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he compression on each of the cylinders is 150psi each.
New Plugs
Went thru the carbs 3 time already
checked the fuel pump
Bought a spark plug checker and each one is firing okay.
The engine idles fine but when I try to floor it starts bogging like running out of gas.
Adjusted the carb needles in and out several times
I swapped tanks and filtered the gas to see if there was any junk clogging the intake.
Checked all of the hoses for collapsing but seen none.
Replaced the fuel line from the tank to the engine with a new hose and bulb.

So right now I am out of ideas to try on the engine. It will only tack out at 2300rpm and it should easily hit 6000rpm.

I took it to a marine shop and they could not find anything wrong with it either. The guy told me it was wore out..then I asked him how come the compression was 150psi per cylinder...don't make no sense to me.
So anyone of you old mechanics know anything about these tower of power units and got a suggestion let me know please as I wanted to get my boat to the boat show this summer with the gang.

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Dreams are free, Reality cost money.

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Dreams are free, Reality cost money.

youve probably already checked but are you sure you timeing is advanceing as soon as your carbs start to open?

Necrothread!

Didn't see it until now

First, be sure the butterflies are actually opening all the way up. The 1150's in the early-mid '80's have a plastic cam to couple the carbs to the throttle and timing arm. The follower should be on the outside of the cam, not running in the grove. It will still function in the groove, but will never open the butterflies past about 1/3rd.

When you open the throttle, about the time it begins to bog, will a quick pop on the choke cause a deeper bog, or a surge in power?

Sounds like a lean run, typically slobbering rich will slowly climb through the midrange and lean out. Which engine? assuming that old merc I-6 - What year is it? The little spring on the top of those floats is prone to popping up, and sticking, when it does sometimes it won't close the needle. What do the plugs look like right after a bit of WOT running?

Pump a bit of fuel into something clear, look for milky/watery/separation.

In the ign dept, make sure the flywheel isn't shedding the magnets. Some idiot at merc decided epoxy was a good way to attach the magnets to the flywheel. If they slip it can drop the timing a bunch late

Is the starter pinion disengaging when the engine starts? dragging starter will hold it down.

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Some plan to stroll through Saint Peter's Gates, I plan to go through them at 150mph... backwards... in a screaming ball of flame, with a glimmer belt wrapped around my head, and a NOx button in my hand.

Had the same symptoms on a Mercruiser. The water separating fuel filter was clogged, enough fuel would flow to idle and fill the carb bowls at idle, but would quickly run out of fuel in the carb bowls when trying to plane.

Make sure there are no obstructions in the fuel lines or any clogged filters.

Scott

Fuel lines,fuel lines fuel lines!!! We ,out here in AZ are having problems with lines that are as young as 4 years! Its the stuff we should be drinking( ) that the GOv. is putting in the fuel!!!!

Does it have a diaphragm fuel pump? pin hole in diaphragm will show those symptons..as well as fuel cap blocked vent hole, or a failing coil....Is it a constant miss or intermittent miss when it bogs down....90% of time if it is a constant miss it is fuel/carby...if intermittent it is electrical..hope you find it.

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The Bitterness of Poor Quality, Remains Long After The Sweetness of Cut Price is Forgotten...Thanks Dad R.I.P.

It was the CDI, Capacitor Discharge Ignition, I had my friend next door talk to a Old Merc mechanic and he said more than likely that was it. $250 for that but it made the engine run good.
Jimmy

_________________
Dreams are free, Reality cost money.

Good one Jimmy...it is hard to diagnose when you can't hear it running...Glad you got it fixed.

_________________
The Bitterness of Poor Quality, Remains Long After The Sweetness of Cut Price is Forgotten...Thanks Dad R.I.P.

CDI would do it. Usually they just knock out 3 of the 6, or are 100% no spark.


Failing under load happens, really rare. Not a good day for a lottery ticket, it's bad-luck week.

_________________
Some plan to stroll through Saint Peter's Gates, I plan to go through them at 150mph... backwards... in a screaming ball of flame, with a glimmer belt wrapped around my head, and a NOx button in my hand.