I have a 1994 Mercury XRI

Went out this weekend and ran about 15 miles to the first fishing hole. Motor ran good everthing was fine. After fishing for about thirty minutes I started back up and ran for about a mile when I heard a Rattling or a Kind of a Tat-tat-tat sound. Needless to say I run it slow back in. There are a couple of things that I would like to narrow it down to if I can before i take it to the shop. Last time I had it out I hit a stump but was a idle speed when I hit it and when i got it back two of the low water intakes had wood particles in it so i cleaned them out. There was no water pressure drop or alarms that day or on the weekend trip. And on this weekend I had no water pressure or oil problems and no alarms. One thing that I did do before we went this weekend is fill the gas tank. Also the rattling would not do it at lower rpms or if it was in nuetral and i reved the motor. Also when I got home I pulled all the plugs they all looked like they were getting fire no water droplets or anything and no metal sticking to them. One thing that I did notice was that my motor would shake back and forth about a 1/4 to half inch. It is not loose at the jackplate or transom mount but the motor will shake the only thing that shakes is the motor itself. Any help is appreciated.

Thanks,

Travis

A little more info would help, what brand of motor , horsepower age, type of boat etc.

Sorry , missed the brand. With the boat out of the water and  the motor off and key off put the motor in gear and see if there is a lot of play  in the prop shaft by twisting it back and forth. Then put the shift in nuetral and spin the prop with your hand and see if you notice any woble.

Change the foot oil and look for metal shavings or chips in the oil or sticking to the plug.  I am suspicious of the gears being damaged when you hit the stump.  Stainless steel prop?