Mark W
Well-known member
Took it up to "a guy" who has been repairing motors for a very long time. Would have liked to have worked with Tom but our schedules were different as I really needed the motor for the season. Once again, many thanks to Wicker T for the help and advide and the offer of a smaller motor for the rest of the season until our 15 hp could get fixed.
So, now we see how good this guy is. by my description of the problem he was certain it was a bad head gasket. Took the boat and motor up near Cambridge and he put a compression guage on it. I couldn't see the numbers (I think it was slightly more than 100) in each cylinder and both cylinders were identical in compression. He thought the plugs looked OK for me just having replaced him. He wanted to see the old plugs which I tossed some time ago.
When he went to take the head off, 2 of the head bolts were not tight. He noticed this right away. Took the head off and there was no scoring on the inside of the cylinder walls and the pistons looked good as well. The head gasket did have a slight amount of blow by. not much but a little bit. He was certain that this is what was causing the problem. Put the new gasket on and the motor fired right up on the 2nd pull. It was way harder to start before the new gasket. He checked the water pump (good) and the thermostat (questionable so I replaced it). Everything looked good and the motor ran fine until we hooked up my gas hose to it. The bulb would not get hard. Also notice a slight leak of fuel on one of the fuel hoses inside the motor. Tightened some clamps and the leak went away.
On the way home I stopped to pick up a new fuel hose. Guy behind the counter said that he thought the hose and bulb were good. He asked if we pumped it horizontally or vertical. I said horizontally. He said sometimes the balls on the check valve don't work that was and told us to go back out, hook up the hose and try pumping it in the vertical position. Sure enough worked as good as new. Wonder if something got stuck in the bilb or am I being fed a real good line of bull.
Drained and filled the lower unit oil. It wasn't foamy and there was no water in it. It was dicolored somewhat and it obviously hadn't been changed in awhile
I intend to take the motor out tomorrow (going to rain here any minute) or so and see how it works. Sure ran better after the new gasket was on. Also will take Tom's advice and run some Power Tune thru it. I've not had a motor such as this one. In front of the carb there is a small plastic plug that can be removed. Removing it does nothign that I can tell. I tried to remove the plastic piece in front of the carb and can't. Does the little plastic plug cover where I insert the Power Tune plastic tube? I've never fogged this engine and can't see an easy way to get the the carb throat> On our older motor is was a simple thing to reove and the carb throat was right there. Not the case this time.
I'll let everyone know how it runs. Would it be obvious if the head was cracked?
Mark W
So, now we see how good this guy is. by my description of the problem he was certain it was a bad head gasket. Took the boat and motor up near Cambridge and he put a compression guage on it. I couldn't see the numbers (I think it was slightly more than 100) in each cylinder and both cylinders were identical in compression. He thought the plugs looked OK for me just having replaced him. He wanted to see the old plugs which I tossed some time ago.
When he went to take the head off, 2 of the head bolts were not tight. He noticed this right away. Took the head off and there was no scoring on the inside of the cylinder walls and the pistons looked good as well. The head gasket did have a slight amount of blow by. not much but a little bit. He was certain that this is what was causing the problem. Put the new gasket on and the motor fired right up on the 2nd pull. It was way harder to start before the new gasket. He checked the water pump (good) and the thermostat (questionable so I replaced it). Everything looked good and the motor ran fine until we hooked up my gas hose to it. The bulb would not get hard. Also notice a slight leak of fuel on one of the fuel hoses inside the motor. Tightened some clamps and the leak went away.
On the way home I stopped to pick up a new fuel hose. Guy behind the counter said that he thought the hose and bulb were good. He asked if we pumped it horizontally or vertical. I said horizontally. He said sometimes the balls on the check valve don't work that was and told us to go back out, hook up the hose and try pumping it in the vertical position. Sure enough worked as good as new. Wonder if something got stuck in the bilb or am I being fed a real good line of bull.
Drained and filled the lower unit oil. It wasn't foamy and there was no water in it. It was dicolored somewhat and it obviously hadn't been changed in awhile
I intend to take the motor out tomorrow (going to rain here any minute) or so and see how it works. Sure ran better after the new gasket was on. Also will take Tom's advice and run some Power Tune thru it. I've not had a motor such as this one. In front of the carb there is a small plastic plug that can be removed. Removing it does nothign that I can tell. I tried to remove the plastic piece in front of the carb and can't. Does the little plastic plug cover where I insert the Power Tune plastic tube? I've never fogged this engine and can't see an easy way to get the the carb throat> On our older motor is was a simple thing to reove and the carb throat was right there. Not the case this time.
I'll let everyone know how it runs. Would it be obvious if the head was cracked?
Mark W
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