the moters are 610 cub. THe lifter on #7 intake was wipped out and got the cam too. any ideals on why it failed big lumpy cam 9.5 comp .the cam #139546 94B2. and they are 720 hp.#2 cyl. also has avalve issue the comp was down to 100 psi highist reading was 180 about 500 hrs on the moters.any ideals .roller lifters and roller rockers .mec.

500 hours on that monster and your complaining about a bad lifter? We all wish we had your problems!
Dennis Moore

change mine every year to be safe

Wow 500 hours, I would be overjoyed with 500 hours on a motor like that. It's time to start over.

YEAH..............

you needed new valve springs and lifters about 350 hrs ago

I would have to agree with the others. Your problems are LIGHT with an engine that size and amount of time! Time for a REBUILD/FRESHEN UP!!!

One hard season is about all that can be expected out of that kind of power. Tear the other motor down too.