Hi every one i would love anyones thoughts on tappet clearances on my rb30 i have standard lifters which have a rattle. they are not tapping as if it has a noisy lifter they seem loose. well i removed the rocker cover and checked the clearnace between the lifter and the rocker arm and it has about 5 thou clearance..In theory it shouldnt have any but my motor has. I repalced the lifters with new ones it seems a little quiter but still not as quiet as it should be . has any one seen this before it has a regrind cam in it .. now i am thinking that the cam shop has taken too much off the bottom of the cam hence the excessive clearnace. how do i get the clearance out . my thought are either a new cam (which i dont really want to do) or machine the rocker posts 5 thou has any one done this before any thoughts would be appreciated thanks John

whats the oil pressure when running?

Has it got a re ground cam? If so its coz the lifter plates need to be matched to the cam to take up the slack

You'd like to think the machine shop would have asked for the lifter cradles or head to check.... surely .....

the machine shop had the complete head. i gave them everything. i got the head back complete. you cant check the clearance unless it has oil in the lifter ,there is enough oil pressure. would anyone know who to talk to in sydney anout this. the cam is reground what do i need to do

As boosted_wagon has said if it has had a cam regrind you need to machine the lifter blocks. Phone whoever did the cam and they should be able to tell you how much. The ones I've done have been between 20-50thou.

ok thanks everyone so you machine the lifter block so the rocker sits lower , i will call the cam guy on monday and see what he says to see how far i need to machine thanks

are you able to order oversize lifters?

I have no idea i have never heard of them over size as in longer one???????????

yes. I thought they were available for the ole trusty 308's years ago but then again I may have been thinking of the push rods lengths.

hey guys has anyone have any idea how much i need to machine off the lifter blocks. does it depend on the grind of the cam or should i goo off my measurements and just take out the slack and 5 thou more????????????

the reason u need machined lifter plates for is due to the cam being machined (diamiter reduced) so with this u need to bring the lifters and the rocker arms closer to the cam to keep the everything in sync....most cam places take off between 20-55tho depending on how agressive the profile is u are having done.......

Thanks Boosted I really appreciate the advise. i suppose you cant really take too much off as the lifter will take up the slack if you know what i mean. I might take them off and egt the machine shop to machine 30 thou off them.

Mate speak to the place that did ya cam and find out how much they took off the cam... It usually says on ya cam card... What brand of cam is it

i spoke with the cam place and je says they normally take off about 30 thou, i took the lifter blocks to the machine shop today i should them back tomorrow ill throw them back in and try it and keep you posted once again thanks for all your help

ok so we shaved 30 thou of the bottom of the lifer blocks and put them back onto the head and all is ok the engine sounds normal and seems to run better and smoother thanks everyone for your help