Logo
FULL SITE MENU

Old 4 cyl Merc 650 Coolant Hose Direction

J

Joe Baublis

Member
I was replacing coolant hoses on my Merc 650 circa 1970 but I got confused. Now I can't remember the hose sequence. The hoses are on the starboard side of the engine. 1 hose is about 5/16 " ID, a big one. That's a no-brainer because there's only 2 adapter fittings that fit. But I have 4 fittings that are smaller, about 3/16" for 2 hoses. One fitting consists of a smaller fitting (3/16) that is attached to a big fitting (5/16) fitting, so there's 2 hoses coming of that one - a larger 5/16 hose and a small 3/16 hose. But I've still got 3 open 3/16 hose fittings, one at the top near the flywheel, 1 in the middle by the fuel pump, and one down low. Does anyone know which hose goes where? Photo below shows how it is currently connected, but that may be wrong.IMG_1519.jpg
 
Better not be water... as all them hoses are for fuel and fuel recirculation..
 

Attachments

  • 650.jpg
    650.jpg
    74.8 KB · Views: 32
Last edited:
I try to make these folks think about what they are doing / working on.---------Hopefully they are quick to learn from mistaken assumptions !
 
faztbullet said:
Better not be water... as all them hoses are for fuel and fuel recirculation..
Click to expand...

Thank you Mr. Fazbullet, I have confirmed - you are correct. Those lines are connected to ports that lead into the combustion chamber. I am switching to fuel line grade hoses.

Sir - do the coolant hoses appear to be installed in the correct ports? The upper-most port is connected to the lowest port. Right?
 
racerone said:
I try to make these folks think about what they are doing / working on.---------Hopefully they are quick to learn from mistaken assumptions !
Click to expand...

Thank you Mr. Racerone. You are correct and thank you. I pulled off the carburetors and discovered that the large hose fittings are threaded into ports that are connected to the combustion chambers. So, that clear hose is history - it will be replaced with fuel line.

Thank you.

Do the coolant hoses appear correct?
 
???--------I do not believe there are any coolant hoses on this motor.-----I do not believe there are any hoses in your picture that go directly to the combustion chambers----That is why I suggest you review the assumptions that you are making !!
 
Back
Top