Knock in engine bay after recon heads

[holden 3.8]

reco heads on vt 2000 holden now has knock in the engine bay only when u start up when warmed up it seems to go away, noise was not there before i did the head gasket have any ideas to ressolve my problem thanks holden 3.8

[GMMAD]

lazy lifter I would say

[oztech007]

Yeah sounds like one of your valve lifters are a bit bodgy. You could try putting 1/2 a litre of Diesel Fuel (Mechanics Trick) in your oil and go for a 10 Min drive. Rev the %$&$ out of the engine. Sometimes this free's up the lifters. (This works better than any lifter treatment and is perfectly safe).
Make sure that you then Do an oil change/filter after this procedure, as you dont want to be driving around with Diesel in your oil for too long.
Use a 10W/30 or 10W/40 Oil as well.

[vxcalais_01]

Dont put diesel or any solvents into the car. Only one i would try is Nulon Lifter free. otherwise run a diesel oil instead or non solvent cleaner like Auto-Rx etc....by the way, did you change the lifters when you changed your heads ? They shouldnt have been gummed up already. Problem with sudden solvent/diesel flush is the damage it can make to the seals of the car and dislodge something all of a sudden. Dislodging gunk from a seal is only asking for trouble.

[vxcalais_01]

http://www.widman.biz/uploads/Corvair_oil.pdf

Conincidently, i started reading this later after i posted, read it all, about oil , noise, etc why not to flush etc, purely fantastic article.

If you too lazy to read it all, read Page 5 and page 17 points 11 & 12. Will answer it all for you.

P.S on viscosity, 5W30 are the norm due to lower temps and extreme variations throughout a day. 10W40 and 15W40 would be our equivalent of 20W50/25W50. Australia has higher ambient temps than U.S and we keep our cars for longer.