Stumped…AGAIN, 1962 OMC 10hp

[beerman57]

Recirculation line is good, "if" it’s the top seal, losing that much fuel, wouldn’t it have quit running by now / quit running so good? Won’t take long to pull the flywheel, I planned on finishing the break-in today. "If" it’s the split in the block valves, wouldn’t I be seeing the red gel-seal being washed out?

[fleetwin]

Great point about the recirc hose, that is right in line with the shift handle….Hope it is something simple like that….A leak in the lower fitting/hose would be hard to see, even with the flashlight. You can simply remove the flywheel inspection plate to have a look at the mag plate to confirm/rule out upper seal issues….
A minute leak in the crankcase halves would affect idle much, but I sure want to be WRONG about that guess….

[optsyeagle]

My bet is on the recirculation hose. My 1961 5.5Hp will have fuel in the pan after I take it out on the lake for a while. Had this for years. Thought it was the packing nuts so cleaned the carb and no change to the leak. If I idled it in a barrel the fuel never showed up. I doubt I idled it for more then 15 minutes but you had to take it out on the lake to notice it when you got back, and it would be there everytime. Tried running it on the lake with the top off to hopefully see where the leak came from. No luck. My guess now is it is my recirculation hose. I have changed it after the end of last year but have not put it in the lake to see if fixed it.

All I can say is that the motor runs perfectly and has run this way for years. The only complaint I have had is this small clean up of fuel when I get back to the dock.

My other thought might be the leaf plate gasket leaking. I would think the motor would run rough with a leak there but I have never had one to know for sure. All I know is it does have a gasket, it has fuel and it has positive and negative pressure to possibly shoot the stuff all around and really make a mess of things.

If you find the problem let us know. I can post my result when I get my motor in the water, but I live in Canada and prefer the water above 50F just in case I fall in the water. I prefer it if I can still move my arms after 10 minutes in the water. It really helps to keep your head above the water line. My guess is my boat will go in within the next 2 weeks.

[dougs-outboards]

Grasping at straws here… Seems to me I read a post about those square fuel pumps leaking fuel into a cylinder somehow. Can’t remember exactly what was said and cannot find the post. Perhaps raw fuel intering somewhere and coming out the shifter shaft? Worn or missing o ring on the shifter? Dunno. It’s a stumper for sure.

Do you have another known fuel pump you can install to check?

I would check the recirc hose first.

[beerman57]

Not the top seal, leaning toward the recirc hose, although no obvious sign of leak, I guess it could be spraying fuel? Change without pulling powerhead? I thought about changing it before final assembly, I have a brass one from a QD17 I think. At this point, pulling the powerhead isn’t the end of the world, better than having to split the block open!! No boat ride for me today.

[fleetwin]

I would simply replace the rubber hose, or at least remove it and cut it back a bit on both ends. I would not try to convert it back to the metal recirc lline on older engines. Once you have repaired/replaced the rubber recirc hose, I would simply pack paper towels in tightly around the bottom of the hose/fitting, then run the engine again. If the problem persists and the bottom of the hose/fitting is soaked, then we will have to look closer at that area….
I am assuming there is wetness inside the motor pan as well, not just outside on the shift lever. This is the engine that you drilled the auxiliary cooling hole for the hot exhaust hsg/shift lever, correct?

[beerman57]

No that was the QD19. Bought this block from Don Kellogg and it seems fine, besides maybe the recirc hose. Looks like pulling the P/H and mag plate are the way to go. Remember, the whole P/H is covered with fuel (recirc hose spraying it out and air movement from the flywheel spreading it around?). BUT, that raw fuel dripping off the lower shift arm seems to be a separate problem to me. The shift arm through the midsection has very, very little slop.

[beerman57]

Well, the new recirculation is on and powerhead bolted back to midsection. I don’t see anything wrong with the old hose, and it wasn’t wet at all with fuel. If that isn’t it, I will be very unhappy. I just don’t see ANYTHING leaking, but whole powerhead is coated with fuel.

[cajuncook1]

Have a peak at your fuel pump. Sometimes the plastic top over the screen will have a fine crack or the plastic top will not apply even pressure over the gasket. Fuel will slowly leak all over. Had that happen to me on a 1976 Evinrude 9.9hp that I bought for $40 bucks. After I cleaned and set the points, cleaned the carburetor, replaced the impeller and replaced the cracked fuel pump top, it ran great.

Don’t get me wrong the guys have given really good ideas, I am not disputing them. I thought I would just throw out another what if.

[beerman57]

I’ve pretty much checked everything, put on a new fuel pump, triple checked bolts and cover. That’s kind of why my post is titled "stumped". If it’s not the recirc hose, I think I’ll just make sure both pistons are even as far as TDC/BDC and let it rot in my garage.

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