6hp Johnson not running right when warm

[tous0024]

Hello everyone. Hope someone can offer some advice.

I have a 1956 Johnson 6 hp motor that I just purchased last spring. For about the first month of summer the motor ran great. Now the motor runs fine until it gets up to normal operating temperature and then it seems to only run at about 50-70% of its normal power. I have replaced plugs, ran seafoam, and checked all of the hoses. It almost seems like it is getting too hot. I took the lower unit off and checked the impeller which looks fine, but it is my understanding it is hard to tell if it is fine by looking at it.

Water is cycling through, but the water coming out is not a stream, but more of a spray. Could the impeller be bad and that is why it seems to run bad when it gets hot? Any advice would be greatly appreciated.

 

[tous0024]

Re: 6hp Johnson not running right when warm

I was just told this motor is more like 1965.

 

[ezeke]

Re: 6hp Johnson not running right when warm

If it is a 1965, It is a good possibility that the thermostat is bad. I would pull it and test it.

What is the model number on the plate on the transom bracket?

 

[tous0024]

Re: 6hp Johnson not running right when warm

I checked the thermostat. I put it in hot water and it opened right up. The model is CD22M

I crossed the number and it is a 1965 Johnson 6hp.

 

[ezeke]

Re: 6hp Johnson not running right when warm

The new BRP impeller works better than the old ones. I had to change the whole pump but I have not had a problem since. I have the same 1965 motor that you have.

 

[tous0024]

Re: 6hp Johnson not running right when warm

Excuse my ignorance here, but does BRP stand for a brand, model or simply replacement part?

 

[tashasdaddy]

Re: 6hp Johnson not running right when warm

bombadier recreational products. they make seedoo, snow mobiles, 4 wheelers, boats, and outboards, just to name a few.

 

[highwayman]

Re: 6hp Johnson not running right when warm

I have a 75Johnson thats doing the same sort of thing.it runs allright for a little bit and then it will get to where it wont go more than five miles an hour,

 

[ezeke]

Re: 6hp Johnson not running right when warm

OMC or Outboard Marine Corporation built the Evinrude and Johnson 1965 6HP motors, one of which you own. Bombardier Recreational Product is the successor corporation following the bankruptcy of OMC.

The replacement water pump kit is part # 0391391 and is available through your local dealer.

You can find the nearest dealers by following the dealer locater link and selecting the third circle, then entering your zip code:

http://dealerlocator.evinrude.com/EN/?Rnd=1175514465375

 

[F_R]

Re: 6hp Johnson not running right when warm

Get your attention off the cooling system. You'll find the real problem by removing the flywheel. Most likely, the coils are shot.

 

[wbeaton]

Re: 6hp Johnson not running right when warm

Second to FR. That's a classic symptom of bad coils.

 

[tous0024]

Re: 6hp Johnson not running right when warm

Thanks everyone I will check into changing the points. How hard is it to get back behind the flywheel and are the replacement parts tough to find/match on those older motors?

If anyone else has other suggestions have at it.

Thanks again for the advice.

 

[tous0024]

Re: 6hp Johnson not running right when warm

I meant changing the coils.

 

[F_R]

Re: 6hp Johnson not running right when warm

You need a 3-bolt puller to remove the flywheel. A vibration damper puller from an auto parts store will do. Be sure to get some hardened grade-8 bolts to go with it.

Once you are in there it is easy. Adjust the coils in or out till the ends of the laminated poles are flush with the machined posts on the aluminum plate that holds them. Make sure the wires are routed correctly and will not rub on anything, including the flywheel. You'll see what I mean when you get there.

Use a torque wrench to reinstall the flywheel nut to 40-45 ft/lbs. Flywheel and shaft tapers must be clean and dry.

They have coils right here at i-boats. That's the easy part. They also have service manuals. Wouldn't be a bad investment if you are going to be doing your own work.

 

[panther wrestling HWT]

Re: 6hp Johnson not running right when warm

ok i have the same motor but there is no water coming out i am not sure what is wrong i am thinking it is the water pump but i dont know. also how much would it cost to replace the pump assembley