1977 35hp johnson

jsb91010

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Re: 1977 35hp johnson

by the way...i did try squirting some juice in the carb with no luck. Still didn't sound any more likely to start. I am printing your last post and am going to try and run those tests...I will get back with my results:cool:
 

jsb91010

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Re: 1977 35hp johnson

ohhhhhh man hightrim...you don't know what you got yourself into trying to teach me this stuff LOL...I am getting a reading of 12.8 for my battery reading...anything other than that I can't figure out how to test. I am holding it where I think it should go and get 0 readings but it doesn't look like the meter is even reading anything, like nothing happend. If i hold the neg probe on the black ground nut from the battery, and hold the red on the selenoid on what I guess to be the "incoming" side i get the same 12.8ish reading. If i took some pics of my setup on that side would it make it easier? Electronics:mad:

EDIT: i just realized that by "give her juice" you mean try and actually start it? I just had the key in on position...I have to wait for my dad to help me so he can start while I read the #'s...Ill get back to you...let me know if im doing it wrong.
 

HighTrim

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Re: 1977 35hp johnson

Sorry yes I meant crank her over, my bad.
 

jsb91010

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Re: 1977 35hp johnson

Sorry for the delay, it being Christmas and all! The wife seems to think that family is more important than iboats, geesh! lol

Anyways, put your black probe on an engine ground, the bolt or cable grounding the starter motor to the engine is a good point, and your red lead on the large input for the starter motor. Note the reading. =12.80 Also let us know the reading of your battery when sitting. Should be around 12.65 volts. = 12.80

Voltage Drop Test

First set your DVM to the 20 Volt scale

Put your POS voltmeter lead on the battery POS terminal and the voltmeter NEG lead on the large incoming solenoid/battery terminal post and give her juice. If the meter reads more than .3 volts, the battery cable is bad, corroded or you have a faulty connection (loose). = .3-.8...i then changed battery cables and got .3-.6

Next, connect the POS lead to the incoming large solenoid post and the NEG lead to the outgoing large solenoid post while giving her juice. If the voltmeter reads greater than .2 volts, the solenoid is bad, corroded or has a faulty connection. Had problems getting this check? don't think i was doing it right...but I do know my selonoid is brand new i just bought it.

Next, connect the POS lead to the outgoing large solenoid post and the negative voltmeter lead to the starter positive post and give her juice. A reading of over .2 volts indicates faulty wiring between the solenoid and the starter.= .02-.04

Finally, connect the NEG lead to the NEG battery post and the POS lead to the engine block and crank the engine. A reading greater than .3 volts indicates a faulty negative cable, corrosion or a faulty connection.=.32..then after with the new wires i got .1

Hope you can tell what #'s i got...Im unsure where to go now...I did check the cylinder with the pencil trick and the top cylinder lines up with the #8 just like I heard it should. The bottom cylinder doesn't appear to line up with anything??? Is this right?
 

jsb91010

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Re: 1977 35hp johnson

ok guys...shoot me now LOL...i just heard it fire over for the first time yet! I was spraying a TON of premixed fuel into the carb..I am pretty sure that leaves me troubleshooting the fuel system now...How can i tell if the fuel pump is working? Do i need to rebuild my carb? I just rebuilt it a couple months ago. Since it just worked fine one day then wouldn't the next, fuel pump?
 

jsb91010

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Re: 1977 35hp johnson

ok...i tried spraying the carb with the fuel mix, and it WILL start...it WILL NOT stay running if i pump the primer bulb, but it WILL stay running if i stand there and keep spraying fuel into carb...sounds to me like a carb problem...I've included a couple pics of my carb. I do have the float set at the right height, right? it's flat when upside down...Any other ideas?
DSCN0169.jpg

DSCN0168.jpg
 

HighTrim

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Re: 1977 35hp johnson

Your float should be set so that the free end of the float, not the side with the hinge pin, is just slightly higher than the other end, pretty much parallel.

Looking at it from the end of the float, ensure that it is not cockeyed at all.

While it is apart, be sure that ALL passages and orifices are completely clean. May want to soak it overnight, then blast with compressed air in the morning. Be sure to remove all rubber and plastic components.

Hold the carb upside down and attempt to blow into the fuel intake fitting. If you can blow into the carb, the needle valve is not seating.

Have a read here as well, good luck!

http://forums.iboats.com/showthread.php?t=244013
 

jsb91010

Petty Officer 3rd Class
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Messages
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Re: 1977 35hp johnson

Your float should be set so that the free end of the float, not the side with the hinge pin, is just slightly higher than the other end, pretty much parallel. That is quite drastically higher.
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so your saying it's not in the right position, im kind of confused what you mean? I thought you held it upside down and made the float level like in the second pic...Let me know how to adjust it right please. Thank you.
 

G DANE

Commander
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Nov 24, 2001
Messages
2,476
Re: 1977 35hp johnson

Float hight is not your problem. Was the carb bowl full, when you took it apart ? Either something is blocket, so fuel wil not get to the iddle jets, the VERY small bors just above throttel butterfly, or is is sucking air in somewhere instead of fuel on the way thru carb.
 

Kenny1970

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Sep 21, 2007
Messages
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Re: 1977 35hp johnson

have you taken it compleatly apart and and soaked it in a gal. of carb dip.or have you used a can of carb cleaner and sprayed in all the little holes with the straw in the holes and made sure it blaster through all of them.Also it has been cold one day and hot the other day alot here in San Antonio.Look for water in your fuel tank. I have learned the water in a carb is thicker than fuel and will not alow the fuel to flow very well.
On My Yamaha 25 hp it has a fuel filter/water filter that I have to dump about every 10 hours of use in a month because it has about 1/4 ounce of water in it.
 

jsb91010

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Re: 1977 35hp johnson

my fuel looks like i think it should...nice and green...will water in there just look like oil and water mix? Should see the water not mixing with the gas? I am pretty sure I know the answer...but...I need to pop out those silver disc looking things on the carb? Every hole is clean on that thing, but I am going to soak it today like yall say...I DID NOT remove any of those round silver disc things though...I am pretty sure I still have them from my last carb kit because I never did either last time i rebuilt the carb...:redface:
 

HighTrim

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Re: 1977 35hp johnson

I DID NOT remove any of those round silver disc things though...I am pretty sure I still have them from my last carb kit because I never did either last time i rebuilt the carb...:redface:

That is likely your problem, follow the thread by Tashasdaddy that I posted on cleaning the carb, the orifices/jets are the most important area for cleaning, and should be done thoroughally!
 

jsb91010

Petty Officer 3rd Class
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Re: 1977 35hp johnson

the orifices are behind those little silver disc's??? Is that what i need the "special tool" for? Where can I get the special tool at? Also...do i just punch in those little discs to bend them with a screwdriver or what? Thanks for you guys help...maybe after this i will really know how to rebuild a carb right!!!:D
 

HighTrim

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Re: 1977 35hp johnson

To remove the "discs", I use a center punch or pick of sorts, tap LIGHTLY into it, then pry/pop it off. To reinstall, you can use a hammer, and the extension for a socket, to tap it back in until it spreads.

The 'special tool' can be made from a standard (flat) screwdriver on a belt sander. Main thing is that it is parallel. Pics compliments of Ezeke and FR.

FixedJetScrewdriver2.jpg

FixedJetScrewdriver.jpg

Be careful not to damage the jet when removing. Alot of guys will simply run wire through them (extension cord, pull back the insulation, then pull away a few strands of the wire), soak them, then blow out with compressed air, but removing them cleans them the best.
 

jsb91010

Petty Officer 3rd Class
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May 4, 2008
Messages
87
Re: 1977 35hp johnson

well..thanks guys for your help...I ended up just soaking it in some solution that was recomended on this site...i installed the carb and waalaaa she ran great...i think even better then before. Ill be at the lake tommorow to really test her :D ...thanks guys for all your help in getting this thing running!!!
 
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