10 hp johnson hard to start

[eddyf]

Need Help Please: <br /><br /> I am trying to get a 1962 10 hp johnson to run without much luck. It is hard to get it to start and then when it does, it does not want to idle or run smooth. I have replaced the coils, points, and condensors, fixed the slack in the armature plate, cleaned the carbs and tried to set the high and low speed jets. Also set the points to .020". I have also tried to set the carb with the mark on the armature plate. The only way to get this motor to run somtimes is to put it gear and open the throttle. The only time I have noticed this motor seem to run right is when I unhook the fuel line and let it run out of gas. Then for a few seconds before it dies it stops sputtering and seems to run smooth. Adjusting the high and low jets does not seem to make much difference. I am not sure what to try next or how to check if maybe I need a carb kit or something. <br /><br />Thanks for any help <br />Eddyf

 

[Paul Moir]

Re: 10 hp johnson hard to start

A carb kit sounds like the obvious solution. When you pump the primer bulb, does the carb overflow with gasoline? What do the spark plugs look like? are they both the same colour at the firing end?<br /><br />The fact that the high and low speed adjustments aren't doing anything points to a fuel delivery problem. By the sounds of it you're getting too much fuel. Sort of like trying to run with the choke on.<br />When you rebuilt the carb, was there a gasket between the main jet and the bowl? I don't know if there is on that model. Did it get replaced?

 

[eddyf]

Re: 10 hp johnson hard to start

The spark plugs look the same colour but there does not seem to be any gas that comes out of the carb when squeezing the bulb. It still has the old cork float-could this be causing the problem. And paul I was wondering where I could get some of that sea-foam up here in the maritimes. I can't seem to find any, or do you use some other product to de-carb.

 

[eddyf]

Re: 10 hp johnson hard to start

I didn't rebuild the carb just cleaned it. But when I did that, there was a little round gasket that was in bad shape so i tried to make a new one out of cork gasket material. It was in the bowl of the carb on the main jet I believe. Should of put a new one on I guess?

 

[Paul Moir]

Re: 10 hp johnson hard to start

I'm afraid you can't get Seafoam anywhere in Canada. Mabey Iboats can send you some in the mail - I don't know. Otherwise, all the outboard dealers carry some sort of decarbonizing agent. Canadian Tire carries something the same colour as seafoam, but apparently it's not the same thing.<br /><br />If it's not overflowing when you pump it, I don't think the cork float could be sunk or the needle and seat leaking. If you're confident your made up gasket is not leaking badly, it's probably OK. I really wanted to make sure it was there. <br />Will the engine run with both mixture controls turned in till they're (lightly) seated? <br />Did you set the float level even with the rim of the carburetor's body when turned upside-down?

 

[Xcusme]

Re: 10 hp johnson hard to start

I think Paul nailed this one. If the gasket you made is not sealing the high speed jet from the carb fuel bowl, she'll suck too much fuel at idle. The gasket is called the Boss gasket btw.

 

[eddyf]

Re: 10 hp johnson hard to start

Thanks for the tips. I have already set the float level. I will try to see if the motor runs with the two mixture controls seated and I'll also put a new gasket on because I'm not to sure that it was thick enough to make a good seal. I'll let you know how it works.<br /><br />Thanks

 

[Paul Moir]

Re: 10 hp johnson hard to start

Seafoam may be available to us. Have a look at BF's post about it in General Outboard Discussion. Go to www.autovalue.com to find a nearby location.<br />Good luck!

 

[eddyf]

Re: 10 hp johnson hard to start

Looks like Paul was right. I replaced the boss gasket with a thicker one that I made and the motor now starts and runs excellent. Thanks for the tips, I was about to give up on this one. It just goes to show you these guys know what there talking about. My next project is a 1982 35 hp with bad compression on one side. I will no doubt be back again.<br /><br />Thanks Eddyfur

 

[Paul Moir]

Re: 10 hp johnson hard to start

I'm glad to hear it worked out for you. And thank you for reporting back.<br /><br />You've got to love the $0.99 fix!