Recent content by AusFox

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    350 MAG MPI Head Bolt spec

    Hi all, Has anyone got the 350 MAG MPI head bolt sequence and tensions?
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    Mercruiser 350 MAG MPI

    UPDATE - Time to pull the heads off Well it seems the more I find damaged or out of spec and rectify it leads us to another issue!! After performing another leak down test the results are not great! The intake valves on the cylinders (1,2,3&4) are not seating well enough, I believe this is...
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    Mercruiser 350 MAG MPI

    Hi all, I got down to the boat on the weekend! The oil has been changed and the TPS reads 0.63V in neutral and smoothly increase to 4.49V at WOT. I have ordered a replacement MAP sensor but that is yet to arrive, hoping that will be the final fix to this issue as the engine is performing above...
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    Mercruiser 350 MAG MPI

    Hi Lpgc, Thanks for the detail!! When the engine locked up it was certainly fuel. When I take the MAP sensor out and the engine starts straight away I agree the reason it starts is because the extra air it's able to suck in through the hole. I will look into the IAC operation and also the TPS...
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    Mercruiser 350 MAG MPI

    When I was cranking and trying to use throttle it wouldn't start. Apparently before I got involved the only way they could get it to start after sitting hot was to work the throttle and it would start and rev up. I agree by removing the Intake manifold sensor it sucked hard through that hole and...
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    Mercruiser 350 MAG MPI

    Yes mate that is the sensor I have and removed.
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    Mercruiser 350 MAG MPI

    UPDATE So I have now done everything I can think of without the use of the scan tool as I still can't get hold of one! I used my PICO Scope to monitor the crank and cam sensors, and they seem to be working correctly with each other. Water test the boat and its running very well now with alot of...
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    Mercruiser 350 MAG MPI

    Thanks, I have found the crank position sensors brass threaded insert to be a bit loose so I have removed that and going to put some retaining compound on it so that I can eliminate the possibility the crank sensor is vibrating. I am trying to find a new crank sensor here locally from a GM to...
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    Mercruiser 350 MAG MPI

    What sprk plug's do you guys all reccomend for a 350 MAG Bravo 3? Currently running a NGK TR55IX (This is what was previously fitted). See attached the specs on this plug
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    Mercruiser 350 MAG MPI

    Thanks alldoge, The boat is an 80's caribbean and I understand the engine components to all be from around the 2008 time frame. I will do the comps tonight and also look at the Diacom and report back what I see. On the hose it all sounds great and is smooth but when we water test we get the...
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    Mercruiser 350 MAG MPI

    Hi guys, I have not been able to locate a serial number yet as I the engine has previously had the block and head's replaced and all the electronics from the old engine got put onto the new engine. All fuel filters have been replaced, lines all cleaned but will be doing that again when I...
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    Mercruiser 350 MAG MPI

    I have replaced the cap and rotor, when cylinder 1 is at TDC the tang is on the number 8 on the dissy housing and I believe that is the proper location. With a timing light on it at idle it shows the mark on the harmonic balancer to be firing around the indicator groove. Spark Plugs have all...
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    Mercruiser 350 MAG MPI

    Well my battle continues!! After sending the injectors away for a test and service and telling them that if they have any doubts about them just replace them, I have found 1 of the injectors is stuck open, this has now been replaced. I have a full set on order just to be sure now!! However...
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    Mercruiser 350 MAG MPI

    Thanks for your help so far! We are in Australia and don't have anyone we can hire a scan tool off that will work with Mercruiser!! I have 3 other high end scan tools such as G-Scan, Jaltest and Autel but none are able to work with this engine. I hope to have the serial number later today but...
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    Mercruiser 350 MAG MPI

    Gday to all the brains trusts here, I have been assisting with a mates Mercury 350 MAG MPI that has had some running and hot starting issues. The engine would run ok but after running for an hour or two if we shut it down to fish then tried to re start it 30 mins later the only way we could...
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