my boat has a super charged 502 in it. a couple weeks ago i was out in the boat on a test run with new plugs and wires. everything was going great till i got it a little. was doing about 55 for about 2 minutes when i noticed the temp was getting hot so i let up on the throttle. after a couple minutes it cooled back down. the boat is new to me but the last couple times i took it out it didnt get hot. the oil temp got pretty hot but i slowed down after i say that also. so i wanted to see if it would get hot at a slow cruise so got up on a plane and started cruising about 35 mph at about 2800-3000 rpm. when a all of a sudden heard a knock/rattle for a second then nothing. then about 10 seconds later it happened again so i let up on the throttle and was just in gear at a idle and opened the hatch. about every 5-10 seconds it would make that knock/rattle. so i was limping it back to the boat launch( i was close) and after about 5 minutes the motor was knocking and rattling like crazy...

i got it home put it on the hose and had a buddy come over( another set of ears ) and we started it for a second. all the noise seemed to be coming front starboard side up top. so a couple days ago i pulled the valve cover off and pretty much all the rocker arms are loose... it has roller tipped rockers..fyi.. my question is how can so many come loose at the same time. i can see a lifter collapsing or cam lobe going flat but pretty much the hole side at the same time???? seems weird. any opinions on what may have happened? something i can check. dont want to buy new cam and lifters if i dont need to.

boat is a 1988 242 formula.
motor is a supercharged 502 96 and newer gen 6 i think it is.

Get rid of those rockers.Nothing but trouble.They gall between rocker arm and ball. They have been doing this for 20-30yrs or more ? Amazes me they still sell them and no one throws them at them. Any turned blue near the base ?

I can't answer if you have other issues (like if cam going flat if MarkIV/GenV flat tappet - you'd have tocheck) but those rockers are issues.

Buyer beware

You said the oil temp was going up ? That typically indicates bearing problems How about oil pressure ? Was it falling ?

I think the first thing I would do before running the engine another second would be to pull the oil filter off and take it to a decent machine shop or engine builder that can cut it open and see how much metal is in it if any. That will tell you your next step.

Where are you located ?

He said roller tipped rockers. I believe he is referring to this type https://www.summitracing.com/parts/sum-141709pl

there not those. they are think walled aluminum rockers. wont let post a link or image.

2 more posts and you'll be able to post pics

Please post better part descriptions then. It will help you and us,Thanks.

we shouldn't have to pull teeth to help someone.

So,,,new slate. Tell us exactly what you have for an engine build and what is bolted to it ,who did programming if Efi, etc,etc and any half way recent maintenance info like impeller replacement and etc.