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1988 Johnson 48 SPL Fuel problem

With all the fore mentioned information and diagnostics, I pose a new question. Could the reed valves be BAD??? We tried different jets last night (many many thanks to t2stroke for providing the jets), with no luck. Was running considerably worse. I did notice, what I thought was a lot of fuel inside the intake housing (blowback?). If the crankcase can't "precompress" the fuel and air mixture, then it wouldn't be able to get the proper amount into the combustion chamber. Correct?
 
That is correct.-----And the reed valves rarely go bad.----This motor was apart before I believe.----Did you check / inspect the labarynth seal between upper and lower cylinders ?
 
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Well I tripped up on something while looking for other information the other nite. Your 45 cu in motor shows up under a 1996 28hp listed as a 40JR. That's jet. They were short shaft motors for the reason you found out. The unit has to be even with the bottom of the boat to perform properly.
Now the reason this is important (in my mind anyway) is a 40 has a very small venturi & would normally take a small HS jet. This jet takes a 49D stock. Your 48 has considerably larger venturi carbs. The only problems I'm having with this is you saying the running is getting worse as you go bigger on jets? Blocking off air or priming tells us it is lean, but putting in a larger jet is not helping? Now you have to wonder about fuel supply, float setting, but these motors are not known for large fuel consumption.
I am at a lose. Maybe I have said something that will get someone else thinking? What are you thinking?
Reeds just don't give problems on this motor.
 
The motor was originally mounted to low. We raised it 1" using the existing holes in the mount. It's still about 3/8" low. I plan on fabricating a new aluminum riser mount for it so we'll be able to position exact. I'm going to test fuel pressure, and possible a leakdown. Not looking forward to pulling the powerhead again but that might wait until the season is done. Probably going to set everything back to where it was running good and let the son use it, while I do some more research. Reeds are easy enough to pull and re inspect. There were a couple petals that had the tiniest of gaps, but didn't seem awfully out of whack.
 
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