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1974, 40hp Cooling issue

A

ali'i

Member
posting this for my neighbour,and wondering if he just got ripped off. He just bought a boat with a 1974, 40hp Johnson, 15", with electric start. When the motor is started when cold, it takes a good minute or two before any water comes out the pee hole, seller told him its thermostatically controlled, and no water will come out until its warm, which is what happens, is this normal for his motor? Thanks
 
The 1974 40hp Johnson does not have a thermostsat nor does it have a water outlet telltale... what you refer to as a pee hole.

What is the model number of that engine so that we can tell you exactly what your neighbor has? Whether your neighbor got ripped off or not depends on the price he agreed to.
 
by "pee hole" I just meant were water comes out, but is more of a spray out the exhaust port. He did check the model number on this site, which showed it as a 1974, but I will get it when he gets home and check again

joereeves said:
The 1974 40hp Johnson does not have a thermostsat nor does it have a water outlet telltale... what you refer to as a pee hole.

What is the model number of that engine so that we can tell you exactly what your neighbor has? Whether your neighbor got ripped off or not depends on the price he agreed to.
Click to expand...
 
Water should come out with the exhaust in about 3 -1/2 seconds.-----If it does not there is something wrong.....Please note that there were some changes to the 40 HP models after 1970 or so and they are more like the motors of the late 1950.
 

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That is the 74 model !-----No thermostat and water should come out almost imediately with the exhaust on motor startup.--That is the way it should be.----If not then waterpump / cooling system needs attention.
 
??? How many screws in the pump housing of the motor in question ??-----My guess is that someone meant to print 74-76 on the link.----All I do is guess.
 
I can't find that when I go to the parts list for 1974 40hp Johnson, and your link doesn't say what year its for. Either way, will have to check here in BC, as shipping costs to Canada from U.S are a killer, not sure its worth over $100 for parts and shipping etc to repair a 40 year old motor, thats only going to be replaced with something newer. Says he might just sell as is....Thanks all
 
New motors are even more money to repair !!---------If the pump housing is deemed good and not corroded you may get away with just a new impeller.
 
The pump kit original part number is 386602 which has been superseded up to 391741. This is taken from the 2010 price book.
 
It is always a good approach to do a full inspection of a motor before spending a " loony " on parts.--Be a shame to repair a waterpump to find out there are scored pistons / bad piston rings.
 
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