not getting fuel into cylinders

T

towerclimber

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I have a 86 4cyc. Mercruser that i had running all last year after having new head put on it. 3 weeks ago we started it up and ran for 30 min. Then it just quit. It will turn over i have compression good spark and I'm getting fuel into the Intake. Here's the best part. I'm not getting fuel into the cylinders. I cleaned all the plus and tried to start it with starter fluid and gas then pulled the plugs they are dry as could be. What could it be stopping the fuel from getting into the cylinder?
 
Don S

Don S

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Re: not getting fuel into cylinders

Vacuum is what pulls the fuel into the cylinders. If you have a vacuum leak in the intake or carb mounting that will prevent it.

You say you have spark, but do you have it to each spark plug? A bad cap or rotor will prevent spark from going to each plug, but you would still have spark coming out of the coil.

And Thanks for starting your own thread.
 
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towerclimber

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Re: not getting fuel into cylinders

Yes I'm getting spark on all 4 plus. If i have good compression wouldn't i have good vacuum? I pulled the valve cover and all valves are working.
 
Don S

Don S

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Re: not getting fuel into cylinders

towerclimber said:
Yes I'm getting spark on all 4 plus. If i have good compression wouldn't i have good vacuum? I pulled the valve cover and all valves are working.
Click to expand...

Not if you have a huge leak on the intake side.-
 
T

towerclimber

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Re: not getting fuel into cylinders

So if i do the old school trick with starting fluid and spray it around the intake gasket it should tell me right?
 
T

towerclimber

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Re: not getting fuel into cylinders

Don, thanks for all your help. I'll try the trick tomorrow and let you know.
 
NHGuy

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Re: not getting fuel into cylinders

Starting fluid will tell you more if the motor is running. If you still can't get it to run you might try spraying some soapy solution around the gasket. open the throttle, shoot some compressed air down the carb & then watch for bubbles.
 
T

towerclimber

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Re: not getting fuel into cylinders

Update,
I drained all the fuel that had water in it cleaned out the carburetor changed the ignition coil. it wants to start but it won't. do you think the timing may be out? what should the timing be?
 
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