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1973 4hp evinrude

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Bill4734

New member
My 4hp is very hard to start, changed plugs set the gap at 0.030. Put a new fuel pump on it, the old one was leaking. I can start it with a cordless drill and it will start with the pull rope after that, but if it's cold, it won't start with the pull rope. Any suggestions are appreciated.
 
Do you know the history of the motor? How old are the points and when was the carb rebuilt last. It should be a one pull start motor cold. A new head gasket will not hurt either. It is best to use OEM points and condensers and be sure and clean them good with acetone or laquer thinner after setting the gap exactly .020 on both points.
 
That engine is a very good design and should start and run on at least the third pull. The most common problem of a hard starting engine is either a fouled carburetor or a misadjusted one... try the adjustment procedure first, then if no improvement, clean the carburetor thoroughly and rebuild it as necessary.

The above is assuming that the engine has compression and proper spark.

(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
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(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

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