1995 40Hp Johnson Water Pump Install

[plasticman]

Ok, just got my power head back from complete rebuild, looked like I dropped a needle bearing from connecting rod which made the piston look like a porcupine, installed the power head, then dropped the gearcase, opened up water pump AHHA, reason for powerhead failure, only one impeller left and the others floating in the housing, replaced the entire pump. Now, question, when I assemled the water pump housing back on I turned the input shaft clockwise looking down at the top of the gearcase to have the impeller vanes in the correct direction, is this right, please tell me it is. I also did top input shaft seal and am doing the bottom tonight, have bearing unit out but need to have the seals pressed in. Also, when we start this baby up for the first time what should I look for for water flow, should it come out of the rubber bushing at the back side of the engine, is there a thermostat, how much flow should I see. Thanks guys!

 

[Silvertip]

Re: 1995 40Hp Johnson Water Pump Install

You should see water exiting the tell tale hose on the starboard side of the engine cowl. The two exhaust relief ports at the back of the engine will not likely spit anything until you have the engine in the water. You turned the shaft correctly. Did you rebuild the carbs after the engine rebuild. Losing a needle bearing sounds more like a lubrication failure than an overheat failure. Lubrication failures are very often due to a gummed up carb that makes the engine run lean. Running lean means less fuel. Less fuel means less lubrication. Less lubrication means rotating parts failure. If carbs have not been rebuilt, you are strongly advised to do it.. At this point it is cheap insurance against another power head failure for the same reason as the first one.

 

[plasticman]

Re: 1995 40Hp Johnson Water Pump Install

Thanks for the advice, yes carbs were rebuilt to factory specifications, the powerhead rebuilder was once a factory authorized rebuilder, I also asked him to bypass the oil injection so I can run premix, so he blocked it off so as the fuel pump was still active and made the necessary wiring changes to bypass the alarms for the oil injection. So I replaced the new water pump, top and bottom gearcase oil seals so we are pretty much like new, top to bottom. I am in the process of trying to figure out the way the wires were routed from the power trim and such, should have taken a bunch of digital pictures as this is prooving very challenging. Had the marina remove the engine for me in the fall so wasn't exactly sure how the boat harness passed through the cowling and such and how many plugs other than the large red round plug there were. The harness from the power trim wire routing to the engine harness is a confusion right now. does anyone know if this harness passes through the cowling next to the fuel and oil house hookup, is there a grommet for the pass through. I am thinking that there is and this also allows for the other plugs to pass through as well. I cannot find any other way it could pass through. Again thanks. And with respect to the engine leaning out due to gummed carb, I wish I would have thought of this for my snowmobile as it leaned out this winter probably due to this and burnt a hole through one piston. Oh well, I will learn.