around 6 to 8 times before it will spark, and if you keep spinning it, the spark gets erratic, it doesnt fire every round, you can watch it skip. i couldnt even get numbers 2 and 4 to throw a spark. and as far as # 1 it would start sparking as soon as you hit the key, but it also was acting erratic.
 
Top