2002 mercury 250 xxl

by Patrick
(Lebanon Indiana)

I was having minor starting ,running problems. figured it was due for a tune. marina changed water filters and put in new set of oem ngk br8hs sparkplugs. first trip out boat started and ran great but after a couple hours on water started to start hard and did not want to run very good. would die at idle loss of power. they had scanned motor, 135 compression all cylinders no codes. called marina this week, they went back scanned motor,no codes,but new plugs were fouled. changed plugs again but put in champion 941 plugs. charged both times $580 and change twice. boats on lake michigan,inside storage. have a problem with them changing plugs twice without trying to find why. had been 4 years since plugs had been replaced. live 2 hours away from boat have been back on it. also have problem with them using champion plugs second time. have not called the yet,trying to get some helpful thoughts. Thanks Patrick