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1976 120 omc jet settings

So ok here's more of the problem I had before buddy played with the jets, the Boat starts good I go to take off push the throttle right down and it's only doing 47km/h and that was tested with the iPhone app, the every electronic on the engine has bib replaced with new same with new oil I have bin running two weeks since oil change and it's still golden not black or milky rpm stays right at 2k there's no bak firing going on nothing but yet I put jb reverse it winds out good rpms go up even when it's out of water when hooked too the garden hose it'll wind out like it should intil it's under load then it does it prop has bin changes to new 15x16 which the boats a 16 foot grew 154 I just dont under stand could it be related too the carb also the tinning was set properly I just don't know where too start too sync this problem
 
Also put new plugs in and did a reading after twenty mins of full throttle electrodes are white but around them on the metal part there's black carbon and on the finger creating the gap
 
Also put new plugs in and did a reading after twenty mins of full throttle electrodes are white but around them on the metal part there's black carbon and on the finger creating the gap
 
Jason_2012 said:
So ok here's more of the problem I had before buddy played with the jets, the Boat starts good I go to take off push the throttle right down and it's only doing 47km/h and that was tested with the iPhone app, the every electronic on the engine has bib replaced with new same with new oil I have bin running two weeks since oil change and it's still golden not black or milky rpm stays right at 2k there's no bak firing going on nothing but yet I put jb reverse it winds out good rpms go up even when it's out of water when hooked too the garden hose it'll wind out like it should intil it's under load then it does it prop has bin changes to new 15x16 which the boats a 16 foot grew 154 I just dont under stand could it be related too the carb also the tinning was set properly I just don't know where too start too sync this problem
Click to expand...
This is what I'm talking about
 
Flame arrester nice and clean? no exhaust leaks or other reasons engine not getting lots of clean air? Watch the linkages and make sure throttle is opening all the way, choke is opening up... all those sorts of visual checks.
Then compression test the engine.

then I would check the timing advance weights and springs under the points plate in the distributor. They like to rust up and get gummed with 30 year old grease and then no advance = no power at higher rpms.

If that doesn't fix things, I'd move on to checking fuel pressure at the inlet to the carb.
 
done all compressions 130 on all four. distributor is brand new including the stem. im kinda think its fuel pump. as sometimes when ran bone dry its not priming the greatest but i see another glass bowl under pump has tag in it that says if fuel flows into here pump needs replacing
 
yeah i realized that tonight. could a new throttle cable cause this im stumped put sea foam in crankcase and in fuel but 49kmh on iphone app just doesnt cut it for me
 
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