73 Johnson 50 50ELS73R (added pisser)

[hotshot123]

first off, a little history, this motor and boat was in the way over at my neighbor's when he went to turn his garage into a new addition so he gave me the boat and motor for free. the problem is/was, it has sat in his garage for 30 years. i did the basics that a read here on getting an old motor going and here is where i am at. Under the cover looks brand new. i have unbelievable compression at 175 and 180. i had to do a little work to get spark, it wound up being a problem with the timer base. Even tho i am planing on going through the carbs, i got impatient and hooked the gas line up just to see if i could get anything to happen. pumped the bubble, hit the switch and it fired right up! i let it idle for maybe 10 seconds and shut it off to go get the water hose and muffs. got all that hooked up and water flowing but now it wont hit. I went and pumped the bubble again and noticed that now it wont get tight. i cant hear any leaks or see any leaks. after several pumps i decided to try cranking again. Locked up. pull out top spark plug and it is wet, pull out bottom plug and i get a bath of premix on my lower torso. i go change clothes and with the bottom plug out, everytime i pump the bulb, the gas just flows right out the bottom cylinder. if i spin it over with the gas line connected, it sprays out about 10 feet every stroke of the piston. before calling it a night, i left the line off, spun it to get the gas out of cylinders, put the plugs back in, spun it again and it fired up and shut right down due to no fuel line.

After all that my question is, do you all think rebuilding the carbs should fix this or does it sound like i have a reed valve problem too?? im just not well schooled on how the reed works nor how it would allow fuel to freely flow into the cylinder like that. Hopefully, i willl be attacking the carb kits this weekend and if time allows, water pump too.

 

[jbjennings]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Rebuilding the carbs should take care of it, possibly a hole in the fuel pump diaphragm, but I'd do carbs first. It's likely the float needle is stuck open on the bottom carb.
You'd be doing yourself a disservice not changing the water pump impeller, as it is most assuredly taken a set from sitting.
I'd most definitely change all fuel lines as well.
Good luck,
JBJ

 

[RogersJetboat454]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

IMHO, it sounds like the fuel pump is leaking into the crankcase.

Wouldn't be a bad thing to rebuild BOTH the pump and the carbs. Considering their age, and considering any rubbers inside them will not be ethanol tolerant.

 

[hotshot123]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

thanks guys, yeah everything youve mentioned is or will be done as my spare money allows. Ive already got the water pump but have not got that far yet. i have replaced all the hoses. they were hard as rocks. i am going to get my carb kits today and i guess a fuel pump kit too. I was just hoping to hear what i heard. I have a list of things to do/rebuild and such but i was hoping for not too many expensive suprises. sounds like you guys think its either carbs or fuel pump or both and those items were already on the list and in the budget.

 

[hotshot123]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

on this fuel pump, could someone tell me what the brass fitting is for? im just curious because when i had the lines off, i connected the inlet hose and pumped the bulb. when i pump, fuel squirts from the black center connector but i dont think anything cam out the brass fitting on the right. Just wondering what it does. if i remember correctly, the hose from it is short and goes to the top carb area. almost needs to be a formed hose since it is so short and both fittings point down.

 

[F_R]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

From the left: Fuel in, fuel out to carburetors, pulse hose to crankcase. Pressure/vacuum pulses in the crankcase are what makes it work.

 

[hotshot123]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

rogers, you were right- i am an idiot, i first connected all the hoses to the motor then attached them to the pump. i had the pump side crossed wit the vacume side and i wa puming gas right down the intake...o well, i saw that rigth before pulling the carbs and i fixed the problem but still it wouldnt start. guess what? when i filled that cylinder with gas and tried to start, i sheared the woodruff key. i fixed that yesterday with a new key and it started right up. i am still going to go though the carbs and such but i wanted to hear it sputter.

now i have a water pump question, should i start a new thread?

 

[samo_ott]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Hey, I just got the exact same engine last week. So I'm going to follow your thread

 

[hotshot123]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

samo, there are a couple of other guys here with this mototr too, if i can locate them , i will hook you up on those threads too.

 

[samo_ott]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Thx. I just got it cheap for $100. It has compression but the PO said no spark. I'm concerned about the electric LU but will see what happens. I also got for free a '71 Johnson 50 last fall. The power head looks the same so I'm hoping I can use the power pack off it. But from what I have read the lower units are light years apart!

 

[hotshot123]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

samao, i have the lower unit off mine now and from what i can tell, it is very straight forward. bisically looks like every other omc LU i have ever seen. BTW, i changed my thread title to simplify posting all my issues here and not just carb issues. My next project is water pump, i have it all out now and will be ready to go back together as soon as a couple more seals come in. I am a little concerned that my impeller and all that looked great but it sure seemed to be getting warm quick when i had it on the muffs. I blew air through the water tube and it came back out the leg so i know its no clogged or anything and also it gave me a better understanding of where i should be seeing water come out since there is no pisser on this motor. I am seriosly considering doing the mod this weekend to add the pisser if everything else goes as planned

 

[samo_ott]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

From what I have read it is not supposed to be a normal mechanical shift LU, it's a hydraulically assisted mechanical shift

 

[hotshot123]

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

Re: 1973 50, should rebuilding carbs sove this?? 50ELS73R

it maybe something up near the top around the cable but from the cowl down, it is just a shift rod going into the LU just like the rest of them.

 

[hotshot123]

Re: 73 Johnson 50 50ELS73R

Re: 73 Johnson 50 50ELS73R

i have a new question that i will post here in hopes it still gets seen. On my motor, at the bottom front of the cowling, there is a knob for the low speed jets (i think thats what they are). anyway, yall know how it says lean clockwise and rich is counter right? well when i popped the linkage off, both jets were about 1/4 turn out. my problem is, my little boy may have messed with the knob. 1/4 turn out seems like it would be lean side but i had the knob right in the middle when i started. when i put the linkage back on, with the knob turned to lean, about how far out should the jets be if any??

 

[jbjennings]

Re: 73 Johnson 50 50ELS73R

Re: 73 Johnson 50 50ELS73R

There's no set number, but usually I start with about 1 1/4 turns out from lightly seated. That's with the knob UNATTACHED. Then I slowly turn in it clockwise with the motor running AT THE LAKE, on idle, until it begins to sputter/cough/sneeze. Then I back it off until it smooths out, put the knob back on and go about my business. When you start screwing those idle needles in, you should hear your engine pick up rpm's until it starts lean sneezing. Since you have 2 carbs, you'll have to set them both. I also believe you'll have to take off the air box cover to do it right---can't remember.
There's a good carb setting procedure by a master mechanic--Joe Reeves, in the "top secret files" that should be helpful.
GOod luck,
JBJ

 

[hotshot123]

Re: 73 Johnson 50 50ELS73R

Re: 73 Johnson 50 50ELS73R

Thanks JB, Yeah i got the cover off and the connectors for the linkage, maybe it did run good at one time set at 1/4 turn out but after i rebuilt the carbs, it seems to run good at about 1 turn out. when i put the carbs back on and set them exactly as i found them (1/4 turn open) it would not stay running without choking it from time to time. after i went through the process you said to try, it seems perfect at 1 turn out. I think i will leave the airbox off until i can get it in the water though. I guess once i find the sweet spot, then i can re-attach my linkage for the knob and have the knob set in the center of what runs the best. that will leave me some room to turn the knob either way on the front of the engine if there is a need for it.

 

[hotshot123]

Re: 73 Johnson 50 50ELS73R

Re: 73 Johnson 50 50ELS73R

well i finally added the pisser to my 50 but the camera was dead so i didnt get to take any pics. really wasnt much to take pics of tho. removed the lifting eye, drill hole with greasy drill bit, tap hole with greasy 1/8 npt pipe tap, then i took a peice of wire with grease on the end and fished around in the hole to get any missed cuttings . screwed in 90 degree elbow with 1/8 in barb, ran hose out through a hole i drilled in the lower cowling and hey! i got a working pisser now. Soon as i can get the camera batteries, i will take pics of the finished job.