120 looper recirculating system

Walker

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1993 Johnson 120 Looper. In the recirculating system there is an inline check valve and downstream of the flow direction is a nipple on the upper bearing carrier. Should this nipple flow fluid easily in both directions? It seems to me it should because it downstream of the flow direction of the inline check valve. Mine doesn't flow when I test it.
 

clanton

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Re: 120 looper recirculating system

Need complete model number with suffex. Two different engine blocks that year and the recirculating systems were different IAW parts manuals.
 

Walker

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Re: 120 looper recirculating system

Model # J120TLETF<br />There is no visable check valve, just a 90 degree nipple on the upper crankcase head towards the front. I pulled the nipple and theres only a visible hole in the crankcase head.
 

clanton

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Re: 120 looper recirculating system

Parts manual shows 2 tees, the lower having a check valve for that model number. Will look at service manual later
 

Walker

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Re: 120 looper recirculating system

Here's the flow diagram for my motor<br />
boat2.jpg
 

clanton

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Re: 120 looper recirculating system

The top nipple should be open. You should be to tell if it has a check valve. These valves and hoses get the same trash as a carburator. The service manual shows almost the same photo as you have.
 

Walker

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Re: 120 looper recirculating system

There is no check valve at the top but it is clogged. I pulled the crankcase head and the problem is in there. The hole goes in the side between the 2 o-ring grooves and ends behind the upper bearing I guess, because I can't find any other hole. Can't flow alcohol thru it and can't draw suction through it either. I tried to clean it every way I know and nothing works. Even ran a torch tip cleaner in as far as it will go. My next option is I need a used crankcase head.
 

Walker

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Re: 120 looper recirculating system

Clanton, just for future reference. <br />That passageway into the bearing assembly (crankcase head) is an open passageway. Mine was stopped up with something. We pushed the bearing out and there is a scalloped opening up to the bearing seat where it constricts to about 1/32" and then scalloped out to the edge of the bearing seat where in allows recirculated fuel/oil to enter the area between the bearing and the top crankshaft seal.
 
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