Recent content by Guffer

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    Mercruiser 120 poor starting

    Many thanks for coming back to me so quickly. Will replace the fuel pump and condenser. I had wrongly assumed as fuel was getting to the carb that the fuel pump was working. I have now pulled it apart and can see crazing on the diaphragm which could have easily caused a small leak. The 2.5...
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    Mercruiser 120 poor starting

    That’s kind ESGWheel! I missed your post and had started calling marine engineers but it may be weeks until they can help :-) Did some more Googling a saw a post re a car engine that was flooding the oil with fuel. Sure enough when I emptied the oil it was full of petrol….so now I have something...
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    Mercruiser 120 poor starting

    I can only guess that the spark is not strong enough or water is getting in to stop ignition happening.
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    Mercruiser 120 poor starting

    Yes, but maybe a bit weak. One thing that I forgot to mention is i replaced an earthing wire which had degraded. It ran from the fixing point in photo to the fuel sender on the metal fuel tank.
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    Mercruiser 120 poor starting

    So, this is becoming a proper 2 pipe mystery. Had hoped to be back to the salty stuff a month ago but my MCM 120 still won’t start so am stuck on the river! This where I am up to: Compression Before winter the engine was running fine but cylinder 4 was low on compression Had the head reworked...
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    Mercruiser 120 poor starting

    I've learnt a lot in a few months. Thanks v much.
  7. G

    Mercruiser 120 poor starting

    Very helpful! Wish my spark look like that :-)
  8. G

    Mercruiser 120 poor starting

    Just cleaned and gapped them. Will put a meter on them this weekend.
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    Mercruiser 120 poor starting

    Thanks. I cleaned the points and gapped them but think it was more than .016. Will file, re gap and set dwell. Thought timing should be 8BTDC?
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    Mercruiser 120 poor starting

    Not making much progress :-( I have relooked at the carb and adjusted slightly but nothing major. Ive used an in line spark tester and there is some spark from center of coil but it doesn’t look that strong. I tried new cap and rotor, different battery but no luck. Not quite sure what to...
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    Mercruiser 120 poor starting

    Thanks very much. Really appreciate the help. Spark wasn’t coming though to the plugs. I will relook at cap and rotor to see if there is anything obviously wrong. Wires are new. I have cleaned and gapped the points, is there anything else that might need cleaning under distributors cap? Will get...
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    Mercruiser 120 poor starting

    Re plugs. These are new and I’ve gapped them. I put a new cap on. Is it possible put this on the wrong way (I took screws out before realising they are different sizes.) Does it matter? The rotor looks in good health. The one that came with the new Quicksilver distributor cap seems too tight to...
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    Mercruiser 120 poor starting

    Thanks for all the help. Much appreciated. Have checked the filter a few times and it’s fine. The needle moves freely but I will re look at this again and check it moves when air is blown in. Re the float adjustment. No i put it back as it was….partly this was because I didn’t find my carb...
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    Mercruiser 120 poor starting

    Ignition on, there should be 12v at the coil pos. YES Coil neg will be either 12v or 8ish depending on whether the points are open or closed. YES 12v Disconnect all wires except the points from the neg side. DONE To check the coil you can repeatedly ground a jumper from the neg side and should...
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    Mercruiser 120 poor starting

    This is what i found when I took the top part of the carb off. Is it normal for fuel to sit like that?
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