mercruiser 140 no start

reaper2911

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I have a mercruiser 140 has spark to all 4 cylinders compression is 125 across the board carb just redone still no start also 10 degrees before tdc I am out of ideas any from community?
 

alldodge

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Bad gas or water in the gas

Is it a new to you boat, and if so how long have you had it?
If the throttle is pumped, does any gas squirt down the throat of the carb?
 

reaper2911

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Gas is new 89 with seafoam there isn't anything moving through jets but there is flame I can see through carb it is new to me tore down and changed all gaskets only things not new is carb and piston rings and rod bearings
 

alldodge

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With nothing moving thru jets its the carb unless the fuel pump is not working
 

reaper2911

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The carb was replaced did another bench on compression and found cylinder 4 is now at 100psi and oil test says piston rings is there any sub for rod bearings since because of covid my marine stores cannot order them? It did try to start with new carb thank you for that also
 
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alldodge

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There is no such thing as marine bearings, same with rings. Once the machine work is done, then you will know what bearings are needed and they can be ordered from where ever

Yes, 100 will run but not very well
 

alldodge

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I'm seeing fuel squirt so must not have spark.
The 140 should have points

Remove the distributor cap, loosen the distributor so you can see the points. Rotate the dizzy watching to see if the points open and close. If they do, turn ignition ON and rotate the dizzy again to see if each time the points open/close there is a spark between the points

If you get spark at the points, notice which plug wire the rotor is pointing to. Remove the plug and wire and place the plug grounded to the block. Install dizzy cap and have plug wire attached to the plug. Rotate the dizzy back n forth as before to see if you can see the plug spark
 

reaper2911

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so I have spark also flame coming from under carb also all point are firing all cylinders
 

Scott Danforth

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What is the dwell per a dwell meter?
 

alldodge

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Spark on all cylinders, even flame under the carb, new gas and it does nothing in the way of starting

I have nothing, sorry
 

Karl1432

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Get a can of starter fluid. Squirt some into the carb. If it fires then the issue is a fuel issue. If not still at fuel or spark (at the right time).
 
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