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Flushing engine, 1965 Johnson outboard, 33 hp

R

Richtrigg

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Just bought this old 33 hp Johnson outboard & want to know how to flush the engine after use is salt water. On the left side of lower case just above the propellor blade is a metal stip, 6" long & 1/2 " tall with 6 holes on the right side. This stainless steel stip is just about 3/4 inch above a fin that makes it hard to fit an ear muff type flusher. Is this shiny strip with the holes the flush point?. And must the engine be running while the flush is working? And what year service manuel should I buy for this unit? Must it be a 1965, 33 hp only, or would a 1965 Evenrude be the same? How many years was this 33 hp motor made and would any of the years for the 33 hp be techncally the same?
 
It was first marketed as a 28 HP in 62--Then became 33 HP in 65 and was last marketed in 70.Most parts are interchangeable over the entire production run.--------You could make another temporary plate with a fitting for a hose to bolt in there to flush it.Run the motor while flushing.Best to block of the other screened water intake behind the prop while flushing.Actually a very rugged motor that uses the same crankshaft and connecting rods as a 40 of the same era.
 
Thanks for the info. Do you have any idea where to download an inexpensive service manuel for this 33 hp Johnson. I found I place that had a manuel covering 2 hp to 40 hp for my year for only about $9.00. Would this be helpful in your estimation. I fear a manuel covering hundreds of models my be too general
 
What is the upper screen? I have a parts catalogue for the 65 and it shows a cylindrical screen about 2 or 3 inches long behind a plug. The parts list identifies the screen #302521 and the Plug, Water intake screen #300077. How is this plug removed to clean the screen? I didn't notice a screw slot when I looked at it. This may be a dumb question but if the plug is solid, how does the water get past the plug to filter throught the screen? This screen is located in a part called "Gearcase & Bearing Assembly", just above the propellor. As you can see, I have a lot to learn about boat motors.
 
Simple , the screen is pushed in and then the plug is installed.------------The plug holds the screen in place and that is all it does !!
 
Is the plug pushed in like a cork on a wine bottle, or what holds it in place?. As I said, I saw no. screwdriver slot to unscrew the plug.
 
This is a one time assembly technique.--------------They install the screen and hold it in place with the plug.---------There normally is no need to work on this over the life of the motor !!!!
 
I am puzzled by this screen which never needs removed or cleaned over the life of the motor. It seems to me, and I admit my ignorance of the whole issue, that a screens purpose would be to filter or strain out debrie or impurities of some kind, or why is it there?> . And if it strains out or filters, it seems that it would need to be cleaned at least occationally. But maybe I misunderstand the whole purpose of this screen and its function.
 
In 40 years of repairing these thing I have never seen one of these intake screens plugged.----I suppose in some areas there is lots of garbage in the water and it could be a concern.
 
I'm still learning to use this forum and so don't know how to direct a question to a particular person. Racerone, you have years of experience working on these old motors. I'm mechanically inclined but but don't know squat about boat motors. I still don't understand the cooling system; where the water is sucked in and where it comes out?. I have a parts catalogue for my 65 Johnson and on page 18, a part number 10 is called ,"Cover, water by-pass". This is the retectangular plate with the 5 holes on one side. Is this the water intake for the cooling of the lower engine? Is this what needs water put into it, so that it can come out of the upper screen with the plug covering it?. What does this water circulation cool exactly? Is it strickly the lower gears systems or does it go to the upper engine at all. I am clueless, that is why this forum could be so helpful to a boat motor novice such as I. Thank for any help anyone can offer.
 
Sorry, my factory maintenance manual ( 66 version ) ----Calls the area where the screen is the--------WATER INTAKE----This is the water supply to the pump that cools the powerhead.------------The oil and gears are water cooled simply by the fact that they are submerged --End of the story.
 
kimcrwbr1 said:
These are for my 1969 40hp the one with the hole holds the screen in my guess is it reduces the pressure on the water pump when your running WOT my 61 lark has a solid plug. If the screen has been painted use a wire brush and make it shiny and open tha holes as much as possible.
coilplacement012.jpg
[/QUOTE Kimcrwbri Thanks for the picture of the screen, washer & plug. Nobody has told me how to remove the plug. This picture is very similar to what is called "Plug, water intake screen" in my parts book. Again, please tell me how to remove the plug, or should I just leave it alone and assume it is clean. I am getting mixed signals here. ]
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Thanks for the tips about the thermostat. I didn't even know that it had one. And about the manuel. And about the fact that it has two exhausts an upper and lower. I live in a place that gets very cold at times, so is there a special precaution I should take against freeze damage or does all the water drain out by gravity? That upper strainer cap still concerns me so can it be easily removed to check the screen or is it a factory job to be left to professionals. Thanks again.
 
The screen could be considered " self cleaning " as it sits in turbulent water from the prop !!!-----------------And no -----THERE IS NO THERMOSTAT on the 33 HP model.
 
kimcrwbr1 said:
You just clamp it to the fin and hook up the hose I found this one at auburn marine but I cant find one on the net.
th_hoseadaptor002.jpg
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I am on a search for one of these flush adaptors. You mention Auburn Marine where you bought one. Can you give me a phone number for this dealer. There are dozen by that name in the country. Thanks
 
Thanks. I checked the motor more closely today and noticed that the intake screen and the intake plate with the 5 holes in it are both very close and both draw in water for the impeller. Does the adaptor cover both of these intakes? Also I ran the engine in a 30 gal trash can and noticed the upper exhaust didn't always have water coming out while idleing in neutral. Is this normal?
 
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Are you 100% sure that there are 2 tubes coming from the pump on the 33 HP model !!!!-----------------OMC used the intake screen like that for about 20 years and on well over a million motors . There is no point in questioning their manufacturing expertise.
 
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