5.7 Mercruiser Timing Issues

[outboardguy33462]

I have a 25 Wellcraft Nova with 2 Mercruiser 5.7 L engines. Recently ran boat and there was alot of popping so did a tune up plugs advanced curve kit rotor button and distributor cap and then ran boat again one cleared up for a couple minutes and the other didnt stop popping and then the second one starting popping thinking there is a issue with the timing looking for the correct timing for these motors

 

[ziggy]

Re: 5.7 Mercruiser Timing Issues

look in the adults only thread at the very top of the i/o fourm. in there, item #9 you should be able to find the appropriate service manual for your rig. the service manual will have all the info you need to time your engines properly..

 

[littlebookworm]

Re: 5.7 Mercruiser Timing Issues

What year are your engines? The timing is different with different ignition systems, Thunderbolt IV, V. I would also question the quality of the gas in your tank. If both engines are suddenly popping, you need to look to the common denominator. What could be affecting both, fuel or battery? Most likely, fuel. Please check your tank and post more info about your engines. Hy