1994 Merc 150 fuel problem?

Newer power head (rebuilt 7 months ago). Been running good until the past few weeks. Idling is great sometimes and sometimes it's not. The past 2 times out if I'm at half or above on the throttle it will cut out. Bulb will not stay hard. It's on a center console with built in tank. I'm thinking air leak somewhere or could it possibly be electrical? Any help is appreciated.

brich626 said:

Newer power head (rebuilt 7 months ago). Been running good until the past few weeks. Idling is great sometimes and sometimes it's not. The past 2 times out if I'm at half or above on the throttle it will cut out. Bulb will not stay hard. It's on a center console with built in tank. I'm thinking air leak somewhere or could it possibly be electrical? Any help is appreciated.

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I have already replaced fuel pickup in tank and wonder if I should keep pursuing fuel problem or start diagnosing electrical?

first two checks on the problem is compression and spark...spark needs to jump 7.16 inch with a good snap...then you decision is it a fuel or fire problem...the bulb should get hard when you pump it up but will not stay hard when running..this is normal...i would use and inductive timing light to see if it is a fire failure..take the cowl off and run it with the timing light where you can see it..on most lights you will have to tape the trigger back...then when it fails move the light from plug wire to plug wire to check them all...
if it looks like a fuel problem you may pump the bulb to see if it helps the problem....but dont expect that bulb to stay hard if you are running without pumping it....