over heating

[medic904]

i have a 78 Johnson 135hp. It just started overheating. I checked the water coming out of the heads and its flowing good. Note, This motor doesn't have the **** hole, the water flows back down the lower unit and comes out just above the intake for the water pump. Need help.

 

[The Marine Doctor]

Re: over heating

Check the compression...Thermostats...Poppet valves...and waterpump.<br /><br />TMD

 

[OBJ]

Re: over heating

Hey T.....<br /><br />78 Johnny 135 and I bet a dollar ya' don't know when the impeller was changed out the last time. It's OK.<br /><br />Good thing to do with a engine that's up there in years is to replace the impeller and and t-stats. Usually, the impeller gets old and loses it's memory and the rubber fins don't know to slide aginst the impeller cup. <br /><br />A good shake down as the Marine Doctor suggested won't hurt a bit. Do compression and spark checks and know what the old shaker is doin'.<br /><br />And by all means.....if your serious about keepin' the old girl...get a service manual. Loads a' stuff in there. Worth the price of admission.