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Outboard just cranks wont start

E

Eldorado

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I have an outboard (old johnson) that makes a pop noise sometimes along with white smoke but never turns over. Seems to be getting good spark and fuel. Spark plugs looked dark and wet. Replaced coil plugs and wires. And set points and cleaned carburetors. I feel this may be a timing issue. Does anyone recommend loading it up with seafoam?
 
Haha, 60esl71c I believe. The reason I say it may be the timing is because I adjusted the points and I'm not sure if I did it right. I gap one then I rotated the cam shaft 180 degrees and gapped the other.
 
Eldorado said:
Already did, 130 125 90. I know 90 is a bit low but do able.
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Your cylinder's compression is 30% off from one to the other. If this is correct you have serious issues with the motor. In general you can get away with a 10% variance.


CMOS
 
Pull the head and inspect the cylinder walls it may just need a head gasket? Did you do the compressiopn test with a fully charged battery and test it three times 1-3 1-3 1-3 that accounts for any mistests.
 
The rotor is keyed to the crankshaft.--------Was that carefully put in place ?----Points set at 0.010 ?-------Cleaned the distributor cap and rotor ?----Does spark jump a gap of 7/16" , yes or no ?
 
(Point Setting Of Battery Capacitance Discharge)
( Ignition Models - 1968 thru 1972)
(Some have points - Some do not)
(Joe Reeves)


The points must be set to .010 but no wider than .010..... BUT in some instances due to a possible slight inaccurately machined crankshaft lobe or a slight offset of one set of points, a setting slightly less than .010 would be required as follows.


Whether the crankshaft has two or three lobes, when setting the points, check the setting of the points on each individual lobe by rotating the crankshaft by hand.


You may find that setting one set of points to .010 on one lobe, then turning the crankshaft to the next lobe, the gap measures .011 or .012 (too wide). This is where you would need to close that gap down to the required .010. A gap too wide can result in a ignition miss when throttle is applied.


Bottom line, pertaining to the point setting at the various lobe locations____ .010, .010, .009, is okay____ .010, .010, .011 is not!

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
********************
 
I did the compression tests together multiple times so even if the battery wasn't charged you would expect the values to be similar. I may have to reset points again. Cylinder looks a little rough but so does one of the others( can't remember which). Dodnt Dan cap or rotor. Spark jumps gap and blue.
 
To answer your question. The exact gap is actually more like 1/4 of an air gap. I dont have an actual tester so I just eyeballed it with a tape measure later on. Again, it is blueish white in color. I also just reset the points to approximately .01 as suggested. Will try to start again. hopefully tomorrow. It has been suggested by someone to start it at a quarter throttle. What do you all think? What it be okay to have it in gear on muffs? Didnt try starting it today at all. I feel it may be a seal because adding oil to the cylinder raised the psi by about 5.
 
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CMOS - The point gap is quite critical on those models, hence my instructions above that came of a trial and err scenario. You won't find that procedure in any manual... just something one works out over time.

Eldorado - Unfortunately you have a compression difference of 40 psi between the highest and lowest reading cylinder and that normally spells major trouble, however, I do wish you luck that it's due to something small.
 
Yes that is all I did. It went a long way just by adjusting the points. Another thing, a lot of people say to adjust idle screws 1 1/2 turns from gently seated, but it was only turned 3/4 for now like it says on the original air silencer sticker. Not sure if I need to adjust it or not but seems to idle pretty well. It was actually backfiring because the timing was so off. I know a lot of people will call shenanigans, but that is all I changed since then. I think the gap was too large on the points (.02 or so), as the gap should be around .01 as Joe Reeves has stated. Thank you Joe Reeves for the well wishes. I know I should start a new forum-- but quickly. What should my next step be? I squirted some oil into it at one point and the compression increased a little.
 
Are you running L77JC4 or QL77JC4 spark plugs? You should be. Those plugs make a huge difference in the way those motors run.
 
Some sort of champion plug I believe I got the same one the previous owner used. What gap? I just did around .035 like the previous plugs were.
 
Just checked compression again. 130 120 120. Dont know if there was some sort of blockage that got removed after running or something. I remember running it and hearong it sort of level out so maybe it cleared itself out. So compression seems good now.
 
Eldorado said:
a lot of people say to adjust idle screws 1 1/2 turns from gently seated, but it was only turned 3/4 for now like it says on the original air silencer sticker.
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Eldorado.... The carburetor adjustments are critical also... as follows:

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S 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 (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note 1: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

Note 2: If the engine should be a three (3) cylinder engine with three (3) carburetors, start the adjustment sequence with the center carburetor.

When you have finished the above adjustment, 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.
 
Sorry Johnnygjr I misunderstood you earlier. I thought you meant a carb rebuild. I actually didn't decarb it. Also, you want me to adjust the low speed needles with the engine running?!
 
Eldorado said:
Should be fairly accurate to do on muffs right? Or should I do it in a can?
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I've adjusted hundreds on a flushette... BUT... always double-checked the setting once the rig was in the water. The purpose is to have the engine running 98% normal in the water to start with.

The ideal setup would be to have the engine idling in neutral in a large plastic trash can with the water level 4" or 5" above where the lower unit attaches to the long exhaust housing... this creates the normal back pressure the engine encounters when on a rig in the water. Adjusting the carburetors under these circumstances gets the setting pretty well exact.

The only adjustments you need to make pertain to idle (low rpms). High speed is taken care of via fixed jets located horizontally in the bottom center of the float chamber... way in back of the drain screw.
 
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