71 Johnson 100 hp V-4 wont start w/o started fluid

vansickle

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Aug 5, 2007
Messages
8
Please Help.

I can't get my engine to fire up without spraying started fluid into the carb.

I haven't ran it for two years, but it done this before. When its was warm, it started fine. However, with first start and when I went fishing and sat for several hours, it wouldn't start very easy. It took a while to start and I kept wearing down the new battery. Now I can't start it without started fluid.

I just learned a few minutes ago that I should be using a spray bottle with mixed gas in it instead of started fluid.

Anyways, I checked the compression and all four cylinders are running about 100 psi. I also have new spark plugs

Can anyone give me any other suggestions about what to do? I'm not very experienced at this stuff. I even called some of our local repair shops and they tell me to buy a new motor. But, I can't afford that. This one seems to run fine once it gets started. I'm just afraid to trust it right now. The last time I used it, I had to row back to the dock... I didn't know it would start with the started fluid. I learned that after I got it home.

Can anyone help me? Thanks.

Jerry
 

dreamchaser

Petty Officer 1st Class
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Aug 31, 2006
Messages
228
Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

Jerry, when was the last time the carbs where rebuilt? sitting for 2 years can plug em up.
 

HighTrim

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Jun 21, 2007
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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

def sounds fuel or carb related...
 

tashasdaddy

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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

1st thing NEVER use starting fluid on a 2 stroke. easiest way to burn a hole in a piston, and strips lubricant of the walls of the engine, as does carb cleaner. use premixed gas in a spray or squeeze bottle.

it's time for a proper carb cleaning, including removing the high speed fixed jet and removing the core plug on top of the carbs to clean the low speed orifices, i use a small dowel to tap the new core plugs back in. you need the special tool # 317002 to remove the fixed jets. or make you own from a quality screwdriver. i made mine with my belt sander. the left picture is courtesy of our good friend FR.
 

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F_R

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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

Van, it might be the choke. Try "helping" it by gently holding it closed with your finger. If it fires right up, check back here for further instructions. Your choke may or may not have been rewired. There was a service bulliten on this.
 

vansickle

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Aug 5, 2007
Messages
8
Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

Thank you everyone.

1) I did check and made sure the choke is closing completely when it is trying to start and it did. I was hoping I just needed to adjust the choke plates.

2) It done this 2 years ago befor it sat. I tore the carbs apart two years ago when this problem started. It sat for two years because I didn't trust taking it out. I think it was after I tore the carbs apart is when I realized it would start w/ starter fluid.

I might not of got everything out and I guess I should rebuild the carbs. I didn't replace everything before, I just cleaned it. Maybe there is a part in there I didn't get cleaned or an area that I missed.

It sounds like it might have been hard to get under the perm jets and I'm sure I wouldn't have cleaned there if I couldn't get it off.

I will order the rebuild kit and try that. I assume there are instructions and I won't need a manual yet. I should prob get one eventually.

Thanks for the info. I might need help figuring out those "high speed fixed jet and removing the core plug on top of the carbs to clean the low speed orifices".

Thanks again.
 

HighTrim

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Jun 21, 2007
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10,486
Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

Someone had a good video link on here on a carb rebuild where he shows the tricks to getting at everything, hopefully someone reading this will be able to re post it, i myself forget the address.
 

vansickle

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Aug 5, 2007
Messages
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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

How much should I expect to pay for a carb rebuild kit?

RE: I just went back to the web site and found the parts section. Nevermine.
 
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F_R

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Jul 7, 2006
Messages
28,226
Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

Van, I don't think you understood my comment about the choke. That motor has a two stage choke. If only one stage is working, it will close the plates. But not tight enough, and engine vacuum will suck them open prematurely. My suggestion is to close them tighter with your finger to see if that helps.

The service bulletin involves rewiring the choke so both stages are energized by the choke switch.
 

vansickle

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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

Ok. I will try that tonight when I get home.

I had the carb cover off last night when I was trying to start it and I saw the front covers stay closed. I even adjusted them a little, because the bottom one was open about a 1/32 or so. Just bearly open.

So, is the secondary stage another set of covers or just after the motor starts the covers open.

I have a switch on my controller that I hold the choke closed until it starts. The toggle switch controls the covers. So, I just need to hold the covers down and make sure it stays down, then have someone turn the engine over to see if it will start?

I will try it tonight.
 

ddennis

Petty Officer 1st Class
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Aug 15, 2006
Messages
351
Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

and DON"T use starter fluid! there is NO lubrication in it...gotta have lube or you will damage that engine!!
 

Buzzy

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Aug 24, 2002
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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

I have a 72 100hp Rude same thing happened to me this weekend. Ran great on saturday the would not start on sunday with a dockfull of kids that wanted to go tubing again I think it is fuel. I have an email into a mobile mechanic to come lookat it this week... hopefully. let you know if i find out anything usefull I will be asking lots of questions @ $50/hour.

Buzzy
 

dreamchaser

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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

50$ an hour .......send him my way, lol .just kiddin
 

vansickle

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Aug 5, 2007
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Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

Lets try this again. For some reason I cant get the Quick Reply to post.

Anyways. I came home today and had my wife turn the engine over as I was holding down the choke plates. As I was holding them down, stuff started to come out of the carb. It looked yellowish, like the gas had varnishized. I also thought I saw a little water mixed in come out.

Anyways, I had me wife keep trying to turn it over, trying to get some more of the stuff out and I decided to prime the ball as she was trying to start and the engine finally fired up.

I think it may have been the primer ball not working correctly. Tomorrow I hope to get a new primer ball and will try to start the engine and let it run for a while.

I didn't have the time to let it run because I had to get my son to football camp.

Wish me well.

Thanks everyone. I've learned a lot by reading some of these threads.


Thanks again. I'll keep you posted.

Jerry
 

tashasdaddy

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51,019
Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

thats the nasties coming out of the carb float bowl. time for a cleaning and rebuild as i stated before. you just flushed all that stuff thru the jets. there's more there. are you using portable tanks, or built in tank? if built in sounds like you need a fuel/water separator.
 

vansickle

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Joined
Aug 5, 2007
Messages
8
Re: 71 Johnson 100 hp V-4 wont start w/o started fluid

I have a built in tank, but I've been using the portable tank since it has been sitting. It probably won't hurt to put one on just in case. My built in tank is exposed to the elements and cound be sweating. I didn't think I had any water in my gas. I had a little in the metal tank and I added another gallon of mixed gas to it.
 
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