1971 Mercury 20 Hp (200)

[mrpellaboats]

I have been struggling with this motor for a while now. I replaced the needle valve and seat with a new one. The new one came with a metal washer instead of a rubber or plastic or ring at the seat. When the motor is running there is gasoline gushing out of the float ball overflow hole. It seems like a float issue, the float itself seems to float fine. Any ideas?

 

[SteveVT]

Here's a couple of things to check re new floats and fuel needles:

I had a recent situation on an old Evinrude where the float arm caught on the new plastic washer supplied with the late OEM kit -- the original didn't have a washer (or I found none when taking apart). The diameter of the washer was such that the arm stop caught on it.

Also on the same engine, the new (OEM) . float (cork) was very slightly larger than the old, so it rubbed on the side of the float bowl. So much for OEM quality control!

To test, with the carb out of the motor, invert it and right it several times, listening to the float fall. If it ever sticks, investigate.

Also, if there are any clips for the needle, make sure it is installed right. The Evinrude had a hole in the arm that looked like the clip fit in, but, nope, you were supposed to leave it loose, and not in the hole. Why a hole then? Heaven knows.

Finally, probably obvious but make sure float height is set to original specs. There were all kinds of wrong opinions about that one before I found a good reference.

Oh also, on my Mariner, I had a leaking float seam that emptied itself out by the time I had the the carb bowl off, so it looked good but wasn't. only by prying gently on the seam could I see that it was loose.

Good luck!

 

[mrpellaboats]

I don’t see how the float level is adjustable on this one. I’m considering taking the new needle out and replacing that steel washer with the original plastic puck washer. The float itself is just a bobber type and seems to float well on gas. I don’t sense it to be taking on gas at all.

 

[flyingscott]

Are the 2 levers on the needle? That is your adjustment.

 

[SteveVT]

if you take the new needle out and replace it with the old, you may need to do that with the seat as well. I've seen new needles and seats that had different angles than the ones they replaced. Each will work together, but mixing and matching won't.

 

[mrpellaboats]

There are two levers, but how does one determine how far to adjust (bend) them without reassembly and disassembly several times?

 

[SteveVT]

Do you have a manual? For this kind of thing, I think it's important.

 

[mrpellaboats]

Unfortunately, I do not.