Topic: Cam and Rocker Damage 22R PU

[Yomota]

Hi I'm from Eastern Washington.  Any way about 2000 miles ago I did a complete overhaul on a 22 R, replacing the rocker arms and cam as part of the over all package.  The other day the thing got real noisy and I pulled open the valve cover to discover the #4 intake cam and rocker were damaged.  These are after market parts and it looks like the rocker actually wore through and then cracked away.  Anyone who has experienced this know what exactly is the cause of this?  How do I avoid similar problem in the repair? 

[jimbo74]

intake cam? or valve? if its the valve, sounds lie kit was too loose or way overtightened

[Yomota [OP]]

My post says, "The other day the thing got real noisy and I pulled open the valve cover to discover the #4 intake [emphasis]cam and rocker were damaged."  Intake cam and rocker - not the valve and not the exhaust side.  I've adjust the valves on this 1985 for over 20 years (original owner) -they were not over tightened or loose when I did the overhaul and did a recheck after break in.  Anyone who has experienced this know what exactly is the cause of this?

[79coyotefrg]

ive had this happen to me befor,  get some TOYOTA  valve adjusters,   with mine the screw adjuster  came apart and destoyed the rocker,  luckily my cam was ok,  i have 3 or 4 stock cames in my shop if ya need one

[Yomota [OP]]

Thanks 79Coyotefrg.  Mine failed at on the rocker pad area and messed up the cam lobe.  I've heard of the adjuster failure area too and I think your advice to use OEM ONLY is very sound.  I talked to engnbldr and he told me he sees cam failures from time to time, often when new aftermarket rocker arms are installed.  For that reason he will buy used ones from a wrecking yard and refaces them (I don't recommend) or replace with newToyota arms only (about $25/rocker).  I also talked to LCEngineering and they told me they only sell OEM rockers directly from TOY and they twice harden the cams they sell.  LCEngineering told me the Chinese aftermarkets are problematic - something to do with the hardness of the casting and cam.  They said they have tested many rocker aftermarkets claiming to be as good as OEM (TOYOTA) but they fail.   I think my problem wll be solved since I ordered a complete new rocker assembly and street cam from LCEngineering but it was over $500 (gulp!).  New shafts new springs, new..new..new...LC gave me good tech advice as well.  They gave some excellent advise on replacing the cam without distubing the head and breaking the seal.  Later I also found an article by Josh Carlson at:
http://www.4x4wire.com/toyota/tech/camshaft/
that was consistent with what LC told me on doing the job without messing with the head gasket, intake and exhaust.  I now have the double timing chain conversion kit on this engine so there are some tricks/advice provided by LC for putting the cam gear back on.  Anyway I was wondering if anyone else here experienced this sad story of destroyed rockers and/cam since I used after markets.

[79coyotefrg]

im running the LCengineering stageII  race cam,  very nice,  almost 50,000 on that cam  and no signs of wear   so yea they are good stuff