Re: 86 merc 150 with bogging problems
There is NO RETURN on electrical parts, which is why it is so important to properly test the ignition system before chaning any parts otherr than spark plugs.
Any problem should be attacked by simpple troubleshooting tests.
Begin with a spark test to ensure each plug wire delivers a hot blue arc across a 7/16 inch gap while cranking. Leave the sparkplugs out and ground all the wires except the one being tested to ease strain on the starter and battery and to prevent any errant sparks from ignition fuel fumes. Repeat on each plug wire.
A compression test can also be done while doing the spark test, you want to ensure all cyls have very near the same compression. The actual # isn't as important as all being welll within 10% of each other as the quality of gauge used can vary.
If any one or more plug wires fail to deliver a hot blue 7/16 inch arc then further testing is necessary.
Download the FREE Ignition Troubleshooting Guide from the Support pages of CDIElectronics
Their easy to follow guide will direct you how to test each component of your ignition system to accuratly determine the fault.
You will need a DVA meter or a DVA adaptor for any volt/ohm meter. An adaptor caan be built easily and cheaply following the directions posted here.
http://forums.iboats.com/showthread.php?t=374544
If spark and compression are both confirmed O.K. then you can proceed to the fuel system.
Repost your findings and we can go on from there.