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Just bought this 70s 25 Johnson -- Any help is appreciated!

With the carburetor face (throat) exposed, observe it while pumping the fuel primer bulb up hard. If the carburetor is flooding, fuel will be flowing out the front of the carburetor at some point.

It is also possible for the engine to flood via a cracked fuel pump diaphragm.... check as follows.

(Fuel Pump Diaphragm Test)
(Two Hose Type Only)
(J. Reeves)

Note: This pertains only to the regular Two Hose type fuel pumps.

Leave the hoses attached to the fuel pump. Remove only the two screws that attach the fuel pump to the powerhead. Re-insert those two screws and install a nut to each of them so that the fuel pump is securely clamped together. With the fuel line attached to the engine, pump the primer bulb while observing the pressure/vacuum operating hole on the back side of the fuel pump. Should any fuel leak out that hole, the diaphragm is faulty.

If the diaphragm is faulty, the fuel pump will require rebuilding or replacing. Note that repair kits are not available for all fuel pumps, in which case replacing the pump would be necessary.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:
http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
Great. Thanks for the directions. I'll get on both of those things.

Does anyone recommend a particular kind of compression tester? Is there anything I can get from a local auto parts store that would also work for outboard testing too? I'll let you know how it goes in the next couple days.

Thanks!
 
Any compression tester ($8.95, whatever) will be fine, just as long as it will register from 0 to say 150 psi or so.

I prefer the rubber tip models... makes it quick and easy. The scew in models can be a pain at times.
 
Yikes kimcrwbr1.....that link at ebay....$25.49 for that little tester??? Seems I paid like $6.00 for mine....

Ebay can be like that at times; eh?
 
And they can get cheaper yet! :)

(Spark Tester - Home Made)
(J. Reeves)

You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.


Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:




..........X1..........X2


.................X..(grd)


..........X3..........X4

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
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