newbe I have a 92 502 mag mk 4.It had low compression so i did the test and showed it was more than likely in the valves.I pulled the heads and found bad lobe on cam.want to get back on water asap and have another engine i will be putting to gather next year.Was looking for ideas on a good flat tappet cam kit to put back in

I would post this in the Tech Section. My observation is that lots of people will give you good advice there. If you hjave a stock engine there are people that know what to use. Flat Tappet is old skool. Would recommend a roller but requires new lifters. Remember, you have metal in the oil if you wiped out a lobe.
good luck.

Wannabe

cantact Bob Madara with your thoughts and he will hook you up. costs a couple bucks over an off the shelf part but worth it.


Contact | Marine Kinetics - Marine Engine Shop

THANK YOU WANNABE, and GLASS DAVE for responding. Newbie here and want to make sure that I get my questions posted into the correct area so I can get the answers I need. I figured out how to get my posting into the TECH area, so am going to do that right now- ANY HELP anyone gives is much appreciated! Have a great day - Dave

I have a new take out roller cam and springs out of a 502 crate motor, stock it made 450 HP and 550 torque.. you would need to get some roller lifters and new push rods, though. The whole engine needs to be torn down and cleaned due to the metal in it from the worn came lobe..

what do you need to do to the block to run a roller? There is no girdle boss to hold the lifters down. The motor has good oil pressure. There was one lifter that was a little rough on the edge so looking at the cam, I could see that it didn't have the height of the other ones. I don't think this just happened because ever since I put the motor in the boat (it's been 4 years now), it's never run as fast as you'd think it would for a big motor and a smaller boat. So, beginning of last year, I did a compression test, and it was low compression on a few cylinders. But I just ran it anyways, to finish out my boating season. I have another motor but I'm going to rebuild THAT one for next year so I was just hoping to put a cam in it and redo the heads on it for THIS year so I can get out and enjoy the season that's already started. Would the damage already be done if there was metal in the oil? I changed the oil meticulously and every year before storing it....So hoping it can be put together to get a season out of it. I appreciate all your time and advice. THANKS Dave