1985 Johnson 120 Water Route

[zebo007]

Hello all,

I need to find out the water line route on this motor. I just purchased new thermostats and the motor is running cold. I was looking at it yesterday and from what I've been reading the little valve on the throttle linkage puts pressure on the back of the tstats to hold them closed. This valve is not hooked up. I have a manual but a buddy of mine borrowed it and is offshore right now. Does anyone know the route the water line is supposed to take?


Thanks for any info.

Jason

 

[zebo007]

Re: 1985 Johnson 120 Water Route

I found this on another site.

operation water control valve
below 2000 rpm
goes from exhaust adapter housing to t-stat diaphragms. <pushing t-stat into seal in head, aiding in reaching operating temp faster>

above 2000RPM
goes from t-stat diaphragm to overboard drain.
<water circulation pushes t-stat away from seal in head>



So I come from the exhaust adapter housing into the bottom of the water control valve. Then from the left side of the water control valve to the T-stat diaphragms and then the right side of the water control valve out of the cover. Right ? Also I have my water pressure gauge hooked up to the exhaust adapter plate. Should I just put a tee on it or is there another place to hook up the water pressure gauge?

 

[ezeke]

Re: 1985 Johnson 120 Water Route

I placed my water pressure kit tee according to the OMC kit instructions. I routed the line to the top of the engine to prevent air from reentering the water circuit, however.

Click the thumbnails to enlarge, please.

 

[ezeke]

Re: 1985 Johnson 120 Water Route

Did you replace just the vernatherms or the whole plastic capsule?

If you bypass the valve, you should update the thermostat housing, gasket and spring to the 1993 setup.

 

[zebo007]

Re: 1985 Johnson 120 Water Route

All I have is the diaphrams and the all in one t-stats that screw into the diaphrams so I have to hook up the water control valve.

 

[ezeke]

Re: 1985 Johnson 120 Water Route

OK. Facing the water control valve, there are three hose fittings:

Left one goes to the thermostat cover;

Right one goes to the overboard drain (tell-tale outlet);

Bottom one goes to the exhaust adapter housing.

 

[zebo007]

Re: 1985 Johnson 120 Water Route

Ok , I'll try that tonight and see if I can get this motor to heat up. Would this make the motor rough at idle and hard to get on a plane? Carbs were just rebuilt and sometimes it will jump out the water and sometimes it's real slow.


Thanks

Jason

 

[ezeke]

Re: 1985 Johnson 120 Water Route

No, the motor will run OK cold but will foul plugs and eventually damage the cylinders as well as build up a lot of carbon.

I would check the carburetors again, especially checking for any air leaks. Also be sure the engine is firing on all cylinders. You need to do a proper spark test with all plugs out and a tester that will show a 7/16 spark. The Loopers' powerpacks are real sensitive, so be sure to have the power off whenever you are working around the ignition system.

Also, check the pulse limiter on your VRO. If you still have the black one, you should replace it with the blue and gold.

If you get more smoke than normal when you start up, do a decarb using Captain Dunkelberger's Method in the Engine FAQ forum and then clean or replace your recirculation check valves.

BTW, Is all of your fuel fresh?

 

[zebo007]

Re: 1985 Johnson 120 Water Route

Yes, the fuel is fresh. I took the VRO off my 1992 70 to put on this motor and the oil is blocked off. Do you think this is enough pump for this motor. I ran a decarb with seafoam when I first got it about 2 months ago. The motor runs good on the top end. where are the recirculation check valves?

 

[ezeke]

Re: 1985 Johnson 120 Water Route

Look for 4 small hoses leading from the rear of the engine near the pistons to the front, behind the intake manifold. There you will find the 4 recirculation check valves. When functional, they allow flow in only one direction.If they are fouled, they may allow flow in two directions, or not at all. They help to get the excess oil back in the fuel supply so that it can be burned off smoothly, rather than leaving it to pool and burn with a lot of smoke.