JFROG

have 91 RS with 305 tbi. notice a tapping sound from engine when temp is at operating temp(about 170-220) oil is not low and oil pressure looks normal. does the usual 60 when cold and 20-50 when at operating temp. fluctuates with rpms ( noted this on several third gens) thinking about trying marvel mystery oil or running a quart of atf in the oil to see if that helps. any other opinions appreciated

xpndbl3

iTrader: (5)

is the tapping sound coming from the TBI throttle body, i know on my truck the TBI injectors make some noise.

JFROG

seems to be on the passenger side. not sure to tell exactly where without an auto stethoscope

xpndbl3

iTrader: (5)

tapping sound could be exhaust leak at the passenger head, loose rocker arms nuts, etc etc. it sounds like the motor is making good oil pressure so i wouldn't sweat it being a bearing noise just yet.

JFROG

will check gasket on headers if ok will check torqe specs on rockers. see how that goes, thanks

JFROG

will check gasket on headers if ok will check torqe specs on rockers. see how that goes, thanks

jamon8

iTrader: (3)

transmission fluid- please I have to hear this one

JFROG

put in new exhaust gaskets on headers and ypipes. sounded no different. so then i removed the valve cover and tightened the rocker nuts about half a turn, i couldn't find the specs to torque them to so i didn't want to put them to tight. now tapping has gone down to a light clicking. how tight are the rocker bolts supposed to be? should the rocker be able to move at all?

jamon8

iTrader: (3)

there is a tightening sequence not a specific torque spec. some else may type the whole procedure but I will tell you to get the helms manual. chilton and haynes will have some of the same info but they are like buying a v-6 f-body and helms is the firehawk

Dialed_In

iTrader: (3)

you probably made it worse by turing the nuts Google up "adjusting valves SBC hydraulic roller"

jamon8

iTrader: (3)

do yourself a favor and put new rocker nuts on when you go to adjust them again.